3928 lines
101 KiB
C
Executable File
3928 lines
101 KiB
C
Executable File
/*
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* fs/cifs/file.c
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*
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* vfs operations that deal with files
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*
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* Copyright (C) International Business Machines Corp., 2002,2010
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* Author(s): Steve French (sfrench@us.ibm.com)
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* Jeremy Allison (jra@samba.org)
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*
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* This library is free software; you can redistribute it and/or modify
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* it under the terms of the GNU Lesser General Public License as published
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* by the Free Software Foundation; either version 2.1 of the License, or
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* (at your option) any later version.
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*
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* This library is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
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* the GNU Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public License
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* along with this library; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
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#include <linux/fs.h>
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#include <linux/backing-dev.h>
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#include <linux/stat.h>
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#include <linux/fcntl.h>
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#include <linux/pagemap.h>
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#include <linux/pagevec.h>
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#include <linux/writeback.h>
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#include <linux/task_io_accounting_ops.h>
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#include <linux/delay.h>
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#include <linux/mount.h>
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#include <linux/slab.h>
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#include <linux/swap.h>
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#include <asm/div64.h>
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#include "cifsfs.h"
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#include "cifspdu.h"
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#include "cifsglob.h"
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#include "cifsproto.h"
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#include "cifs_unicode.h"
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#include "cifs_debug.h"
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#include "cifs_fs_sb.h"
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#include "fscache.h"
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static inline int cifs_convert_flags(unsigned int flags)
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{
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if ((flags & O_ACCMODE) == O_RDONLY)
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return GENERIC_READ;
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else if ((flags & O_ACCMODE) == O_WRONLY)
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return GENERIC_WRITE;
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else if ((flags & O_ACCMODE) == O_RDWR) {
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/* GENERIC_ALL is too much permission to request
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can cause unnecessary access denied on create */
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/* return GENERIC_ALL; */
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return (GENERIC_READ | GENERIC_WRITE);
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}
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return (READ_CONTROL | FILE_WRITE_ATTRIBUTES | FILE_READ_ATTRIBUTES |
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FILE_WRITE_EA | FILE_APPEND_DATA | FILE_WRITE_DATA |
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FILE_READ_DATA);
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}
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static u32 cifs_posix_convert_flags(unsigned int flags)
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{
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u32 posix_flags = 0;
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if ((flags & O_ACCMODE) == O_RDONLY)
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posix_flags = SMB_O_RDONLY;
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else if ((flags & O_ACCMODE) == O_WRONLY)
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posix_flags = SMB_O_WRONLY;
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else if ((flags & O_ACCMODE) == O_RDWR)
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posix_flags = SMB_O_RDWR;
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if (flags & O_CREAT) {
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posix_flags |= SMB_O_CREAT;
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if (flags & O_EXCL)
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posix_flags |= SMB_O_EXCL;
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} else if (flags & O_EXCL)
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cifs_dbg(FYI, "Application %s pid %d has incorrectly set O_EXCL flag but not O_CREAT on file open. Ignoring O_EXCL\n",
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current->comm, current->tgid);
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if (flags & O_TRUNC)
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posix_flags |= SMB_O_TRUNC;
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/* be safe and imply O_SYNC for O_DSYNC */
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if (flags & O_DSYNC)
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posix_flags |= SMB_O_SYNC;
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if (flags & O_DIRECTORY)
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posix_flags |= SMB_O_DIRECTORY;
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if (flags & O_NOFOLLOW)
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posix_flags |= SMB_O_NOFOLLOW;
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if (flags & O_DIRECT)
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posix_flags |= SMB_O_DIRECT;
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return posix_flags;
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}
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static inline int cifs_get_disposition(unsigned int flags)
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{
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if ((flags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
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return FILE_CREATE;
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else if ((flags & (O_CREAT | O_TRUNC)) == (O_CREAT | O_TRUNC))
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return FILE_OVERWRITE_IF;
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else if ((flags & O_CREAT) == O_CREAT)
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return FILE_OPEN_IF;
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else if ((flags & O_TRUNC) == O_TRUNC)
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return FILE_OVERWRITE;
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else
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return FILE_OPEN;
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}
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int cifs_posix_open(char *full_path, struct inode **pinode,
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struct super_block *sb, int mode, unsigned int f_flags,
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__u32 *poplock, __u16 *pnetfid, unsigned int xid)
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{
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int rc;
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FILE_UNIX_BASIC_INFO *presp_data;
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__u32 posix_flags = 0;
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struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
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struct cifs_fattr fattr;
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struct tcon_link *tlink;
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struct cifs_tcon *tcon;
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cifs_dbg(FYI, "posix open %s\n", full_path);
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presp_data = kzalloc(sizeof(FILE_UNIX_BASIC_INFO), GFP_KERNEL);
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if (presp_data == NULL)
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return -ENOMEM;
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tlink = cifs_sb_tlink(cifs_sb);
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if (IS_ERR(tlink)) {
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rc = PTR_ERR(tlink);
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goto posix_open_ret;
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}
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tcon = tlink_tcon(tlink);
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mode &= ~current_umask();
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posix_flags = cifs_posix_convert_flags(f_flags);
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rc = CIFSPOSIXCreate(xid, tcon, posix_flags, mode, pnetfid, presp_data,
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poplock, full_path, cifs_sb->local_nls,
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cifs_sb->mnt_cifs_flags &
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CIFS_MOUNT_MAP_SPECIAL_CHR);
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cifs_put_tlink(tlink);
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if (rc)
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goto posix_open_ret;
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if (presp_data->Type == cpu_to_le32(-1))
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goto posix_open_ret; /* open ok, caller does qpathinfo */
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if (!pinode)
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goto posix_open_ret; /* caller does not need info */
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cifs_unix_basic_to_fattr(&fattr, presp_data, cifs_sb);
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/* get new inode and set it up */
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if (*pinode == NULL) {
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cifs_fill_uniqueid(sb, &fattr);
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*pinode = cifs_iget(sb, &fattr);
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if (!*pinode) {
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rc = -ENOMEM;
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goto posix_open_ret;
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}
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} else {
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cifs_fattr_to_inode(*pinode, &fattr);
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}
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posix_open_ret:
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kfree(presp_data);
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return rc;
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}
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static int
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cifs_nt_open(char *full_path, struct inode *inode, struct cifs_sb_info *cifs_sb,
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struct cifs_tcon *tcon, unsigned int f_flags, __u32 *oplock,
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struct cifs_fid *fid, unsigned int xid)
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{
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int rc;
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int desired_access;
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int disposition;
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int create_options = CREATE_NOT_DIR;
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FILE_ALL_INFO *buf;
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struct TCP_Server_Info *server = tcon->ses->server;
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struct cifs_open_parms oparms;
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if (!server->ops->open)
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return -ENOSYS;
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desired_access = cifs_convert_flags(f_flags);
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/*********************************************************************
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* open flag mapping table:
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*
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* POSIX Flag CIFS Disposition
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* ---------- ----------------
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* O_CREAT FILE_OPEN_IF
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* O_CREAT | O_EXCL FILE_CREATE
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* O_CREAT | O_TRUNC FILE_OVERWRITE_IF
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* O_TRUNC FILE_OVERWRITE
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* none of the above FILE_OPEN
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*
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* Note that there is not a direct match between disposition
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* FILE_SUPERSEDE (ie create whether or not file exists although
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* O_CREAT | O_TRUNC is similar but truncates the existing
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* file rather than creating a new file as FILE_SUPERSEDE does
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* (which uses the attributes / metadata passed in on open call)
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*?
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*? O_SYNC is a reasonable match to CIFS writethrough flag
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*? and the read write flags match reasonably. O_LARGEFILE
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*? is irrelevant because largefile support is always used
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*? by this client. Flags O_APPEND, O_DIRECT, O_DIRECTORY,
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* O_FASYNC, O_NOFOLLOW, O_NONBLOCK need further investigation
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*********************************************************************/
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disposition = cifs_get_disposition(f_flags);
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/* BB pass O_SYNC flag through on file attributes .. BB */
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buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
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if (!buf)
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return -ENOMEM;
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if (backup_cred(cifs_sb))
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create_options |= CREATE_OPEN_BACKUP_INTENT;
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oparms.tcon = tcon;
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oparms.cifs_sb = cifs_sb;
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oparms.desired_access = desired_access;
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oparms.create_options = create_options;
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oparms.disposition = disposition;
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oparms.path = full_path;
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oparms.fid = fid;
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oparms.reconnect = false;
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rc = server->ops->open(xid, &oparms, oplock, buf);
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if (rc)
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goto out;
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if (tcon->unix_ext)
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rc = cifs_get_inode_info_unix(&inode, full_path, inode->i_sb,
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xid);
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else
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rc = cifs_get_inode_info(&inode, full_path, buf, inode->i_sb,
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xid, fid);
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out:
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kfree(buf);
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return rc;
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}
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static bool
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cifs_has_mand_locks(struct cifsInodeInfo *cinode)
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{
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struct cifs_fid_locks *cur;
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bool has_locks = false;
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down_read(&cinode->lock_sem);
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list_for_each_entry(cur, &cinode->llist, llist) {
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if (!list_empty(&cur->locks)) {
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has_locks = true;
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break;
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}
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}
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up_read(&cinode->lock_sem);
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return has_locks;
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}
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struct cifsFileInfo *
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cifs_new_fileinfo(struct cifs_fid *fid, struct file *file,
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struct tcon_link *tlink, __u32 oplock)
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{
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struct dentry *dentry = file->f_path.dentry;
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struct inode *inode = dentry->d_inode;
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struct cifsInodeInfo *cinode = CIFS_I(inode);
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struct cifsFileInfo *cfile;
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struct cifs_fid_locks *fdlocks;
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struct cifs_tcon *tcon = tlink_tcon(tlink);
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struct TCP_Server_Info *server = tcon->ses->server;
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cfile = kzalloc(sizeof(struct cifsFileInfo), GFP_KERNEL);
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if (cfile == NULL)
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return cfile;
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fdlocks = kzalloc(sizeof(struct cifs_fid_locks), GFP_KERNEL);
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if (!fdlocks) {
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kfree(cfile);
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return NULL;
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}
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INIT_LIST_HEAD(&fdlocks->locks);
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fdlocks->cfile = cfile;
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cfile->llist = fdlocks;
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down_write(&cinode->lock_sem);
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list_add(&fdlocks->llist, &cinode->llist);
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up_write(&cinode->lock_sem);
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cfile->count = 1;
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cfile->pid = current->tgid;
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cfile->uid = current_fsuid();
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cfile->dentry = dget(dentry);
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cfile->f_flags = file->f_flags;
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cfile->invalidHandle = false;
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cfile->tlink = cifs_get_tlink(tlink);
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INIT_WORK(&cfile->oplock_break, cifs_oplock_break);
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mutex_init(&cfile->fh_mutex);
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cifs_sb_active(inode->i_sb);
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/*
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* If the server returned a read oplock and we have mandatory brlocks,
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* set oplock level to None.
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*/
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if (server->ops->is_read_op(oplock) && cifs_has_mand_locks(cinode)) {
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cifs_dbg(FYI, "Reset oplock val from read to None due to mand locks\n");
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oplock = 0;
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}
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spin_lock(&cifs_file_list_lock);
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if (fid->pending_open->oplock != CIFS_OPLOCK_NO_CHANGE && oplock)
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oplock = fid->pending_open->oplock;
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list_del(&fid->pending_open->olist);
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fid->purge_cache = false;
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server->ops->set_fid(cfile, fid, oplock);
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|
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list_add(&cfile->tlist, &tcon->openFileList);
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/* if readable file instance put first in list*/
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if (file->f_mode & FMODE_READ)
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list_add(&cfile->flist, &cinode->openFileList);
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else
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list_add_tail(&cfile->flist, &cinode->openFileList);
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spin_unlock(&cifs_file_list_lock);
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if (fid->purge_cache)
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cifs_zap_mapping(inode);
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file->private_data = cfile;
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return cfile;
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}
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struct cifsFileInfo *
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cifsFileInfo_get(struct cifsFileInfo *cifs_file)
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{
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spin_lock(&cifs_file_list_lock);
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cifsFileInfo_get_locked(cifs_file);
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spin_unlock(&cifs_file_list_lock);
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return cifs_file;
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}
|
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|
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/*
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* Release a reference on the file private data. This may involve closing
|
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* the filehandle out on the server. Must be called without holding
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* cifs_file_list_lock.
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*/
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void cifsFileInfo_put(struct cifsFileInfo *cifs_file)
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{
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struct inode *inode = cifs_file->dentry->d_inode;
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struct cifs_tcon *tcon = tlink_tcon(cifs_file->tlink);
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struct TCP_Server_Info *server = tcon->ses->server;
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struct cifsInodeInfo *cifsi = CIFS_I(inode);
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struct super_block *sb = inode->i_sb;
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struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
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struct cifsLockInfo *li, *tmp;
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struct cifs_fid fid;
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struct cifs_pending_open open;
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bool oplock_break_cancelled;
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|
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spin_lock(&cifs_file_list_lock);
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if (--cifs_file->count > 0) {
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spin_unlock(&cifs_file_list_lock);
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return;
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}
|
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|
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if (server->ops->get_lease_key)
|
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server->ops->get_lease_key(inode, &fid);
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|
|
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/* store open in pending opens to make sure we don't miss lease break */
|
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cifs_add_pending_open_locked(&fid, cifs_file->tlink, &open);
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|
|
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/* remove it from the lists */
|
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list_del(&cifs_file->flist);
|
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list_del(&cifs_file->tlist);
|
|
|
|
if (list_empty(&cifsi->openFileList)) {
|
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cifs_dbg(FYI, "closing last open instance for inode %p\n",
|
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cifs_file->dentry->d_inode);
|
|
/*
|
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* In strict cache mode we need invalidate mapping on the last
|
|
* close because it may cause a error when we open this file
|
|
* again and get at least level II oplock.
|
|
*/
|
|
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_STRICT_IO)
|
|
set_bit(CIFS_INO_INVALID_MAPPING, &cifsi->flags);
|
|
cifs_set_oplock_level(cifsi, 0);
|
|
}
|
|
spin_unlock(&cifs_file_list_lock);
|
|
|
|
oplock_break_cancelled = cancel_work_sync(&cifs_file->oplock_break);
|
|
|
|
if (!tcon->need_reconnect && !cifs_file->invalidHandle) {
|
|
struct TCP_Server_Info *server = tcon->ses->server;
|
|
unsigned int xid;
|
|
|
|
xid = get_xid();
|
|
if (server->ops->close)
|
|
server->ops->close(xid, tcon, &cifs_file->fid);
|
|
_free_xid(xid);
|
|
}
|
|
|
|
if (oplock_break_cancelled)
|
|
cifs_done_oplock_break(cifsi);
|
|
|
|
cifs_del_pending_open(&open);
|
|
|
|
/*
|
|
* Delete any outstanding lock records. We'll lose them when the file
|
|
* is closed anyway.
|
|
*/
|
|
down_write(&cifsi->lock_sem);
|
|
list_for_each_entry_safe(li, tmp, &cifs_file->llist->locks, llist) {
|
|
list_del(&li->llist);
|
|
cifs_del_lock_waiters(li);
|
|
kfree(li);
|
|
}
|
|
list_del(&cifs_file->llist->llist);
|
|
kfree(cifs_file->llist);
|
|
up_write(&cifsi->lock_sem);
|
|
|
|
cifs_put_tlink(cifs_file->tlink);
|
|
dput(cifs_file->dentry);
|
|
cifs_sb_deactive(sb);
|
|
kfree(cifs_file);
|
|
}
|
|
|
|
int cifs_open(struct inode *inode, struct file *file)
|
|
|
|
{
|
|
int rc = -EACCES;
|
|
unsigned int xid;
|
|
__u32 oplock;
|
|
struct cifs_sb_info *cifs_sb;
|
|
struct TCP_Server_Info *server;
|
|
struct cifs_tcon *tcon;
|
|
struct tcon_link *tlink;
|
|
struct cifsFileInfo *cfile = NULL;
|
|
char *full_path = NULL;
|
|
bool posix_open_ok = false;
|
|
struct cifs_fid fid;
|
|
struct cifs_pending_open open;
|
|
|
|
xid = get_xid();
|
|
|
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cifs_sb = CIFS_SB(inode->i_sb);
|
|
tlink = cifs_sb_tlink(cifs_sb);
|
|
if (IS_ERR(tlink)) {
|
|
free_xid(xid);
|
|
return PTR_ERR(tlink);
|
|
}
|
|
tcon = tlink_tcon(tlink);
|
|
server = tcon->ses->server;
|
|
|
|
full_path = build_path_from_dentry(file->f_path.dentry);
|
|
if (full_path == NULL) {
|
|
rc = -ENOMEM;
|
|
goto out;
|
|
}
|
|
|
|
cifs_dbg(FYI, "inode = 0x%p file flags are 0x%x for %s\n",
|
|
inode, file->f_flags, full_path);
|
|
|
|
if (file->f_flags & O_DIRECT &&
|
|
cifs_sb->mnt_cifs_flags & CIFS_MOUNT_STRICT_IO) {
|
|
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
|
|
file->f_op = &cifs_file_direct_nobrl_ops;
|
|
else
|
|
file->f_op = &cifs_file_direct_ops;
|
|
}
|
|
|
|
if (server->oplocks)
|
|
oplock = REQ_OPLOCK;
|
|
else
|
|
oplock = 0;
|
|
|
|
if (!tcon->broken_posix_open && tcon->unix_ext &&
|
|
cap_unix(tcon->ses) && (CIFS_UNIX_POSIX_PATH_OPS_CAP &
|
|
le64_to_cpu(tcon->fsUnixInfo.Capability))) {
|
|
/* can not refresh inode info since size could be stale */
|
|
rc = cifs_posix_open(full_path, &inode, inode->i_sb,
|
|
cifs_sb->mnt_file_mode /* ignored */,
|
|
file->f_flags, &oplock, &fid.netfid, xid);
|
|
if (rc == 0) {
|
|
cifs_dbg(FYI, "posix open succeeded\n");
|
|
posix_open_ok = true;
|
|
} else if ((rc == -EINVAL) || (rc == -EOPNOTSUPP)) {
|
|
if (tcon->ses->serverNOS)
|
|
cifs_dbg(VFS, "server %s of type %s returned unexpected error on SMB posix open, disabling posix open support. Check if server update available.\n",
|
|
tcon->ses->serverName,
|
|
tcon->ses->serverNOS);
|
|
tcon->broken_posix_open = true;
|
|
} else if ((rc != -EIO) && (rc != -EREMOTE) &&
|
|
(rc != -EOPNOTSUPP)) /* path not found or net err */
|
|
goto out;
|
|
/*
|
|
* Else fallthrough to retry open the old way on network i/o
|
|
* or DFS errors.
|
|
*/
|
|
}
|
|
|
|
if (server->ops->get_lease_key)
|
|
server->ops->get_lease_key(inode, &fid);
|
|
|
|
cifs_add_pending_open(&fid, tlink, &open);
|
|
|
|
if (!posix_open_ok) {
|
|
if (server->ops->get_lease_key)
|
|
server->ops->get_lease_key(inode, &fid);
|
|
|
|
rc = cifs_nt_open(full_path, inode, cifs_sb, tcon,
|
|
file->f_flags, &oplock, &fid, xid);
|
|
if (rc) {
|
|
cifs_del_pending_open(&open);
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
cfile = cifs_new_fileinfo(&fid, file, tlink, oplock);
|
|
if (cfile == NULL) {
|
|
if (server->ops->close)
|
|
server->ops->close(xid, tcon, &fid);
|
|
cifs_del_pending_open(&open);
|
|
rc = -ENOMEM;
|
|
goto out;
|
|
}
|
|
|
|
cifs_fscache_set_inode_cookie(inode, file);
|
|
|
|
if ((oplock & CIFS_CREATE_ACTION) && !posix_open_ok && tcon->unix_ext) {
|
|
/*
|
|
* Time to set mode which we can not set earlier due to
|
|
* problems creating new read-only files.
|
|
*/
|
|
struct cifs_unix_set_info_args args = {
|
|
.mode = inode->i_mode,
|
|
.uid = INVALID_UID, /* no change */
|
|
.gid = INVALID_GID, /* no change */
|
|
.ctime = NO_CHANGE_64,
|
|
.atime = NO_CHANGE_64,
|
|
.mtime = NO_CHANGE_64,
|
|
.device = 0,
|
|
};
|
|
CIFSSMBUnixSetFileInfo(xid, tcon, &args, fid.netfid,
|
|
cfile->pid);
|
|
}
|
|
|
|
out:
|
|
kfree(full_path);
|
|
free_xid(xid);
|
|
cifs_put_tlink(tlink);
|
|
return rc;
|
|
}
|
|
|
|
static int cifs_push_posix_locks(struct cifsFileInfo *cfile);
|
|
|
|
/*
|
|
* Try to reacquire byte range locks that were released when session
|
|
* to server was lost.
|
|
*/
|
|
static int
|
|
cifs_relock_file(struct cifsFileInfo *cfile)
|
|
{
|
|
struct cifs_sb_info *cifs_sb = CIFS_SB(cfile->dentry->d_sb);
|
|
struct cifsInodeInfo *cinode = CIFS_I(cfile->dentry->d_inode);
|
|
struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
|
|
int rc = 0;
|
|
|
|
down_read(&cinode->lock_sem);
|
|
if (cinode->can_cache_brlcks) {
|
|
/* can cache locks - no need to relock */
|
|
up_read(&cinode->lock_sem);
|
|
return rc;
|
|
}
|
|
|
|
if (cap_unix(tcon->ses) &&
|
|
(CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) &&
|
|
((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0))
|
|
rc = cifs_push_posix_locks(cfile);
|
|
else
|
|
rc = tcon->ses->server->ops->push_mand_locks(cfile);
|
|
|
|
up_read(&cinode->lock_sem);
|
|
return rc;
|
|
}
|
|
|
|
static int
|
|
cifs_reopen_file(struct cifsFileInfo *cfile, bool can_flush)
|
|
{
|
|
int rc = -EACCES;
|
|
unsigned int xid;
|
|
__u32 oplock;
|
|
struct cifs_sb_info *cifs_sb;
|
|
struct cifs_tcon *tcon;
|
|
struct TCP_Server_Info *server;
|
|
struct cifsInodeInfo *cinode;
|
|
struct inode *inode;
|
|
char *full_path = NULL;
|
|
int desired_access;
|
|
int disposition = FILE_OPEN;
|
|
int create_options = CREATE_NOT_DIR;
|
|
struct cifs_open_parms oparms;
|
|
|
|
xid = get_xid();
|
|
mutex_lock(&cfile->fh_mutex);
|
|
if (!cfile->invalidHandle) {
|
|
mutex_unlock(&cfile->fh_mutex);
|
|
rc = 0;
|
|
free_xid(xid);
|
|
return rc;
|
|
}
|
|
|
|
inode = cfile->dentry->d_inode;
|
|
cifs_sb = CIFS_SB(inode->i_sb);
|
|
tcon = tlink_tcon(cfile->tlink);
|
|
server = tcon->ses->server;
|
|
|
|
/*
|
|
* Can not grab rename sem here because various ops, including those
|
|
* that already have the rename sem can end up causing writepage to get
|
|
* called and if the server was down that means we end up here, and we
|
|
* can never tell if the caller already has the rename_sem.
|
|
*/
|
|
full_path = build_path_from_dentry(cfile->dentry);
|
|
if (full_path == NULL) {
|
|
rc = -ENOMEM;
|
|
mutex_unlock(&cfile->fh_mutex);
|
|
free_xid(xid);
|
|
return rc;
|
|
}
|
|
|
|
cifs_dbg(FYI, "inode = 0x%p file flags 0x%x for %s\n",
|
|
inode, cfile->f_flags, full_path);
|
|
|
|
if (tcon->ses->server->oplocks)
|
|
oplock = REQ_OPLOCK;
|
|
else
|
|
oplock = 0;
|
|
|
|
if (tcon->unix_ext && cap_unix(tcon->ses) &&
|
|
(CIFS_UNIX_POSIX_PATH_OPS_CAP &
|
|
le64_to_cpu(tcon->fsUnixInfo.Capability))) {
|
|
/*
|
|
* O_CREAT, O_EXCL and O_TRUNC already had their effect on the
|
|
* original open. Must mask them off for a reopen.
|
|
*/
|
|
unsigned int oflags = cfile->f_flags &
|
|
~(O_CREAT | O_EXCL | O_TRUNC);
|
|
|
|
rc = cifs_posix_open(full_path, NULL, inode->i_sb,
|
|
cifs_sb->mnt_file_mode /* ignored */,
|
|
oflags, &oplock, &cfile->fid.netfid, xid);
|
|
if (rc == 0) {
|
|
cifs_dbg(FYI, "posix reopen succeeded\n");
|
|
oparms.reconnect = true;
|
|
goto reopen_success;
|
|
}
|
|
/*
|
|
* fallthrough to retry open the old way on errors, especially
|
|
* in the reconnect path it is important to retry hard
|
|
*/
|
|
}
|
|
|
|
desired_access = cifs_convert_flags(cfile->f_flags);
|
|
|
|
if (backup_cred(cifs_sb))
|
|
create_options |= CREATE_OPEN_BACKUP_INTENT;
|
|
|
|
if (server->ops->get_lease_key)
|
|
server->ops->get_lease_key(inode, &cfile->fid);
|
|
|
|
oparms.tcon = tcon;
|
|
oparms.cifs_sb = cifs_sb;
|
|
oparms.desired_access = desired_access;
|
|
oparms.create_options = create_options;
|
|
oparms.disposition = disposition;
|
|
oparms.path = full_path;
|
|
oparms.fid = &cfile->fid;
|
|
oparms.reconnect = true;
|
|
|
|
/*
|
|
* Can not refresh inode by passing in file_info buf to be returned by
|
|
* ops->open and then calling get_inode_info with returned buf since
|
|
* file might have write behind data that needs to be flushed and server
|
|
* version of file size can be stale. If we knew for sure that inode was
|
|
* not dirty locally we could do this.
|
|
*/
|
|
rc = server->ops->open(xid, &oparms, &oplock, NULL);
|
|
if (rc == -ENOENT && oparms.reconnect == false) {
|
|
/* durable handle timeout is expired - open the file again */
|
|
rc = server->ops->open(xid, &oparms, &oplock, NULL);
|
|
/* indicate that we need to relock the file */
|
|
oparms.reconnect = true;
|
|
}
|
|
|
|
if (rc) {
|
|
mutex_unlock(&cfile->fh_mutex);
|
|
cifs_dbg(FYI, "cifs_reopen returned 0x%x\n", rc);
|
|
cifs_dbg(FYI, "oplock: %d\n", oplock);
|
|
goto reopen_error_exit;
|
|
}
|
|
|
|
reopen_success:
|
|
cfile->invalidHandle = false;
|
|
mutex_unlock(&cfile->fh_mutex);
|
|
cinode = CIFS_I(inode);
|
|
|
|
if (can_flush) {
|
|
rc = filemap_write_and_wait(inode->i_mapping);
|
|
mapping_set_error(inode->i_mapping, rc);
|
|
|
|
if (tcon->unix_ext)
|
|
rc = cifs_get_inode_info_unix(&inode, full_path,
|
|
inode->i_sb, xid);
|
|
else
|
|
rc = cifs_get_inode_info(&inode, full_path, NULL,
|
|
inode->i_sb, xid, NULL);
|
|
}
|
|
/*
|
|
* Else we are writing out data to server already and could deadlock if
|
|
* we tried to flush data, and since we do not know if we have data that
|
|
* would invalidate the current end of file on the server we can not go
|
|
* to the server to get the new inode info.
|
|
*/
|
|
|
|
server->ops->set_fid(cfile, &cfile->fid, oplock);
|
|
if (oparms.reconnect)
|
|
cifs_relock_file(cfile);
|
|
|
|
reopen_error_exit:
|
|
kfree(full_path);
|
|
free_xid(xid);
|
|
return rc;
|
|
}
|
|
|
|
int cifs_close(struct inode *inode, struct file *file)
|
|
{
|
|
if (file->private_data != NULL) {
|
|
cifsFileInfo_put(file->private_data);
|
|
file->private_data = NULL;
|
|
}
|
|
|
|
/* return code from the ->release op is always ignored */
|
|
return 0;
|
|
}
|
|
|
|
int cifs_closedir(struct inode *inode, struct file *file)
|
|
{
|
|
int rc = 0;
|
|
unsigned int xid;
|
|
struct cifsFileInfo *cfile = file->private_data;
|
|
struct cifs_tcon *tcon;
|
|
struct TCP_Server_Info *server;
|
|
char *buf;
|
|
|
|
cifs_dbg(FYI, "Closedir inode = 0x%p\n", inode);
|
|
|
|
if (cfile == NULL)
|
|
return rc;
|
|
|
|
xid = get_xid();
|
|
tcon = tlink_tcon(cfile->tlink);
|
|
server = tcon->ses->server;
|
|
|
|
cifs_dbg(FYI, "Freeing private data in close dir\n");
|
|
spin_lock(&cifs_file_list_lock);
|
|
if (server->ops->dir_needs_close(cfile)) {
|
|
cfile->invalidHandle = true;
|
|
spin_unlock(&cifs_file_list_lock);
|
|
if (server->ops->close_dir)
|
|
rc = server->ops->close_dir(xid, tcon, &cfile->fid);
|
|
else
|
|
rc = -ENOSYS;
|
|
cifs_dbg(FYI, "Closing uncompleted readdir with rc %d\n", rc);
|
|
/* not much we can do if it fails anyway, ignore rc */
|
|
rc = 0;
|
|
} else
|
|
spin_unlock(&cifs_file_list_lock);
|
|
|
|
buf = cfile->srch_inf.ntwrk_buf_start;
|
|
if (buf) {
|
|
cifs_dbg(FYI, "closedir free smb buf in srch struct\n");
|
|
cfile->srch_inf.ntwrk_buf_start = NULL;
|
|
if (cfile->srch_inf.smallBuf)
|
|
cifs_small_buf_release(buf);
|
|
else
|
|
cifs_buf_release(buf);
|
|
}
|
|
|
|
cifs_put_tlink(cfile->tlink);
|
|
kfree(file->private_data);
|
|
file->private_data = NULL;
|
|
/* BB can we lock the filestruct while this is going on? */
|
|
free_xid(xid);
|
|
return rc;
|
|
}
|
|
|
|
static struct cifsLockInfo *
|
|
cifs_lock_init(__u64 offset, __u64 length, __u8 type)
|
|
{
|
|
struct cifsLockInfo *lock =
|
|
kmalloc(sizeof(struct cifsLockInfo), GFP_KERNEL);
|
|
if (!lock)
|
|
return lock;
|
|
lock->offset = offset;
|
|
lock->length = length;
|
|
lock->type = type;
|
|
lock->pid = current->tgid;
|
|
INIT_LIST_HEAD(&lock->blist);
|
|
init_waitqueue_head(&lock->block_q);
|
|
return lock;
|
|
}
|
|
|
|
void
|
|
cifs_del_lock_waiters(struct cifsLockInfo *lock)
|
|
{
|
|
struct cifsLockInfo *li, *tmp;
|
|
list_for_each_entry_safe(li, tmp, &lock->blist, blist) {
|
|
list_del_init(&li->blist);
|
|
wake_up(&li->block_q);
|
|
}
|
|
}
|
|
|
|
#define CIFS_LOCK_OP 0
|
|
#define CIFS_READ_OP 1
|
|
#define CIFS_WRITE_OP 2
|
|
|
|
/* @rw_check : 0 - no op, 1 - read, 2 - write */
|
|
static bool
|
|
cifs_find_fid_lock_conflict(struct cifs_fid_locks *fdlocks, __u64 offset,
|
|
__u64 length, __u8 type, struct cifsFileInfo *cfile,
|
|
struct cifsLockInfo **conf_lock, int rw_check)
|
|
{
|
|
struct cifsLockInfo *li;
|
|
struct cifsFileInfo *cur_cfile = fdlocks->cfile;
|
|
struct TCP_Server_Info *server = tlink_tcon(cfile->tlink)->ses->server;
|
|
|
|
list_for_each_entry(li, &fdlocks->locks, llist) {
|
|
if (offset + length <= li->offset ||
|
|
offset >= li->offset + li->length)
|
|
continue;
|
|
if (rw_check != CIFS_LOCK_OP && current->tgid == li->pid &&
|
|
server->ops->compare_fids(cfile, cur_cfile)) {
|
|
/* shared lock prevents write op through the same fid */
|
|
if (!(li->type & server->vals->shared_lock_type) ||
|
|
rw_check != CIFS_WRITE_OP)
|
|
continue;
|
|
}
|
|
if ((type & server->vals->shared_lock_type) &&
|
|
((server->ops->compare_fids(cfile, cur_cfile) &&
|
|
current->tgid == li->pid) || type == li->type))
|
|
continue;
|
|
if (conf_lock)
|
|
*conf_lock = li;
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
bool
|
|
cifs_find_lock_conflict(struct cifsFileInfo *cfile, __u64 offset, __u64 length,
|
|
__u8 type, struct cifsLockInfo **conf_lock,
|
|
int rw_check)
|
|
{
|
|
bool rc = false;
|
|
struct cifs_fid_locks *cur;
|
|
struct cifsInodeInfo *cinode = CIFS_I(cfile->dentry->d_inode);
|
|
|
|
list_for_each_entry(cur, &cinode->llist, llist) {
|
|
rc = cifs_find_fid_lock_conflict(cur, offset, length, type,
|
|
cfile, conf_lock, rw_check);
|
|
if (rc)
|
|
break;
|
|
}
|
|
|
|
return rc;
|
|
}
|
|
|
|
/*
|
|
* Check if there is another lock that prevents us to set the lock (mandatory
|
|
* style). If such a lock exists, update the flock structure with its
|
|
* properties. Otherwise, set the flock type to F_UNLCK if we can cache brlocks
|
|
* or leave it the same if we can't. Returns 0 if we don't need to request to
|
|
* the server or 1 otherwise.
|
|
*/
|
|
static int
|
|
cifs_lock_test(struct cifsFileInfo *cfile, __u64 offset, __u64 length,
|
|
__u8 type, struct file_lock *flock)
|
|
{
|
|
int rc = 0;
|
|
struct cifsLockInfo *conf_lock;
|
|
struct cifsInodeInfo *cinode = CIFS_I(cfile->dentry->d_inode);
|
|
struct TCP_Server_Info *server = tlink_tcon(cfile->tlink)->ses->server;
|
|
bool exist;
|
|
|
|
down_read(&cinode->lock_sem);
|
|
|
|
exist = cifs_find_lock_conflict(cfile, offset, length, type,
|
|
&conf_lock, CIFS_LOCK_OP);
|
|
if (exist) {
|
|
flock->fl_start = conf_lock->offset;
|
|
flock->fl_end = conf_lock->offset + conf_lock->length - 1;
|
|
flock->fl_pid = conf_lock->pid;
|
|
if (conf_lock->type & server->vals->shared_lock_type)
|
|
flock->fl_type = F_RDLCK;
|
|
else
|
|
flock->fl_type = F_WRLCK;
|
|
} else if (!cinode->can_cache_brlcks)
|
|
rc = 1;
|
|
else
|
|
flock->fl_type = F_UNLCK;
|
|
|
|
up_read(&cinode->lock_sem);
|
|
return rc;
|
|
}
|
|
|
|
static void
|
|
cifs_lock_add(struct cifsFileInfo *cfile, struct cifsLockInfo *lock)
|
|
{
|
|
struct cifsInodeInfo *cinode = CIFS_I(cfile->dentry->d_inode);
|
|
down_write(&cinode->lock_sem);
|
|
list_add_tail(&lock->llist, &cfile->llist->locks);
|
|
up_write(&cinode->lock_sem);
|
|
}
|
|
|
|
/*
|
|
* Set the byte-range lock (mandatory style). Returns:
|
|
* 1) 0, if we set the lock and don't need to request to the server;
|
|
* 2) 1, if no locks prevent us but we need to request to the server;
|
|
* 3) -EACCESS, if there is a lock that prevents us and wait is false.
|
|
*/
|
|
static int
|
|
cifs_lock_add_if(struct cifsFileInfo *cfile, struct cifsLockInfo *lock,
|
|
bool wait)
|
|
{
|
|
struct cifsLockInfo *conf_lock;
|
|
struct cifsInodeInfo *cinode = CIFS_I(cfile->dentry->d_inode);
|
|
bool exist;
|
|
int rc = 0;
|
|
|
|
try_again:
|
|
exist = false;
|
|
down_write(&cinode->lock_sem);
|
|
|
|
exist = cifs_find_lock_conflict(cfile, lock->offset, lock->length,
|
|
lock->type, &conf_lock, CIFS_LOCK_OP);
|
|
if (!exist && cinode->can_cache_brlcks) {
|
|
list_add_tail(&lock->llist, &cfile->llist->locks);
|
|
up_write(&cinode->lock_sem);
|
|
return rc;
|
|
}
|
|
|
|
if (!exist)
|
|
rc = 1;
|
|
else if (!wait)
|
|
rc = -EACCES;
|
|
else {
|
|
list_add_tail(&lock->blist, &conf_lock->blist);
|
|
up_write(&cinode->lock_sem);
|
|
rc = wait_event_interruptible(lock->block_q,
|
|
(lock->blist.prev == &lock->blist) &&
|
|
(lock->blist.next == &lock->blist));
|
|
if (!rc)
|
|
goto try_again;
|
|
down_write(&cinode->lock_sem);
|
|
list_del_init(&lock->blist);
|
|
}
|
|
|
|
up_write(&cinode->lock_sem);
|
|
return rc;
|
|
}
|
|
|
|
/*
|
|
* Check if there is another lock that prevents us to set the lock (posix
|
|
* style). If such a lock exists, update the flock structure with its
|
|
* properties. Otherwise, set the flock type to F_UNLCK if we can cache brlocks
|
|
* or leave it the same if we can't. Returns 0 if we don't need to request to
|
|
* the server or 1 otherwise.
|
|
*/
|
|
static int
|
|
cifs_posix_lock_test(struct file *file, struct file_lock *flock)
|
|
{
|
|
int rc = 0;
|
|
struct cifsInodeInfo *cinode = CIFS_I(file_inode(file));
|
|
unsigned char saved_type = flock->fl_type;
|
|
|
|
if ((flock->fl_flags & FL_POSIX) == 0)
|
|
return 1;
|
|
|
|
down_read(&cinode->lock_sem);
|
|
posix_test_lock(file, flock);
|
|
|
|
if (flock->fl_type == F_UNLCK && !cinode->can_cache_brlcks) {
|
|
flock->fl_type = saved_type;
|
|
rc = 1;
|
|
}
|
|
|
|
up_read(&cinode->lock_sem);
|
|
return rc;
|
|
}
|
|
|
|
/*
|
|
* Set the byte-range lock (posix style). Returns:
|
|
* 1) 0, if we set the lock and don't need to request to the server;
|
|
* 2) 1, if we need to request to the server;
|
|
* 3) <0, if the error occurs while setting the lock.
|
|
*/
|
|
static int
|
|
cifs_posix_lock_set(struct file *file, struct file_lock *flock)
|
|
{
|
|
struct cifsInodeInfo *cinode = CIFS_I(file_inode(file));
|
|
int rc = 1;
|
|
|
|
if ((flock->fl_flags & FL_POSIX) == 0)
|
|
return rc;
|
|
|
|
try_again:
|
|
down_write(&cinode->lock_sem);
|
|
if (!cinode->can_cache_brlcks) {
|
|
up_write(&cinode->lock_sem);
|
|
return rc;
|
|
}
|
|
|
|
rc = posix_lock_file(file, flock, NULL);
|
|
up_write(&cinode->lock_sem);
|
|
if (rc == FILE_LOCK_DEFERRED) {
|
|
rc = wait_event_interruptible(flock->fl_wait, !flock->fl_next);
|
|
if (!rc)
|
|
goto try_again;
|
|
posix_unblock_lock(flock);
|
|
}
|
|
return rc;
|
|
}
|
|
|
|
int
|
|
cifs_push_mandatory_locks(struct cifsFileInfo *cfile)
|
|
{
|
|
unsigned int xid;
|
|
int rc = 0, stored_rc;
|
|
struct cifsLockInfo *li, *tmp;
|
|
struct cifs_tcon *tcon;
|
|
unsigned int num, max_num, max_buf;
|
|
LOCKING_ANDX_RANGE *buf, *cur;
|
|
int types[] = {LOCKING_ANDX_LARGE_FILES,
|
|
LOCKING_ANDX_SHARED_LOCK | LOCKING_ANDX_LARGE_FILES};
|
|
int i;
|
|
|
|
xid = get_xid();
|
|
tcon = tlink_tcon(cfile->tlink);
|
|
|
|
/*
|
|
* Accessing maxBuf is racy with cifs_reconnect - need to store value
|
|
* and check it for zero before using.
|
|
*/
|
|
max_buf = tcon->ses->server->maxBuf;
|
|
if (!max_buf) {
|
|
free_xid(xid);
|
|
return -EINVAL;
|
|
}
|
|
|
|
max_num = (max_buf - sizeof(struct smb_hdr)) /
|
|
sizeof(LOCKING_ANDX_RANGE);
|
|
buf = kzalloc(max_num * sizeof(LOCKING_ANDX_RANGE), GFP_KERNEL);
|
|
if (!buf) {
|
|
free_xid(xid);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
for (i = 0; i < 2; i++) {
|
|
cur = buf;
|
|
num = 0;
|
|
list_for_each_entry_safe(li, tmp, &cfile->llist->locks, llist) {
|
|
if (li->type != types[i])
|
|
continue;
|
|
cur->Pid = cpu_to_le16(li->pid);
|
|
cur->LengthLow = cpu_to_le32((u32)li->length);
|
|
cur->LengthHigh = cpu_to_le32((u32)(li->length>>32));
|
|
cur->OffsetLow = cpu_to_le32((u32)li->offset);
|
|
cur->OffsetHigh = cpu_to_le32((u32)(li->offset>>32));
|
|
if (++num == max_num) {
|
|
stored_rc = cifs_lockv(xid, tcon,
|
|
cfile->fid.netfid,
|
|
(__u8)li->type, 0, num,
|
|
buf);
|
|
if (stored_rc)
|
|
rc = stored_rc;
|
|
cur = buf;
|
|
num = 0;
|
|
} else
|
|
cur++;
|
|
}
|
|
|
|
if (num) {
|
|
stored_rc = cifs_lockv(xid, tcon, cfile->fid.netfid,
|
|
(__u8)types[i], 0, num, buf);
|
|
if (stored_rc)
|
|
rc = stored_rc;
|
|
}
|
|
}
|
|
|
|
kfree(buf);
|
|
free_xid(xid);
|
|
return rc;
|
|
}
|
|
|
|
/* copied from fs/locks.c with a name change */
|
|
#define cifs_for_each_lock(inode, lockp) \
|
|
for (lockp = &inode->i_flock; *lockp != NULL; \
|
|
lockp = &(*lockp)->fl_next)
|
|
|
|
struct lock_to_push {
|
|
struct list_head llist;
|
|
__u64 offset;
|
|
__u64 length;
|
|
__u32 pid;
|
|
__u16 netfid;
|
|
__u8 type;
|
|
};
|
|
|
|
static int
|
|
cifs_push_posix_locks(struct cifsFileInfo *cfile)
|
|
{
|
|
struct inode *inode = cfile->dentry->d_inode;
|
|
struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
|
|
struct file_lock *flock, **before;
|
|
unsigned int count = 0, i = 0;
|
|
int rc = 0, xid, type;
|
|
struct list_head locks_to_send, *el;
|
|
struct lock_to_push *lck, *tmp;
|
|
__u64 length;
|
|
|
|
xid = get_xid();
|
|
|
|
spin_lock(&inode->i_lock);
|
|
cifs_for_each_lock(inode, before) {
|
|
if ((*before)->fl_flags & FL_POSIX)
|
|
count++;
|
|
}
|
|
spin_unlock(&inode->i_lock);
|
|
|
|
INIT_LIST_HEAD(&locks_to_send);
|
|
|
|
/*
|
|
* Allocating count locks is enough because no FL_POSIX locks can be
|
|
* added to the list while we are holding cinode->lock_sem that
|
|
* protects locking operations of this inode.
|
|
*/
|
|
for (; i < count; i++) {
|
|
lck = kmalloc(sizeof(struct lock_to_push), GFP_KERNEL);
|
|
if (!lck) {
|
|
rc = -ENOMEM;
|
|
goto err_out;
|
|
}
|
|
list_add_tail(&lck->llist, &locks_to_send);
|
|
}
|
|
|
|
el = locks_to_send.next;
|
|
spin_lock(&inode->i_lock);
|
|
cifs_for_each_lock(inode, before) {
|
|
flock = *before;
|
|
if ((flock->fl_flags & FL_POSIX) == 0)
|
|
continue;
|
|
if (el == &locks_to_send) {
|
|
/*
|
|
* The list ended. We don't have enough allocated
|
|
* structures - something is really wrong.
|
|
*/
|
|
cifs_dbg(VFS, "Can't push all brlocks!\n");
|
|
break;
|
|
}
|
|
length = 1 + flock->fl_end - flock->fl_start;
|
|
if (flock->fl_type == F_RDLCK || flock->fl_type == F_SHLCK)
|
|
type = CIFS_RDLCK;
|
|
else
|
|
type = CIFS_WRLCK;
|
|
lck = list_entry(el, struct lock_to_push, llist);
|
|
lck->pid = flock->fl_pid;
|
|
lck->netfid = cfile->fid.netfid;
|
|
lck->length = length;
|
|
lck->type = type;
|
|
lck->offset = flock->fl_start;
|
|
el = el->next;
|
|
}
|
|
spin_unlock(&inode->i_lock);
|
|
|
|
list_for_each_entry_safe(lck, tmp, &locks_to_send, llist) {
|
|
int stored_rc;
|
|
|
|
stored_rc = CIFSSMBPosixLock(xid, tcon, lck->netfid, lck->pid,
|
|
lck->offset, lck->length, NULL,
|
|
lck->type, 0);
|
|
if (stored_rc)
|
|
rc = stored_rc;
|
|
list_del(&lck->llist);
|
|
kfree(lck);
|
|
}
|
|
|
|
out:
|
|
free_xid(xid);
|
|
return rc;
|
|
err_out:
|
|
list_for_each_entry_safe(lck, tmp, &locks_to_send, llist) {
|
|
list_del(&lck->llist);
|
|
kfree(lck);
|
|
}
|
|
goto out;
|
|
}
|
|
|
|
static int
|
|
cifs_push_locks(struct cifsFileInfo *cfile)
|
|
{
|
|
struct cifs_sb_info *cifs_sb = CIFS_SB(cfile->dentry->d_sb);
|
|
struct cifsInodeInfo *cinode = CIFS_I(cfile->dentry->d_inode);
|
|
struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
|
|
int rc = 0;
|
|
|
|
/* we are going to update can_cache_brlcks here - need a write access */
|
|
down_write(&cinode->lock_sem);
|
|
if (!cinode->can_cache_brlcks) {
|
|
up_write(&cinode->lock_sem);
|
|
return rc;
|
|
}
|
|
|
|
if (cap_unix(tcon->ses) &&
|
|
(CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) &&
|
|
((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0))
|
|
rc = cifs_push_posix_locks(cfile);
|
|
else
|
|
rc = tcon->ses->server->ops->push_mand_locks(cfile);
|
|
|
|
cinode->can_cache_brlcks = false;
|
|
up_write(&cinode->lock_sem);
|
|
return rc;
|
|
}
|
|
|
|
static void
|
|
cifs_read_flock(struct file_lock *flock, __u32 *type, int *lock, int *unlock,
|
|
bool *wait_flag, struct TCP_Server_Info *server)
|
|
{
|
|
if (flock->fl_flags & FL_POSIX)
|
|
cifs_dbg(FYI, "Posix\n");
|
|
if (flock->fl_flags & FL_FLOCK)
|
|
cifs_dbg(FYI, "Flock\n");
|
|
if (flock->fl_flags & FL_SLEEP) {
|
|
cifs_dbg(FYI, "Blocking lock\n");
|
|
*wait_flag = true;
|
|
}
|
|
if (flock->fl_flags & FL_ACCESS)
|
|
cifs_dbg(FYI, "Process suspended by mandatory locking - not implemented yet\n");
|
|
if (flock->fl_flags & FL_LEASE)
|
|
cifs_dbg(FYI, "Lease on file - not implemented yet\n");
|
|
if (flock->fl_flags &
|
|
(~(FL_POSIX | FL_FLOCK | FL_SLEEP |
|
|
FL_ACCESS | FL_LEASE | FL_CLOSE)))
|
|
cifs_dbg(FYI, "Unknown lock flags 0x%x\n", flock->fl_flags);
|
|
|
|
*type = server->vals->large_lock_type;
|
|
if (flock->fl_type == F_WRLCK) {
|
|
cifs_dbg(FYI, "F_WRLCK\n");
|
|
*type |= server->vals->exclusive_lock_type;
|
|
*lock = 1;
|
|
} else if (flock->fl_type == F_UNLCK) {
|
|
cifs_dbg(FYI, "F_UNLCK\n");
|
|
*type |= server->vals->unlock_lock_type;
|
|
*unlock = 1;
|
|
/* Check if unlock includes more than one lock range */
|
|
} else if (flock->fl_type == F_RDLCK) {
|
|
cifs_dbg(FYI, "F_RDLCK\n");
|
|
*type |= server->vals->shared_lock_type;
|
|
*lock = 1;
|
|
} else if (flock->fl_type == F_EXLCK) {
|
|
cifs_dbg(FYI, "F_EXLCK\n");
|
|
*type |= server->vals->exclusive_lock_type;
|
|
*lock = 1;
|
|
} else if (flock->fl_type == F_SHLCK) {
|
|
cifs_dbg(FYI, "F_SHLCK\n");
|
|
*type |= server->vals->shared_lock_type;
|
|
*lock = 1;
|
|
} else
|
|
cifs_dbg(FYI, "Unknown type of lock\n");
|
|
}
|
|
|
|
static int
|
|
cifs_getlk(struct file *file, struct file_lock *flock, __u32 type,
|
|
bool wait_flag, bool posix_lck, unsigned int xid)
|
|
{
|
|
int rc = 0;
|
|
__u64 length = 1 + flock->fl_end - flock->fl_start;
|
|
struct cifsFileInfo *cfile = (struct cifsFileInfo *)file->private_data;
|
|
struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
|
|
struct TCP_Server_Info *server = tcon->ses->server;
|
|
__u16 netfid = cfile->fid.netfid;
|
|
|
|
if (posix_lck) {
|
|
int posix_lock_type;
|
|
|
|
rc = cifs_posix_lock_test(file, flock);
|
|
if (!rc)
|
|
return rc;
|
|
|
|
if (type & server->vals->shared_lock_type)
|
|
posix_lock_type = CIFS_RDLCK;
|
|
else
|
|
posix_lock_type = CIFS_WRLCK;
|
|
rc = CIFSSMBPosixLock(xid, tcon, netfid, current->tgid,
|
|
flock->fl_start, length, flock,
|
|
posix_lock_type, wait_flag);
|
|
return rc;
|
|
}
|
|
|
|
rc = cifs_lock_test(cfile, flock->fl_start, length, type, flock);
|
|
if (!rc)
|
|
return rc;
|
|
|
|
/* BB we could chain these into one lock request BB */
|
|
rc = server->ops->mand_lock(xid, cfile, flock->fl_start, length, type,
|
|
1, 0, false);
|
|
if (rc == 0) {
|
|
rc = server->ops->mand_lock(xid, cfile, flock->fl_start, length,
|
|
type, 0, 1, false);
|
|
flock->fl_type = F_UNLCK;
|
|
if (rc != 0)
|
|
cifs_dbg(VFS, "Error unlocking previously locked range %d during test of lock\n",
|
|
rc);
|
|
return 0;
|
|
}
|
|
|
|
if (type & server->vals->shared_lock_type) {
|
|
flock->fl_type = F_WRLCK;
|
|
return 0;
|
|
}
|
|
|
|
type &= ~server->vals->exclusive_lock_type;
|
|
|
|
rc = server->ops->mand_lock(xid, cfile, flock->fl_start, length,
|
|
type | server->vals->shared_lock_type,
|
|
1, 0, false);
|
|
if (rc == 0) {
|
|
rc = server->ops->mand_lock(xid, cfile, flock->fl_start, length,
|
|
type | server->vals->shared_lock_type, 0, 1, false);
|
|
flock->fl_type = F_RDLCK;
|
|
if (rc != 0)
|
|
cifs_dbg(VFS, "Error unlocking previously locked range %d during test of lock\n",
|
|
rc);
|
|
} else
|
|
flock->fl_type = F_WRLCK;
|
|
|
|
return 0;
|
|
}
|
|
|
|
void
|
|
cifs_move_llist(struct list_head *source, struct list_head *dest)
|
|
{
|
|
struct list_head *li, *tmp;
|
|
list_for_each_safe(li, tmp, source)
|
|
list_move(li, dest);
|
|
}
|
|
|
|
void
|
|
cifs_free_llist(struct list_head *llist)
|
|
{
|
|
struct cifsLockInfo *li, *tmp;
|
|
list_for_each_entry_safe(li, tmp, llist, llist) {
|
|
cifs_del_lock_waiters(li);
|
|
list_del(&li->llist);
|
|
kfree(li);
|
|
}
|
|
}
|
|
|
|
int
|
|
cifs_unlock_range(struct cifsFileInfo *cfile, struct file_lock *flock,
|
|
unsigned int xid)
|
|
{
|
|
int rc = 0, stored_rc;
|
|
int types[] = {LOCKING_ANDX_LARGE_FILES,
|
|
LOCKING_ANDX_SHARED_LOCK | LOCKING_ANDX_LARGE_FILES};
|
|
unsigned int i;
|
|
unsigned int max_num, num, max_buf;
|
|
LOCKING_ANDX_RANGE *buf, *cur;
|
|
struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
|
|
struct cifsInodeInfo *cinode = CIFS_I(cfile->dentry->d_inode);
|
|
struct cifsLockInfo *li, *tmp;
|
|
__u64 length = 1 + flock->fl_end - flock->fl_start;
|
|
struct list_head tmp_llist;
|
|
|
|
INIT_LIST_HEAD(&tmp_llist);
|
|
|
|
/*
|
|
* Accessing maxBuf is racy with cifs_reconnect - need to store value
|
|
* and check it for zero before using.
|
|
*/
|
|
max_buf = tcon->ses->server->maxBuf;
|
|
if (!max_buf)
|
|
return -EINVAL;
|
|
|
|
max_num = (max_buf - sizeof(struct smb_hdr)) /
|
|
sizeof(LOCKING_ANDX_RANGE);
|
|
buf = kzalloc(max_num * sizeof(LOCKING_ANDX_RANGE), GFP_KERNEL);
|
|
if (!buf)
|
|
return -ENOMEM;
|
|
|
|
down_write(&cinode->lock_sem);
|
|
for (i = 0; i < 2; i++) {
|
|
cur = buf;
|
|
num = 0;
|
|
list_for_each_entry_safe(li, tmp, &cfile->llist->locks, llist) {
|
|
if (flock->fl_start > li->offset ||
|
|
(flock->fl_start + length) <
|
|
(li->offset + li->length))
|
|
continue;
|
|
if (current->tgid != li->pid)
|
|
continue;
|
|
if (types[i] != li->type)
|
|
continue;
|
|
if (cinode->can_cache_brlcks) {
|
|
/*
|
|
* We can cache brlock requests - simply remove
|
|
* a lock from the file's list.
|
|
*/
|
|
list_del(&li->llist);
|
|
cifs_del_lock_waiters(li);
|
|
kfree(li);
|
|
continue;
|
|
}
|
|
cur->Pid = cpu_to_le16(li->pid);
|
|
cur->LengthLow = cpu_to_le32((u32)li->length);
|
|
cur->LengthHigh = cpu_to_le32((u32)(li->length>>32));
|
|
cur->OffsetLow = cpu_to_le32((u32)li->offset);
|
|
cur->OffsetHigh = cpu_to_le32((u32)(li->offset>>32));
|
|
/*
|
|
* We need to save a lock here to let us add it again to
|
|
* the file's list if the unlock range request fails on
|
|
* the server.
|
|
*/
|
|
list_move(&li->llist, &tmp_llist);
|
|
if (++num == max_num) {
|
|
stored_rc = cifs_lockv(xid, tcon,
|
|
cfile->fid.netfid,
|
|
li->type, num, 0, buf);
|
|
if (stored_rc) {
|
|
/*
|
|
* We failed on the unlock range
|
|
* request - add all locks from the tmp
|
|
* list to the head of the file's list.
|
|
*/
|
|
cifs_move_llist(&tmp_llist,
|
|
&cfile->llist->locks);
|
|
rc = stored_rc;
|
|
} else
|
|
/*
|
|
* The unlock range request succeed -
|
|
* free the tmp list.
|
|
*/
|
|
cifs_free_llist(&tmp_llist);
|
|
cur = buf;
|
|
num = 0;
|
|
} else
|
|
cur++;
|
|
}
|
|
if (num) {
|
|
stored_rc = cifs_lockv(xid, tcon, cfile->fid.netfid,
|
|
types[i], num, 0, buf);
|
|
if (stored_rc) {
|
|
cifs_move_llist(&tmp_llist,
|
|
&cfile->llist->locks);
|
|
rc = stored_rc;
|
|
} else
|
|
cifs_free_llist(&tmp_llist);
|
|
}
|
|
}
|
|
|
|
up_write(&cinode->lock_sem);
|
|
kfree(buf);
|
|
return rc;
|
|
}
|
|
|
|
static int
|
|
cifs_setlk(struct file *file, struct file_lock *flock, __u32 type,
|
|
bool wait_flag, bool posix_lck, int lock, int unlock,
|
|
unsigned int xid)
|
|
{
|
|
int rc = 0;
|
|
__u64 length = 1 + flock->fl_end - flock->fl_start;
|
|
struct cifsFileInfo *cfile = (struct cifsFileInfo *)file->private_data;
|
|
struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
|
|
struct TCP_Server_Info *server = tcon->ses->server;
|
|
struct inode *inode = cfile->dentry->d_inode;
|
|
|
|
if (posix_lck) {
|
|
int posix_lock_type;
|
|
|
|
rc = cifs_posix_lock_set(file, flock);
|
|
if (!rc || rc < 0)
|
|
return rc;
|
|
|
|
if (type & server->vals->shared_lock_type)
|
|
posix_lock_type = CIFS_RDLCK;
|
|
else
|
|
posix_lock_type = CIFS_WRLCK;
|
|
|
|
if (unlock == 1)
|
|
posix_lock_type = CIFS_UNLCK;
|
|
|
|
rc = CIFSSMBPosixLock(xid, tcon, cfile->fid.netfid,
|
|
current->tgid, flock->fl_start, length,
|
|
NULL, posix_lock_type, wait_flag);
|
|
goto out;
|
|
}
|
|
|
|
if (lock) {
|
|
struct cifsLockInfo *lock;
|
|
|
|
lock = cifs_lock_init(flock->fl_start, length, type);
|
|
if (!lock)
|
|
return -ENOMEM;
|
|
|
|
rc = cifs_lock_add_if(cfile, lock, wait_flag);
|
|
if (rc < 0) {
|
|
kfree(lock);
|
|
return rc;
|
|
}
|
|
if (!rc)
|
|
goto out;
|
|
|
|
/*
|
|
* Windows 7 server can delay breaking lease from read to None
|
|
* if we set a byte-range lock on a file - break it explicitly
|
|
* before sending the lock to the server to be sure the next
|
|
* read won't conflict with non-overlapted locks due to
|
|
* pagereading.
|
|
*/
|
|
if (!CIFS_CACHE_WRITE(CIFS_I(inode)) &&
|
|
CIFS_CACHE_READ(CIFS_I(inode))) {
|
|
cifs_zap_mapping(inode);
|
|
cifs_dbg(FYI, "Set no oplock for inode=%p due to mand locks\n",
|
|
inode);
|
|
CIFS_I(inode)->oplock = 0;
|
|
}
|
|
|
|
rc = server->ops->mand_lock(xid, cfile, flock->fl_start, length,
|
|
type, 1, 0, wait_flag);
|
|
if (rc) {
|
|
kfree(lock);
|
|
return rc;
|
|
}
|
|
|
|
cifs_lock_add(cfile, lock);
|
|
} else if (unlock)
|
|
rc = server->ops->mand_unlock_range(cfile, flock, xid);
|
|
|
|
out:
|
|
if (flock->fl_flags & FL_POSIX)
|
|
posix_lock_file_wait(file, flock);
|
|
return rc;
|
|
}
|
|
|
|
int cifs_lock(struct file *file, int cmd, struct file_lock *flock)
|
|
{
|
|
int rc, xid;
|
|
int lock = 0, unlock = 0;
|
|
bool wait_flag = false;
|
|
bool posix_lck = false;
|
|
struct cifs_sb_info *cifs_sb;
|
|
struct cifs_tcon *tcon;
|
|
struct cifsInodeInfo *cinode;
|
|
struct cifsFileInfo *cfile;
|
|
__u16 netfid;
|
|
__u32 type;
|
|
|
|
rc = -EACCES;
|
|
xid = get_xid();
|
|
|
|
cifs_dbg(FYI, "Lock parm: 0x%x flockflags: 0x%x flocktype: 0x%x start: %lld end: %lld\n",
|
|
cmd, flock->fl_flags, flock->fl_type,
|
|
flock->fl_start, flock->fl_end);
|
|
|
|
cfile = (struct cifsFileInfo *)file->private_data;
|
|
tcon = tlink_tcon(cfile->tlink);
|
|
|
|
cifs_read_flock(flock, &type, &lock, &unlock, &wait_flag,
|
|
tcon->ses->server);
|
|
|
|
cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
|
|
netfid = cfile->fid.netfid;
|
|
cinode = CIFS_I(file_inode(file));
|
|
|
|
if (cap_unix(tcon->ses) &&
|
|
(CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) &&
|
|
((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0))
|
|
posix_lck = true;
|
|
/*
|
|
* BB add code here to normalize offset and length to account for
|
|
* negative length which we can not accept over the wire.
|
|
*/
|
|
if (IS_GETLK(cmd)) {
|
|
rc = cifs_getlk(file, flock, type, wait_flag, posix_lck, xid);
|
|
free_xid(xid);
|
|
return rc;
|
|
}
|
|
|
|
if (!lock && !unlock) {
|
|
/*
|
|
* if no lock or unlock then nothing to do since we do not
|
|
* know what it is
|
|
*/
|
|
free_xid(xid);
|
|
return -EOPNOTSUPP;
|
|
}
|
|
|
|
rc = cifs_setlk(file, flock, type, wait_flag, posix_lck, lock, unlock,
|
|
xid);
|
|
free_xid(xid);
|
|
return rc;
|
|
}
|
|
|
|
/*
|
|
* update the file size (if needed) after a write. Should be called with
|
|
* the inode->i_lock held
|
|
*/
|
|
void
|
|
cifs_update_eof(struct cifsInodeInfo *cifsi, loff_t offset,
|
|
unsigned int bytes_written)
|
|
{
|
|
loff_t end_of_write = offset + bytes_written;
|
|
|
|
if (end_of_write > cifsi->server_eof)
|
|
cifsi->server_eof = end_of_write;
|
|
}
|
|
|
|
static ssize_t
|
|
cifs_write(struct cifsFileInfo *open_file, __u32 pid, const char *write_data,
|
|
size_t write_size, loff_t *offset)
|
|
{
|
|
int rc = 0;
|
|
unsigned int bytes_written = 0;
|
|
unsigned int total_written;
|
|
struct cifs_sb_info *cifs_sb;
|
|
struct cifs_tcon *tcon;
|
|
struct TCP_Server_Info *server;
|
|
unsigned int xid;
|
|
struct dentry *dentry = open_file->dentry;
|
|
struct cifsInodeInfo *cifsi = CIFS_I(dentry->d_inode);
|
|
struct cifs_io_parms io_parms;
|
|
|
|
cifs_sb = CIFS_SB(dentry->d_sb);
|
|
|
|
cifs_dbg(FYI, "write %zd bytes to offset %lld of %pd\n",
|
|
write_size, *offset, dentry);
|
|
|
|
tcon = tlink_tcon(open_file->tlink);
|
|
server = tcon->ses->server;
|
|
|
|
if (!server->ops->sync_write)
|
|
return -ENOSYS;
|
|
|
|
xid = get_xid();
|
|
|
|
for (total_written = 0; write_size > total_written;
|
|
total_written += bytes_written) {
|
|
rc = -EAGAIN;
|
|
while (rc == -EAGAIN) {
|
|
struct kvec iov[2];
|
|
unsigned int len;
|
|
|
|
if (open_file->invalidHandle) {
|
|
/* we could deadlock if we called
|
|
filemap_fdatawait from here so tell
|
|
reopen_file not to flush data to
|
|
server now */
|
|
rc = cifs_reopen_file(open_file, false);
|
|
if (rc != 0)
|
|
break;
|
|
}
|
|
|
|
len = min(server->ops->wp_retry_size(dentry->d_inode),
|
|
(unsigned int)write_size - total_written);
|
|
/* iov[0] is reserved for smb header */
|
|
iov[1].iov_base = (char *)write_data + total_written;
|
|
iov[1].iov_len = len;
|
|
io_parms.pid = pid;
|
|
io_parms.tcon = tcon;
|
|
io_parms.offset = *offset;
|
|
io_parms.length = len;
|
|
rc = server->ops->sync_write(xid, &open_file->fid,
|
|
&io_parms, &bytes_written, iov, 1);
|
|
}
|
|
if (rc || (bytes_written == 0)) {
|
|
if (total_written)
|
|
break;
|
|
else {
|
|
free_xid(xid);
|
|
return rc;
|
|
}
|
|
} else {
|
|
spin_lock(&dentry->d_inode->i_lock);
|
|
cifs_update_eof(cifsi, *offset, bytes_written);
|
|
spin_unlock(&dentry->d_inode->i_lock);
|
|
*offset += bytes_written;
|
|
}
|
|
}
|
|
|
|
cifs_stats_bytes_written(tcon, total_written);
|
|
|
|
if (total_written > 0) {
|
|
spin_lock(&dentry->d_inode->i_lock);
|
|
if (*offset > dentry->d_inode->i_size)
|
|
i_size_write(dentry->d_inode, *offset);
|
|
spin_unlock(&dentry->d_inode->i_lock);
|
|
}
|
|
mark_inode_dirty_sync(dentry->d_inode);
|
|
free_xid(xid);
|
|
return total_written;
|
|
}
|
|
|
|
struct cifsFileInfo *find_readable_file(struct cifsInodeInfo *cifs_inode,
|
|
bool fsuid_only)
|
|
{
|
|
struct cifsFileInfo *open_file = NULL;
|
|
struct cifs_sb_info *cifs_sb = CIFS_SB(cifs_inode->vfs_inode.i_sb);
|
|
|
|
/* only filter by fsuid on multiuser mounts */
|
|
if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER))
|
|
fsuid_only = false;
|
|
|
|
spin_lock(&cifs_file_list_lock);
|
|
/* we could simply get the first_list_entry since write-only entries
|
|
are always at the end of the list but since the first entry might
|
|
have a close pending, we go through the whole list */
|
|
list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
|
|
if (fsuid_only && !uid_eq(open_file->uid, current_fsuid()))
|
|
continue;
|
|
if (OPEN_FMODE(open_file->f_flags) & FMODE_READ) {
|
|
if (!open_file->invalidHandle) {
|
|
/* found a good file */
|
|
/* lock it so it will not be closed on us */
|
|
cifsFileInfo_get_locked(open_file);
|
|
spin_unlock(&cifs_file_list_lock);
|
|
return open_file;
|
|
} /* else might as well continue, and look for
|
|
another, or simply have the caller reopen it
|
|
again rather than trying to fix this handle */
|
|
} else /* write only file */
|
|
break; /* write only files are last so must be done */
|
|
}
|
|
spin_unlock(&cifs_file_list_lock);
|
|
return NULL;
|
|
}
|
|
|
|
struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *cifs_inode,
|
|
bool fsuid_only)
|
|
{
|
|
struct cifsFileInfo *open_file, *inv_file = NULL;
|
|
struct cifs_sb_info *cifs_sb;
|
|
bool any_available = false;
|
|
int rc;
|
|
unsigned int refind = 0;
|
|
|
|
/* Having a null inode here (because mapping->host was set to zero by
|
|
the VFS or MM) should not happen but we had reports of on oops (due to
|
|
it being zero) during stress testcases so we need to check for it */
|
|
|
|
if (cifs_inode == NULL) {
|
|
cifs_dbg(VFS, "Null inode passed to cifs_writeable_file\n");
|
|
dump_stack();
|
|
return NULL;
|
|
}
|
|
|
|
cifs_sb = CIFS_SB(cifs_inode->vfs_inode.i_sb);
|
|
|
|
/* only filter by fsuid on multiuser mounts */
|
|
if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER))
|
|
fsuid_only = false;
|
|
|
|
spin_lock(&cifs_file_list_lock);
|
|
refind_writable:
|
|
if (refind > MAX_REOPEN_ATT) {
|
|
spin_unlock(&cifs_file_list_lock);
|
|
return NULL;
|
|
}
|
|
list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
|
|
if (!any_available && open_file->pid != current->tgid)
|
|
continue;
|
|
if (fsuid_only && !uid_eq(open_file->uid, current_fsuid()))
|
|
continue;
|
|
if (OPEN_FMODE(open_file->f_flags) & FMODE_WRITE) {
|
|
if (!open_file->invalidHandle) {
|
|
/* found a good writable file */
|
|
cifsFileInfo_get_locked(open_file);
|
|
spin_unlock(&cifs_file_list_lock);
|
|
return open_file;
|
|
} else {
|
|
if (!inv_file)
|
|
inv_file = open_file;
|
|
}
|
|
}
|
|
}
|
|
/* couldn't find useable FH with same pid, try any available */
|
|
if (!any_available) {
|
|
any_available = true;
|
|
goto refind_writable;
|
|
}
|
|
|
|
if (inv_file) {
|
|
any_available = false;
|
|
cifsFileInfo_get_locked(inv_file);
|
|
}
|
|
|
|
spin_unlock(&cifs_file_list_lock);
|
|
|
|
if (inv_file) {
|
|
rc = cifs_reopen_file(inv_file, false);
|
|
if (!rc)
|
|
return inv_file;
|
|
else {
|
|
spin_lock(&cifs_file_list_lock);
|
|
list_move_tail(&inv_file->flist,
|
|
&cifs_inode->openFileList);
|
|
spin_unlock(&cifs_file_list_lock);
|
|
cifsFileInfo_put(inv_file);
|
|
spin_lock(&cifs_file_list_lock);
|
|
++refind;
|
|
inv_file = NULL;
|
|
goto refind_writable;
|
|
}
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static int cifs_partialpagewrite(struct page *page, unsigned from, unsigned to)
|
|
{
|
|
struct address_space *mapping = page->mapping;
|
|
loff_t offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
|
|
char *write_data;
|
|
int rc = -EFAULT;
|
|
int bytes_written = 0;
|
|
struct inode *inode;
|
|
struct cifsFileInfo *open_file;
|
|
|
|
if (!mapping || !mapping->host)
|
|
return -EFAULT;
|
|
|
|
inode = page->mapping->host;
|
|
|
|
offset += (loff_t)from;
|
|
write_data = kmap(page);
|
|
write_data += from;
|
|
|
|
if ((to > PAGE_CACHE_SIZE) || (from > to)) {
|
|
kunmap(page);
|
|
return -EIO;
|
|
}
|
|
|
|
/* racing with truncate? */
|
|
if (offset > mapping->host->i_size) {
|
|
kunmap(page);
|
|
return 0; /* don't care */
|
|
}
|
|
|
|
/* check to make sure that we are not extending the file */
|
|
if (mapping->host->i_size - offset < (loff_t)to)
|
|
to = (unsigned)(mapping->host->i_size - offset);
|
|
|
|
open_file = find_writable_file(CIFS_I(mapping->host), false);
|
|
if (open_file) {
|
|
bytes_written = cifs_write(open_file, open_file->pid,
|
|
write_data, to - from, &offset);
|
|
cifsFileInfo_put(open_file);
|
|
/* Does mm or vfs already set times? */
|
|
inode->i_atime = inode->i_mtime = current_fs_time(inode->i_sb);
|
|
if ((bytes_written > 0) && (offset))
|
|
rc = 0;
|
|
else if (bytes_written < 0)
|
|
rc = bytes_written;
|
|
} else {
|
|
cifs_dbg(FYI, "No writeable filehandles for inode\n");
|
|
rc = -EIO;
|
|
}
|
|
|
|
kunmap(page);
|
|
return rc;
|
|
}
|
|
|
|
static struct cifs_writedata *
|
|
wdata_alloc_and_fillpages(pgoff_t tofind, struct address_space *mapping,
|
|
pgoff_t end, pgoff_t *index,
|
|
unsigned int *found_pages)
|
|
{
|
|
unsigned int nr_pages;
|
|
struct page **pages;
|
|
struct cifs_writedata *wdata;
|
|
|
|
wdata = cifs_writedata_alloc((unsigned int)tofind,
|
|
cifs_writev_complete);
|
|
if (!wdata)
|
|
return NULL;
|
|
|
|
/*
|
|
* find_get_pages_tag seems to return a max of 256 on each
|
|
* iteration, so we must call it several times in order to
|
|
* fill the array or the wsize is effectively limited to
|
|
* 256 * PAGE_CACHE_SIZE.
|
|
*/
|
|
*found_pages = 0;
|
|
pages = wdata->pages;
|
|
do {
|
|
nr_pages = find_get_pages_tag(mapping, index,
|
|
PAGECACHE_TAG_DIRTY, tofind,
|
|
pages);
|
|
*found_pages += nr_pages;
|
|
tofind -= nr_pages;
|
|
pages += nr_pages;
|
|
} while (nr_pages && tofind && *index <= end);
|
|
|
|
return wdata;
|
|
}
|
|
|
|
static unsigned int
|
|
wdata_prepare_pages(struct cifs_writedata *wdata, unsigned int found_pages,
|
|
struct address_space *mapping,
|
|
struct writeback_control *wbc,
|
|
pgoff_t end, pgoff_t *index, pgoff_t *next, bool *done)
|
|
{
|
|
unsigned int nr_pages = 0, i;
|
|
struct page *page;
|
|
|
|
for (i = 0; i < found_pages; i++) {
|
|
page = wdata->pages[i];
|
|
/*
|
|
* At this point we hold neither mapping->tree_lock nor
|
|
* lock on the page itself: the page may be truncated or
|
|
* invalidated (changing page->mapping to NULL), or even
|
|
* swizzled back from swapper_space to tmpfs file
|
|
* mapping
|
|
*/
|
|
|
|
if (nr_pages == 0)
|
|
lock_page(page);
|
|
else if (!trylock_page(page))
|
|
break;
|
|
|
|
if (unlikely(page->mapping != mapping)) {
|
|
unlock_page(page);
|
|
break;
|
|
}
|
|
|
|
if (!wbc->range_cyclic && page->index > end) {
|
|
*done = true;
|
|
unlock_page(page);
|
|
break;
|
|
}
|
|
|
|
if (*next && (page->index != *next)) {
|
|
/* Not next consecutive page */
|
|
unlock_page(page);
|
|
break;
|
|
}
|
|
|
|
if (wbc->sync_mode != WB_SYNC_NONE)
|
|
wait_on_page_writeback(page);
|
|
|
|
if (PageWriteback(page) ||
|
|
!clear_page_dirty_for_io(page)) {
|
|
unlock_page(page);
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* This actually clears the dirty bit in the radix tree.
|
|
* See cifs_writepage() for more commentary.
|
|
*/
|
|
set_page_writeback(page);
|
|
if (page_offset(page) >= i_size_read(mapping->host)) {
|
|
*done = true;
|
|
unlock_page(page);
|
|
end_page_writeback(page);
|
|
break;
|
|
}
|
|
|
|
wdata->pages[i] = page;
|
|
*next = page->index + 1;
|
|
++nr_pages;
|
|
}
|
|
|
|
/* reset index to refind any pages skipped */
|
|
if (nr_pages == 0)
|
|
*index = wdata->pages[0]->index + 1;
|
|
|
|
/* put any pages we aren't going to use */
|
|
for (i = nr_pages; i < found_pages; i++) {
|
|
page_cache_release(wdata->pages[i]);
|
|
wdata->pages[i] = NULL;
|
|
}
|
|
|
|
return nr_pages;
|
|
}
|
|
|
|
static int
|
|
wdata_send_pages(struct cifs_writedata *wdata, unsigned int nr_pages,
|
|
struct address_space *mapping, struct writeback_control *wbc)
|
|
{
|
|
int rc = 0;
|
|
struct TCP_Server_Info *server;
|
|
unsigned int i;
|
|
|
|
wdata->sync_mode = wbc->sync_mode;
|
|
wdata->nr_pages = nr_pages;
|
|
wdata->offset = page_offset(wdata->pages[0]);
|
|
wdata->pagesz = PAGE_CACHE_SIZE;
|
|
wdata->tailsz = min(i_size_read(mapping->host) -
|
|
page_offset(wdata->pages[nr_pages - 1]),
|
|
(loff_t)PAGE_CACHE_SIZE);
|
|
wdata->bytes = ((nr_pages - 1) * PAGE_CACHE_SIZE) + wdata->tailsz;
|
|
|
|
if (wdata->cfile != NULL)
|
|
cifsFileInfo_put(wdata->cfile);
|
|
wdata->cfile = find_writable_file(CIFS_I(mapping->host), false);
|
|
if (!wdata->cfile) {
|
|
cifs_dbg(VFS, "No writable handles for inode\n");
|
|
rc = -EBADF;
|
|
} else {
|
|
wdata->pid = wdata->cfile->pid;
|
|
server = tlink_tcon(wdata->cfile->tlink)->ses->server;
|
|
rc = server->ops->async_writev(wdata, cifs_writedata_release);
|
|
}
|
|
|
|
for (i = 0; i < nr_pages; ++i)
|
|
unlock_page(wdata->pages[i]);
|
|
|
|
return rc;
|
|
}
|
|
|
|
static int cifs_writepages(struct address_space *mapping,
|
|
struct writeback_control *wbc)
|
|
{
|
|
struct cifs_sb_info *cifs_sb = CIFS_SB(mapping->host->i_sb);
|
|
struct TCP_Server_Info *server;
|
|
bool done = false, scanned = false, range_whole = false;
|
|
pgoff_t end, index;
|
|
struct cifs_writedata *wdata;
|
|
int rc = 0;
|
|
|
|
/*
|
|
* If wsize is smaller than the page cache size, default to writing
|
|
* one page at a time via cifs_writepage
|
|
*/
|
|
if (cifs_sb->wsize < PAGE_CACHE_SIZE)
|
|
return generic_writepages(mapping, wbc);
|
|
|
|
if (wbc->range_cyclic) {
|
|
index = mapping->writeback_index; /* Start from prev offset */
|
|
end = -1;
|
|
} else {
|
|
index = wbc->range_start >> PAGE_CACHE_SHIFT;
|
|
end = wbc->range_end >> PAGE_CACHE_SHIFT;
|
|
if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
|
|
range_whole = true;
|
|
scanned = true;
|
|
}
|
|
server = cifs_sb_master_tcon(cifs_sb)->ses->server;
|
|
retry:
|
|
while (!done && index <= end) {
|
|
unsigned int i, nr_pages, found_pages, wsize, credits;
|
|
pgoff_t next = 0, tofind, saved_index = index;
|
|
|
|
rc = server->ops->wait_mtu_credits(server, cifs_sb->wsize,
|
|
&wsize, &credits);
|
|
if (rc)
|
|
break;
|
|
|
|
tofind = min((wsize / PAGE_CACHE_SIZE) - 1, end - index) + 1;
|
|
|
|
wdata = wdata_alloc_and_fillpages(tofind, mapping, end, &index,
|
|
&found_pages);
|
|
if (!wdata) {
|
|
rc = -ENOMEM;
|
|
add_credits_and_wake_if(server, credits, 0);
|
|
break;
|
|
}
|
|
|
|
if (found_pages == 0) {
|
|
kref_put(&wdata->refcount, cifs_writedata_release);
|
|
add_credits_and_wake_if(server, credits, 0);
|
|
break;
|
|
}
|
|
|
|
nr_pages = wdata_prepare_pages(wdata, found_pages, mapping, wbc,
|
|
end, &index, &next, &done);
|
|
|
|
/* nothing to write? */
|
|
if (nr_pages == 0) {
|
|
kref_put(&wdata->refcount, cifs_writedata_release);
|
|
add_credits_and_wake_if(server, credits, 0);
|
|
continue;
|
|
}
|
|
|
|
wdata->credits = credits;
|
|
|
|
rc = wdata_send_pages(wdata, nr_pages, mapping, wbc);
|
|
|
|
/* send failure -- clean up the mess */
|
|
if (rc != 0) {
|
|
add_credits_and_wake_if(server, wdata->credits, 0);
|
|
for (i = 0; i < nr_pages; ++i) {
|
|
if (rc == -EAGAIN)
|
|
redirty_page_for_writepage(wbc,
|
|
wdata->pages[i]);
|
|
else
|
|
SetPageError(wdata->pages[i]);
|
|
end_page_writeback(wdata->pages[i]);
|
|
page_cache_release(wdata->pages[i]);
|
|
}
|
|
if (rc != -EAGAIN)
|
|
mapping_set_error(mapping, rc);
|
|
}
|
|
kref_put(&wdata->refcount, cifs_writedata_release);
|
|
|
|
if (wbc->sync_mode == WB_SYNC_ALL && rc == -EAGAIN) {
|
|
index = saved_index;
|
|
continue;
|
|
}
|
|
|
|
wbc->nr_to_write -= nr_pages;
|
|
if (wbc->nr_to_write <= 0)
|
|
done = true;
|
|
|
|
index = next;
|
|
}
|
|
|
|
if (!scanned && !done) {
|
|
/*
|
|
* We hit the last page and there is more work to be done: wrap
|
|
* back to the start of the file
|
|
*/
|
|
scanned = true;
|
|
index = 0;
|
|
goto retry;
|
|
}
|
|
|
|
if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
|
|
mapping->writeback_index = index;
|
|
|
|
return rc;
|
|
}
|
|
|
|
static int
|
|
cifs_writepage_locked(struct page *page, struct writeback_control *wbc)
|
|
{
|
|
int rc;
|
|
unsigned int xid;
|
|
|
|
xid = get_xid();
|
|
/* BB add check for wbc flags */
|
|
page_cache_get(page);
|
|
if (!PageUptodate(page))
|
|
cifs_dbg(FYI, "ppw - page not up to date\n");
|
|
|
|
/*
|
|
* Set the "writeback" flag, and clear "dirty" in the radix tree.
|
|
*
|
|
* A writepage() implementation always needs to do either this,
|
|
* or re-dirty the page with "redirty_page_for_writepage()" in
|
|
* the case of a failure.
|
|
*
|
|
* Just unlocking the page will cause the radix tree tag-bits
|
|
* to fail to update with the state of the page correctly.
|
|
*/
|
|
set_page_writeback(page);
|
|
retry_write:
|
|
rc = cifs_partialpagewrite(page, 0, PAGE_CACHE_SIZE);
|
|
if (rc == -EAGAIN && wbc->sync_mode == WB_SYNC_ALL)
|
|
goto retry_write;
|
|
else if (rc == -EAGAIN)
|
|
redirty_page_for_writepage(wbc, page);
|
|
else if (rc != 0)
|
|
SetPageError(page);
|
|
else
|
|
SetPageUptodate(page);
|
|
end_page_writeback(page);
|
|
page_cache_release(page);
|
|
free_xid(xid);
|
|
return rc;
|
|
}
|
|
|
|
static int cifs_writepage(struct page *page, struct writeback_control *wbc)
|
|
{
|
|
int rc = cifs_writepage_locked(page, wbc);
|
|
unlock_page(page);
|
|
return rc;
|
|
}
|
|
|
|
static int cifs_write_end(struct file *file, struct address_space *mapping,
|
|
loff_t pos, unsigned len, unsigned copied,
|
|
struct page *page, void *fsdata)
|
|
{
|
|
int rc;
|
|
struct inode *inode = mapping->host;
|
|
struct cifsFileInfo *cfile = file->private_data;
|
|
struct cifs_sb_info *cifs_sb = CIFS_SB(cfile->dentry->d_sb);
|
|
__u32 pid;
|
|
|
|
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
|
|
pid = cfile->pid;
|
|
else
|
|
pid = current->tgid;
|
|
|
|
cifs_dbg(FYI, "write_end for page %p from pos %lld with %d bytes\n",
|
|
page, pos, copied);
|
|
|
|
if (PageChecked(page)) {
|
|
if (copied == len)
|
|
SetPageUptodate(page);
|
|
ClearPageChecked(page);
|
|
} else if (!PageUptodate(page) && copied == PAGE_CACHE_SIZE)
|
|
SetPageUptodate(page);
|
|
|
|
if (!PageUptodate(page)) {
|
|
char *page_data;
|
|
unsigned offset = pos & (PAGE_CACHE_SIZE - 1);
|
|
unsigned int xid;
|
|
|
|
xid = get_xid();
|
|
/* this is probably better than directly calling
|
|
partialpage_write since in this function the file handle is
|
|
known which we might as well leverage */
|
|
/* BB check if anything else missing out of ppw
|
|
such as updating last write time */
|
|
page_data = kmap(page);
|
|
rc = cifs_write(cfile, pid, page_data + offset, copied, &pos);
|
|
/* if (rc < 0) should we set writebehind rc? */
|
|
kunmap(page);
|
|
|
|
free_xid(xid);
|
|
} else {
|
|
rc = copied;
|
|
pos += copied;
|
|
set_page_dirty(page);
|
|
}
|
|
|
|
if (rc > 0) {
|
|
spin_lock(&inode->i_lock);
|
|
if (pos > inode->i_size)
|
|
i_size_write(inode, pos);
|
|
spin_unlock(&inode->i_lock);
|
|
}
|
|
|
|
unlock_page(page);
|
|
page_cache_release(page);
|
|
|
|
return rc;
|
|
}
|
|
|
|
int cifs_strict_fsync(struct file *file, loff_t start, loff_t end,
|
|
int datasync)
|
|
{
|
|
unsigned int xid;
|
|
int rc = 0;
|
|
struct cifs_tcon *tcon;
|
|
struct TCP_Server_Info *server;
|
|
struct cifsFileInfo *smbfile = file->private_data;
|
|
struct inode *inode = file_inode(file);
|
|
struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
|
|
|
|
rc = filemap_write_and_wait_range(inode->i_mapping, start, end);
|
|
if (rc)
|
|
return rc;
|
|
mutex_lock(&inode->i_mutex);
|
|
|
|
xid = get_xid();
|
|
|
|
cifs_dbg(FYI, "Sync file - name: %pD datasync: 0x%x\n",
|
|
file, datasync);
|
|
|
|
if (!CIFS_CACHE_READ(CIFS_I(inode))) {
|
|
rc = cifs_zap_mapping(inode);
|
|
if (rc) {
|
|
cifs_dbg(FYI, "rc: %d during invalidate phase\n", rc);
|
|
rc = 0; /* don't care about it in fsync */
|
|
}
|
|
}
|
|
|
|
tcon = tlink_tcon(smbfile->tlink);
|
|
if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOSSYNC)) {
|
|
server = tcon->ses->server;
|
|
if (server->ops->flush)
|
|
rc = server->ops->flush(xid, tcon, &smbfile->fid);
|
|
else
|
|
rc = -ENOSYS;
|
|
}
|
|
|
|
free_xid(xid);
|
|
mutex_unlock(&inode->i_mutex);
|
|
return rc;
|
|
}
|
|
|
|
int cifs_fsync(struct file *file, loff_t start, loff_t end, int datasync)
|
|
{
|
|
unsigned int xid;
|
|
int rc = 0;
|
|
struct cifs_tcon *tcon;
|
|
struct TCP_Server_Info *server;
|
|
struct cifsFileInfo *smbfile = file->private_data;
|
|
struct cifs_sb_info *cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
|
|
struct inode *inode = file->f_mapping->host;
|
|
|
|
rc = filemap_write_and_wait_range(inode->i_mapping, start, end);
|
|
if (rc)
|
|
return rc;
|
|
mutex_lock(&inode->i_mutex);
|
|
|
|
xid = get_xid();
|
|
|
|
cifs_dbg(FYI, "Sync file - name: %pD datasync: 0x%x\n",
|
|
file, datasync);
|
|
|
|
tcon = tlink_tcon(smbfile->tlink);
|
|
if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOSSYNC)) {
|
|
server = tcon->ses->server;
|
|
if (server->ops->flush)
|
|
rc = server->ops->flush(xid, tcon, &smbfile->fid);
|
|
else
|
|
rc = -ENOSYS;
|
|
}
|
|
|
|
free_xid(xid);
|
|
mutex_unlock(&inode->i_mutex);
|
|
return rc;
|
|
}
|
|
|
|
/*
|
|
* As file closes, flush all cached write data for this inode checking
|
|
* for write behind errors.
|
|
*/
|
|
int cifs_flush(struct file *file, fl_owner_t id)
|
|
{
|
|
struct inode *inode = file_inode(file);
|
|
int rc = 0;
|
|
|
|
if (file->f_mode & FMODE_WRITE)
|
|
rc = filemap_write_and_wait(inode->i_mapping);
|
|
|
|
cifs_dbg(FYI, "Flush inode %p file %p rc %d\n", inode, file, rc);
|
|
|
|
return rc;
|
|
}
|
|
|
|
static int
|
|
cifs_write_allocate_pages(struct page **pages, unsigned long num_pages)
|
|
{
|
|
int rc = 0;
|
|
unsigned long i;
|
|
|
|
for (i = 0; i < num_pages; i++) {
|
|
pages[i] = alloc_page(GFP_KERNEL|__GFP_HIGHMEM);
|
|
if (!pages[i]) {
|
|
/*
|
|
* save number of pages we have already allocated and
|
|
* return with ENOMEM error
|
|
*/
|
|
num_pages = i;
|
|
rc = -ENOMEM;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (rc) {
|
|
for (i = 0; i < num_pages; i++)
|
|
put_page(pages[i]);
|
|
}
|
|
return rc;
|
|
}
|
|
|
|
static inline
|
|
size_t get_numpages(const size_t wsize, const size_t len, size_t *cur_len)
|
|
{
|
|
size_t num_pages;
|
|
size_t clen;
|
|
|
|
clen = min_t(const size_t, len, wsize);
|
|
num_pages = DIV_ROUND_UP(clen, PAGE_SIZE);
|
|
|
|
if (cur_len)
|
|
*cur_len = clen;
|
|
|
|
return num_pages;
|
|
}
|
|
|
|
static void
|
|
cifs_uncached_writedata_release(struct kref *refcount)
|
|
{
|
|
int i;
|
|
struct cifs_writedata *wdata = container_of(refcount,
|
|
struct cifs_writedata, refcount);
|
|
|
|
for (i = 0; i < wdata->nr_pages; i++)
|
|
put_page(wdata->pages[i]);
|
|
cifs_writedata_release(refcount);
|
|
}
|
|
|
|
static void
|
|
cifs_uncached_writev_complete(struct work_struct *work)
|
|
{
|
|
struct cifs_writedata *wdata = container_of(work,
|
|
struct cifs_writedata, work);
|
|
struct inode *inode = wdata->cfile->dentry->d_inode;
|
|
struct cifsInodeInfo *cifsi = CIFS_I(inode);
|
|
|
|
spin_lock(&inode->i_lock);
|
|
cifs_update_eof(cifsi, wdata->offset, wdata->bytes);
|
|
if (cifsi->server_eof > inode->i_size)
|
|
i_size_write(inode, cifsi->server_eof);
|
|
spin_unlock(&inode->i_lock);
|
|
|
|
complete(&wdata->done);
|
|
|
|
kref_put(&wdata->refcount, cifs_uncached_writedata_release);
|
|
}
|
|
|
|
static int
|
|
wdata_fill_from_iovec(struct cifs_writedata *wdata, struct iov_iter *from,
|
|
size_t *len, unsigned long *num_pages)
|
|
{
|
|
size_t save_len, copied, bytes, cur_len = *len;
|
|
unsigned long i, nr_pages = *num_pages;
|
|
|
|
save_len = cur_len;
|
|
for (i = 0; i < nr_pages; i++) {
|
|
bytes = min_t(const size_t, cur_len, PAGE_SIZE);
|
|
copied = copy_page_from_iter(wdata->pages[i], 0, bytes, from);
|
|
cur_len -= copied;
|
|
/*
|
|
* If we didn't copy as much as we expected, then that
|
|
* may mean we trod into an unmapped area. Stop copying
|
|
* at that point. On the next pass through the big
|
|
* loop, we'll likely end up getting a zero-length
|
|
* write and bailing out of it.
|
|
*/
|
|
if (copied < bytes)
|
|
break;
|
|
}
|
|
cur_len = save_len - cur_len;
|
|
*len = cur_len;
|
|
|
|
/*
|
|
* If we have no data to send, then that probably means that
|
|
* the copy above failed altogether. That's most likely because
|
|
* the address in the iovec was bogus. Return -EFAULT and let
|
|
* the caller free anything we allocated and bail out.
|
|
*/
|
|
if (!cur_len)
|
|
return -EFAULT;
|
|
|
|
/*
|
|
* i + 1 now represents the number of pages we actually used in
|
|
* the copy phase above.
|
|
*/
|
|
*num_pages = i + 1;
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
cifs_write_from_iter(loff_t offset, size_t len, struct iov_iter *from,
|
|
struct cifsFileInfo *open_file,
|
|
struct cifs_sb_info *cifs_sb, struct list_head *wdata_list)
|
|
{
|
|
int rc = 0;
|
|
size_t cur_len;
|
|
unsigned long nr_pages, num_pages, i;
|
|
struct cifs_writedata *wdata;
|
|
struct iov_iter saved_from;
|
|
loff_t saved_offset = offset;
|
|
pid_t pid;
|
|
struct TCP_Server_Info *server;
|
|
|
|
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
|
|
pid = open_file->pid;
|
|
else
|
|
pid = current->tgid;
|
|
|
|
server = tlink_tcon(open_file->tlink)->ses->server;
|
|
memcpy(&saved_from, from, sizeof(struct iov_iter));
|
|
|
|
do {
|
|
unsigned int wsize, credits;
|
|
|
|
rc = server->ops->wait_mtu_credits(server, cifs_sb->wsize,
|
|
&wsize, &credits);
|
|
if (rc)
|
|
break;
|
|
|
|
nr_pages = get_numpages(wsize, len, &cur_len);
|
|
wdata = cifs_writedata_alloc(nr_pages,
|
|
cifs_uncached_writev_complete);
|
|
if (!wdata) {
|
|
rc = -ENOMEM;
|
|
add_credits_and_wake_if(server, credits, 0);
|
|
break;
|
|
}
|
|
|
|
rc = cifs_write_allocate_pages(wdata->pages, nr_pages);
|
|
if (rc) {
|
|
kfree(wdata);
|
|
add_credits_and_wake_if(server, credits, 0);
|
|
break;
|
|
}
|
|
|
|
num_pages = nr_pages;
|
|
rc = wdata_fill_from_iovec(wdata, from, &cur_len, &num_pages);
|
|
if (rc) {
|
|
for (i = 0; i < nr_pages; i++)
|
|
put_page(wdata->pages[i]);
|
|
kfree(wdata);
|
|
add_credits_and_wake_if(server, credits, 0);
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* Bring nr_pages down to the number of pages we actually used,
|
|
* and free any pages that we didn't use.
|
|
*/
|
|
for ( ; nr_pages > num_pages; nr_pages--)
|
|
put_page(wdata->pages[nr_pages - 1]);
|
|
|
|
wdata->sync_mode = WB_SYNC_ALL;
|
|
wdata->nr_pages = nr_pages;
|
|
wdata->offset = (__u64)offset;
|
|
wdata->cfile = cifsFileInfo_get(open_file);
|
|
wdata->pid = pid;
|
|
wdata->bytes = cur_len;
|
|
wdata->pagesz = PAGE_SIZE;
|
|
wdata->tailsz = cur_len - ((nr_pages - 1) * PAGE_SIZE);
|
|
wdata->credits = credits;
|
|
|
|
if (!wdata->cfile->invalidHandle ||
|
|
!cifs_reopen_file(wdata->cfile, false))
|
|
rc = server->ops->async_writev(wdata,
|
|
cifs_uncached_writedata_release);
|
|
if (rc) {
|
|
add_credits_and_wake_if(server, wdata->credits, 0);
|
|
kref_put(&wdata->refcount,
|
|
cifs_uncached_writedata_release);
|
|
if (rc == -EAGAIN) {
|
|
memcpy(from, &saved_from,
|
|
sizeof(struct iov_iter));
|
|
iov_iter_advance(from, offset - saved_offset);
|
|
continue;
|
|
}
|
|
break;
|
|
}
|
|
|
|
list_add_tail(&wdata->list, wdata_list);
|
|
offset += cur_len;
|
|
len -= cur_len;
|
|
} while (len > 0);
|
|
|
|
return rc;
|
|
}
|
|
|
|
static ssize_t
|
|
cifs_iovec_write(struct file *file, struct iov_iter *from, loff_t *poffset)
|
|
{
|
|
size_t len;
|
|
ssize_t total_written = 0;
|
|
struct cifsFileInfo *open_file;
|
|
struct cifs_tcon *tcon;
|
|
struct cifs_sb_info *cifs_sb;
|
|
struct cifs_writedata *wdata, *tmp;
|
|
struct list_head wdata_list;
|
|
struct iov_iter saved_from;
|
|
int rc;
|
|
|
|
len = iov_iter_count(from);
|
|
rc = generic_write_checks(file, poffset, &len, 0);
|
|
if (rc)
|
|
return rc;
|
|
|
|
if (!len)
|
|
return 0;
|
|
|
|
iov_iter_truncate(from, len);
|
|
|
|
INIT_LIST_HEAD(&wdata_list);
|
|
cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
|
|
open_file = file->private_data;
|
|
tcon = tlink_tcon(open_file->tlink);
|
|
|
|
if (!tcon->ses->server->ops->async_writev)
|
|
return -ENOSYS;
|
|
|
|
memcpy(&saved_from, from, sizeof(struct iov_iter));
|
|
|
|
rc = cifs_write_from_iter(*poffset, len, from, open_file, cifs_sb,
|
|
&wdata_list);
|
|
|
|
/*
|
|
* If at least one write was successfully sent, then discard any rc
|
|
* value from the later writes. If the other write succeeds, then
|
|
* we'll end up returning whatever was written. If it fails, then
|
|
* we'll get a new rc value from that.
|
|
*/
|
|
if (!list_empty(&wdata_list))
|
|
rc = 0;
|
|
|
|
/*
|
|
* Wait for and collect replies for any successful sends in order of
|
|
* increasing offset. Once an error is hit or we get a fatal signal
|
|
* while waiting, then return without waiting for any more replies.
|
|
*/
|
|
restart_loop:
|
|
list_for_each_entry_safe(wdata, tmp, &wdata_list, list) {
|
|
if (!rc) {
|
|
/* FIXME: freezable too? */
|
|
rc = wait_for_completion_killable(&wdata->done);
|
|
if (rc)
|
|
rc = -EINTR;
|
|
else if (wdata->result)
|
|
rc = wdata->result;
|
|
else
|
|
total_written += wdata->bytes;
|
|
|
|
/* resend call if it's a retryable error */
|
|
if (rc == -EAGAIN) {
|
|
struct list_head tmp_list;
|
|
struct iov_iter tmp_from;
|
|
|
|
INIT_LIST_HEAD(&tmp_list);
|
|
list_del_init(&wdata->list);
|
|
|
|
memcpy(&tmp_from, &saved_from,
|
|
sizeof(struct iov_iter));
|
|
iov_iter_advance(&tmp_from,
|
|
wdata->offset - *poffset);
|
|
|
|
rc = cifs_write_from_iter(wdata->offset,
|
|
wdata->bytes, &tmp_from,
|
|
open_file, cifs_sb, &tmp_list);
|
|
|
|
list_splice(&tmp_list, &wdata_list);
|
|
|
|
kref_put(&wdata->refcount,
|
|
cifs_uncached_writedata_release);
|
|
goto restart_loop;
|
|
}
|
|
}
|
|
list_del_init(&wdata->list);
|
|
kref_put(&wdata->refcount, cifs_uncached_writedata_release);
|
|
}
|
|
|
|
if (total_written > 0)
|
|
*poffset += total_written;
|
|
|
|
cifs_stats_bytes_written(tcon, total_written);
|
|
return total_written ? total_written : (ssize_t)rc;
|
|
}
|
|
|
|
ssize_t cifs_user_writev(struct kiocb *iocb, struct iov_iter *from)
|
|
{
|
|
ssize_t written;
|
|
struct inode *inode;
|
|
loff_t pos = iocb->ki_pos;
|
|
|
|
inode = file_inode(iocb->ki_filp);
|
|
|
|
/*
|
|
* BB - optimize the way when signing is disabled. We can drop this
|
|
* extra memory-to-memory copying and use iovec buffers for constructing
|
|
* write request.
|
|
*/
|
|
|
|
written = cifs_iovec_write(iocb->ki_filp, from, &pos);
|
|
if (written > 0) {
|
|
set_bit(CIFS_INO_INVALID_MAPPING, &CIFS_I(inode)->flags);
|
|
iocb->ki_pos = pos;
|
|
}
|
|
|
|
return written;
|
|
}
|
|
|
|
static ssize_t
|
|
cifs_writev(struct kiocb *iocb, struct iov_iter *from)
|
|
{
|
|
struct file *file = iocb->ki_filp;
|
|
struct cifsFileInfo *cfile = (struct cifsFileInfo *)file->private_data;
|
|
struct inode *inode = file->f_mapping->host;
|
|
struct cifsInodeInfo *cinode = CIFS_I(inode);
|
|
struct TCP_Server_Info *server = tlink_tcon(cfile->tlink)->ses->server;
|
|
ssize_t rc = -EACCES;
|
|
loff_t lock_pos = iocb->ki_pos;
|
|
|
|
/*
|
|
* We need to hold the sem to be sure nobody modifies lock list
|
|
* with a brlock that prevents writing.
|
|
*/
|
|
down_read(&cinode->lock_sem);
|
|
mutex_lock(&inode->i_mutex);
|
|
if (file->f_flags & O_APPEND)
|
|
lock_pos = i_size_read(inode);
|
|
if (!cifs_find_lock_conflict(cfile, lock_pos, iov_iter_count(from),
|
|
server->vals->exclusive_lock_type, NULL,
|
|
CIFS_WRITE_OP)) {
|
|
rc = __generic_file_write_iter(iocb, from);
|
|
mutex_unlock(&inode->i_mutex);
|
|
|
|
if (rc > 0) {
|
|
ssize_t err;
|
|
|
|
err = generic_write_sync(file, iocb->ki_pos - rc, rc);
|
|
if (err < 0)
|
|
rc = err;
|
|
}
|
|
} else {
|
|
mutex_unlock(&inode->i_mutex);
|
|
}
|
|
up_read(&cinode->lock_sem);
|
|
return rc;
|
|
}
|
|
|
|
ssize_t
|
|
cifs_strict_writev(struct kiocb *iocb, struct iov_iter *from)
|
|
{
|
|
struct inode *inode = file_inode(iocb->ki_filp);
|
|
struct cifsInodeInfo *cinode = CIFS_I(inode);
|
|
struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
|
|
struct cifsFileInfo *cfile = (struct cifsFileInfo *)
|
|
iocb->ki_filp->private_data;
|
|
struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
|
|
ssize_t written;
|
|
|
|
written = cifs_get_writer(cinode);
|
|
if (written)
|
|
return written;
|
|
|
|
if (CIFS_CACHE_WRITE(cinode)) {
|
|
if (cap_unix(tcon->ses) &&
|
|
(CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability))
|
|
&& ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0)) {
|
|
written = generic_file_write_iter(iocb, from);
|
|
goto out;
|
|
}
|
|
written = cifs_writev(iocb, from);
|
|
goto out;
|
|
}
|
|
/*
|
|
* For non-oplocked files in strict cache mode we need to write the data
|
|
* to the server exactly from the pos to pos+len-1 rather than flush all
|
|
* affected pages because it may cause a error with mandatory locks on
|
|
* these pages but not on the region from pos to ppos+len-1.
|
|
*/
|
|
written = cifs_user_writev(iocb, from);
|
|
if (written > 0 && CIFS_CACHE_READ(cinode)) {
|
|
/*
|
|
* Windows 7 server can delay breaking level2 oplock if a write
|
|
* request comes - break it on the client to prevent reading
|
|
* an old data.
|
|
*/
|
|
cifs_zap_mapping(inode);
|
|
cifs_dbg(FYI, "Set no oplock for inode=%p after a write operation\n",
|
|
inode);
|
|
cinode->oplock = 0;
|
|
}
|
|
out:
|
|
cifs_put_writer(cinode);
|
|
return written;
|
|
}
|
|
|
|
static struct cifs_readdata *
|
|
cifs_readdata_alloc(unsigned int nr_pages, work_func_t complete)
|
|
{
|
|
struct cifs_readdata *rdata;
|
|
|
|
rdata = kzalloc(sizeof(*rdata) + (sizeof(struct page *) * nr_pages),
|
|
GFP_KERNEL);
|
|
if (rdata != NULL) {
|
|
kref_init(&rdata->refcount);
|
|
INIT_LIST_HEAD(&rdata->list);
|
|
init_completion(&rdata->done);
|
|
INIT_WORK(&rdata->work, complete);
|
|
}
|
|
|
|
return rdata;
|
|
}
|
|
|
|
void
|
|
cifs_readdata_release(struct kref *refcount)
|
|
{
|
|
struct cifs_readdata *rdata = container_of(refcount,
|
|
struct cifs_readdata, refcount);
|
|
|
|
if (rdata->cfile)
|
|
cifsFileInfo_put(rdata->cfile);
|
|
|
|
kfree(rdata);
|
|
}
|
|
|
|
static int
|
|
cifs_read_allocate_pages(struct cifs_readdata *rdata, unsigned int nr_pages)
|
|
{
|
|
int rc = 0;
|
|
struct page *page;
|
|
unsigned int i;
|
|
|
|
for (i = 0; i < nr_pages; i++) {
|
|
page = alloc_page(GFP_KERNEL|__GFP_HIGHMEM);
|
|
if (!page) {
|
|
rc = -ENOMEM;
|
|
break;
|
|
}
|
|
rdata->pages[i] = page;
|
|
}
|
|
|
|
if (rc) {
|
|
for (i = 0; i < nr_pages; i++) {
|
|
put_page(rdata->pages[i]);
|
|
rdata->pages[i] = NULL;
|
|
}
|
|
}
|
|
return rc;
|
|
}
|
|
|
|
static void
|
|
cifs_uncached_readdata_release(struct kref *refcount)
|
|
{
|
|
struct cifs_readdata *rdata = container_of(refcount,
|
|
struct cifs_readdata, refcount);
|
|
unsigned int i;
|
|
|
|
for (i = 0; i < rdata->nr_pages; i++) {
|
|
put_page(rdata->pages[i]);
|
|
rdata->pages[i] = NULL;
|
|
}
|
|
cifs_readdata_release(refcount);
|
|
}
|
|
|
|
/**
|
|
* cifs_readdata_to_iov - copy data from pages in response to an iovec
|
|
* @rdata: the readdata response with list of pages holding data
|
|
* @iter: destination for our data
|
|
*
|
|
* This function copies data from a list of pages in a readdata response into
|
|
* an array of iovecs. It will first calculate where the data should go
|
|
* based on the info in the readdata and then copy the data into that spot.
|
|
*/
|
|
static int
|
|
cifs_readdata_to_iov(struct cifs_readdata *rdata, struct iov_iter *iter)
|
|
{
|
|
size_t remaining = rdata->got_bytes;
|
|
unsigned int i;
|
|
|
|
for (i = 0; i < rdata->nr_pages; i++) {
|
|
struct page *page = rdata->pages[i];
|
|
size_t copy = min_t(size_t, remaining, PAGE_SIZE);
|
|
size_t written = copy_page_to_iter(page, 0, copy, iter);
|
|
remaining -= written;
|
|
if (written < copy && iov_iter_count(iter) > 0)
|
|
break;
|
|
}
|
|
return remaining ? -EFAULT : 0;
|
|
}
|
|
|
|
static void
|
|
cifs_uncached_readv_complete(struct work_struct *work)
|
|
{
|
|
struct cifs_readdata *rdata = container_of(work,
|
|
struct cifs_readdata, work);
|
|
|
|
complete(&rdata->done);
|
|
kref_put(&rdata->refcount, cifs_uncached_readdata_release);
|
|
}
|
|
|
|
static int
|
|
cifs_uncached_read_into_pages(struct TCP_Server_Info *server,
|
|
struct cifs_readdata *rdata, unsigned int len)
|
|
{
|
|
int result = 0;
|
|
unsigned int i;
|
|
unsigned int nr_pages = rdata->nr_pages;
|
|
struct kvec iov;
|
|
|
|
rdata->got_bytes = 0;
|
|
rdata->tailsz = PAGE_SIZE;
|
|
for (i = 0; i < nr_pages; i++) {
|
|
struct page *page = rdata->pages[i];
|
|
|
|
if (len >= PAGE_SIZE) {
|
|
/* enough data to fill the page */
|
|
iov.iov_base = kmap(page);
|
|
iov.iov_len = PAGE_SIZE;
|
|
cifs_dbg(FYI, "%u: iov_base=%p iov_len=%zu\n",
|
|
i, iov.iov_base, iov.iov_len);
|
|
len -= PAGE_SIZE;
|
|
} else if (len > 0) {
|
|
/* enough for partial page, fill and zero the rest */
|
|
iov.iov_base = kmap(page);
|
|
iov.iov_len = len;
|
|
cifs_dbg(FYI, "%u: iov_base=%p iov_len=%zu\n",
|
|
i, iov.iov_base, iov.iov_len);
|
|
memset(iov.iov_base + len, '\0', PAGE_SIZE - len);
|
|
rdata->tailsz = len;
|
|
len = 0;
|
|
} else {
|
|
/* no need to hold page hostage */
|
|
rdata->pages[i] = NULL;
|
|
rdata->nr_pages--;
|
|
put_page(page);
|
|
continue;
|
|
}
|
|
|
|
result = cifs_readv_from_socket(server, &iov, 1, iov.iov_len);
|
|
kunmap(page);
|
|
if (result < 0)
|
|
break;
|
|
|
|
rdata->got_bytes += result;
|
|
}
|
|
|
|
return rdata->got_bytes > 0 && result != -ECONNABORTED ?
|
|
rdata->got_bytes : result;
|
|
}
|
|
|
|
static int
|
|
cifs_send_async_read(loff_t offset, size_t len, struct cifsFileInfo *open_file,
|
|
struct cifs_sb_info *cifs_sb, struct list_head *rdata_list)
|
|
{
|
|
struct cifs_readdata *rdata;
|
|
unsigned int npages, rsize, credits;
|
|
size_t cur_len;
|
|
int rc;
|
|
pid_t pid;
|
|
struct TCP_Server_Info *server;
|
|
|
|
server = tlink_tcon(open_file->tlink)->ses->server;
|
|
|
|
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
|
|
pid = open_file->pid;
|
|
else
|
|
pid = current->tgid;
|
|
|
|
do {
|
|
rc = server->ops->wait_mtu_credits(server, cifs_sb->rsize,
|
|
&rsize, &credits);
|
|
if (rc)
|
|
break;
|
|
|
|
cur_len = min_t(const size_t, len, rsize);
|
|
npages = DIV_ROUND_UP(cur_len, PAGE_SIZE);
|
|
|
|
/* allocate a readdata struct */
|
|
rdata = cifs_readdata_alloc(npages,
|
|
cifs_uncached_readv_complete);
|
|
if (!rdata) {
|
|
add_credits_and_wake_if(server, credits, 0);
|
|
rc = -ENOMEM;
|
|
break;
|
|
}
|
|
|
|
rc = cifs_read_allocate_pages(rdata, npages);
|
|
if (rc)
|
|
goto error;
|
|
|
|
rdata->cfile = cifsFileInfo_get(open_file);
|
|
rdata->nr_pages = npages;
|
|
rdata->offset = offset;
|
|
rdata->bytes = cur_len;
|
|
rdata->pid = pid;
|
|
rdata->pagesz = PAGE_SIZE;
|
|
rdata->read_into_pages = cifs_uncached_read_into_pages;
|
|
rdata->credits = credits;
|
|
|
|
if (!rdata->cfile->invalidHandle ||
|
|
!cifs_reopen_file(rdata->cfile, true))
|
|
rc = server->ops->async_readv(rdata);
|
|
error:
|
|
if (rc) {
|
|
add_credits_and_wake_if(server, rdata->credits, 0);
|
|
kref_put(&rdata->refcount,
|
|
cifs_uncached_readdata_release);
|
|
if (rc == -EAGAIN)
|
|
continue;
|
|
break;
|
|
}
|
|
|
|
list_add_tail(&rdata->list, rdata_list);
|
|
offset += cur_len;
|
|
len -= cur_len;
|
|
} while (len > 0);
|
|
|
|
return rc;
|
|
}
|
|
|
|
ssize_t cifs_user_readv(struct kiocb *iocb, struct iov_iter *to)
|
|
{
|
|
struct file *file = iocb->ki_filp;
|
|
ssize_t rc;
|
|
size_t len;
|
|
ssize_t total_read = 0;
|
|
loff_t offset = iocb->ki_pos;
|
|
struct cifs_sb_info *cifs_sb;
|
|
struct cifs_tcon *tcon;
|
|
struct cifsFileInfo *open_file;
|
|
struct cifs_readdata *rdata, *tmp;
|
|
struct list_head rdata_list;
|
|
|
|
len = iov_iter_count(to);
|
|
if (!len)
|
|
return 0;
|
|
|
|
INIT_LIST_HEAD(&rdata_list);
|
|
cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
|
|
open_file = file->private_data;
|
|
tcon = tlink_tcon(open_file->tlink);
|
|
|
|
if (!tcon->ses->server->ops->async_readv)
|
|
return -ENOSYS;
|
|
|
|
if ((file->f_flags & O_ACCMODE) == O_WRONLY)
|
|
cifs_dbg(FYI, "attempting read on write only file instance\n");
|
|
|
|
rc = cifs_send_async_read(offset, len, open_file, cifs_sb, &rdata_list);
|
|
|
|
/* if at least one read request send succeeded, then reset rc */
|
|
if (!list_empty(&rdata_list))
|
|
rc = 0;
|
|
|
|
len = iov_iter_count(to);
|
|
/* the loop below should proceed in the order of increasing offsets */
|
|
again:
|
|
list_for_each_entry_safe(rdata, tmp, &rdata_list, list) {
|
|
if (!rc) {
|
|
/* FIXME: freezable sleep too? */
|
|
rc = wait_for_completion_killable(&rdata->done);
|
|
if (rc)
|
|
rc = -EINTR;
|
|
else if (rdata->result == -EAGAIN) {
|
|
/* resend call if it's a retryable error */
|
|
struct list_head tmp_list;
|
|
unsigned int got_bytes = rdata->got_bytes;
|
|
|
|
list_del_init(&rdata->list);
|
|
INIT_LIST_HEAD(&tmp_list);
|
|
|
|
/*
|
|
* Got a part of data and then reconnect has
|
|
* happened -- fill the buffer and continue
|
|
* reading.
|
|
*/
|
|
if (got_bytes && got_bytes < rdata->bytes) {
|
|
rc = cifs_readdata_to_iov(rdata, to);
|
|
if (rc) {
|
|
kref_put(&rdata->refcount,
|
|
cifs_uncached_readdata_release);
|
|
continue;
|
|
}
|
|
}
|
|
|
|
rc = cifs_send_async_read(
|
|
rdata->offset + got_bytes,
|
|
rdata->bytes - got_bytes,
|
|
rdata->cfile, cifs_sb,
|
|
&tmp_list);
|
|
|
|
list_splice(&tmp_list, &rdata_list);
|
|
|
|
kref_put(&rdata->refcount,
|
|
cifs_uncached_readdata_release);
|
|
goto again;
|
|
} else if (rdata->result)
|
|
rc = rdata->result;
|
|
else
|
|
rc = cifs_readdata_to_iov(rdata, to);
|
|
|
|
/* if there was a short read -- discard anything left */
|
|
if (rdata->got_bytes && rdata->got_bytes < rdata->bytes)
|
|
rc = -ENODATA;
|
|
}
|
|
list_del_init(&rdata->list);
|
|
kref_put(&rdata->refcount, cifs_uncached_readdata_release);
|
|
}
|
|
|
|
total_read = len - iov_iter_count(to);
|
|
|
|
cifs_stats_bytes_read(tcon, total_read);
|
|
|
|
/* mask nodata case */
|
|
if (rc == -ENODATA)
|
|
rc = 0;
|
|
|
|
if (total_read) {
|
|
iocb->ki_pos += total_read;
|
|
return total_read;
|
|
}
|
|
return rc;
|
|
}
|
|
|
|
ssize_t
|
|
cifs_strict_readv(struct kiocb *iocb, struct iov_iter *to)
|
|
{
|
|
struct inode *inode = file_inode(iocb->ki_filp);
|
|
struct cifsInodeInfo *cinode = CIFS_I(inode);
|
|
struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
|
|
struct cifsFileInfo *cfile = (struct cifsFileInfo *)
|
|
iocb->ki_filp->private_data;
|
|
struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
|
|
int rc = -EACCES;
|
|
|
|
/*
|
|
* In strict cache mode we need to read from the server all the time
|
|
* if we don't have level II oplock because the server can delay mtime
|
|
* change - so we can't make a decision about inode invalidating.
|
|
* And we can also fail with pagereading if there are mandatory locks
|
|
* on pages affected by this read but not on the region from pos to
|
|
* pos+len-1.
|
|
*/
|
|
if (!CIFS_CACHE_READ(cinode))
|
|
return cifs_user_readv(iocb, to);
|
|
|
|
if (cap_unix(tcon->ses) &&
|
|
(CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) &&
|
|
((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0))
|
|
return generic_file_read_iter(iocb, to);
|
|
|
|
/*
|
|
* We need to hold the sem to be sure nobody modifies lock list
|
|
* with a brlock that prevents reading.
|
|
*/
|
|
down_read(&cinode->lock_sem);
|
|
if (!cifs_find_lock_conflict(cfile, iocb->ki_pos, iov_iter_count(to),
|
|
tcon->ses->server->vals->shared_lock_type,
|
|
NULL, CIFS_READ_OP))
|
|
rc = generic_file_read_iter(iocb, to);
|
|
up_read(&cinode->lock_sem);
|
|
return rc;
|
|
}
|
|
|
|
static ssize_t
|
|
cifs_read(struct file *file, char *read_data, size_t read_size, loff_t *offset)
|
|
{
|
|
int rc = -EACCES;
|
|
unsigned int bytes_read = 0;
|
|
unsigned int total_read;
|
|
unsigned int current_read_size;
|
|
unsigned int rsize;
|
|
struct cifs_sb_info *cifs_sb;
|
|
struct cifs_tcon *tcon;
|
|
struct TCP_Server_Info *server;
|
|
unsigned int xid;
|
|
char *cur_offset;
|
|
struct cifsFileInfo *open_file;
|
|
struct cifs_io_parms io_parms;
|
|
int buf_type = CIFS_NO_BUFFER;
|
|
__u32 pid;
|
|
|
|
xid = get_xid();
|
|
cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
|
|
|
|
/* FIXME: set up handlers for larger reads and/or convert to async */
|
|
rsize = min_t(unsigned int, cifs_sb->rsize, CIFSMaxBufSize);
|
|
|
|
if (file->private_data == NULL) {
|
|
rc = -EBADF;
|
|
free_xid(xid);
|
|
return rc;
|
|
}
|
|
open_file = file->private_data;
|
|
tcon = tlink_tcon(open_file->tlink);
|
|
server = tcon->ses->server;
|
|
|
|
if (!server->ops->sync_read) {
|
|
free_xid(xid);
|
|
return -ENOSYS;
|
|
}
|
|
|
|
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
|
|
pid = open_file->pid;
|
|
else
|
|
pid = current->tgid;
|
|
|
|
if ((file->f_flags & O_ACCMODE) == O_WRONLY)
|
|
cifs_dbg(FYI, "attempting read on write only file instance\n");
|
|
|
|
for (total_read = 0, cur_offset = read_data; read_size > total_read;
|
|
total_read += bytes_read, cur_offset += bytes_read) {
|
|
do {
|
|
current_read_size = min_t(uint, read_size - total_read,
|
|
rsize);
|
|
/*
|
|
* For windows me and 9x we do not want to request more
|
|
* than it negotiated since it will refuse the read
|
|
* then.
|
|
*/
|
|
if ((tcon->ses) && !(tcon->ses->capabilities &
|
|
tcon->ses->server->vals->cap_large_files)) {
|
|
current_read_size = min_t(uint,
|
|
current_read_size, CIFSMaxBufSize);
|
|
}
|
|
if (open_file->invalidHandle) {
|
|
rc = cifs_reopen_file(open_file, true);
|
|
if (rc != 0)
|
|
break;
|
|
}
|
|
io_parms.pid = pid;
|
|
io_parms.tcon = tcon;
|
|
io_parms.offset = *offset;
|
|
io_parms.length = current_read_size;
|
|
rc = server->ops->sync_read(xid, &open_file->fid, &io_parms,
|
|
&bytes_read, &cur_offset,
|
|
&buf_type);
|
|
} while (rc == -EAGAIN);
|
|
|
|
if (rc || (bytes_read == 0)) {
|
|
if (total_read) {
|
|
break;
|
|
} else {
|
|
free_xid(xid);
|
|
return rc;
|
|
}
|
|
} else {
|
|
cifs_stats_bytes_read(tcon, total_read);
|
|
*offset += bytes_read;
|
|
}
|
|
}
|
|
free_xid(xid);
|
|
return total_read;
|
|
}
|
|
|
|
/*
|
|
* If the page is mmap'ed into a process' page tables, then we need to make
|
|
* sure that it doesn't change while being written back.
|
|
*/
|
|
static int
|
|
cifs_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
|
|
{
|
|
struct page *page = vmf->page;
|
|
|
|
lock_page(page);
|
|
return VM_FAULT_LOCKED;
|
|
}
|
|
|
|
static struct vm_operations_struct cifs_file_vm_ops = {
|
|
.fault = filemap_fault,
|
|
.map_pages = filemap_map_pages,
|
|
.page_mkwrite = cifs_page_mkwrite,
|
|
.remap_pages = generic_file_remap_pages,
|
|
};
|
|
|
|
int cifs_file_strict_mmap(struct file *file, struct vm_area_struct *vma)
|
|
{
|
|
int rc, xid;
|
|
struct inode *inode = file_inode(file);
|
|
|
|
xid = get_xid();
|
|
|
|
if (!CIFS_CACHE_READ(CIFS_I(inode))) {
|
|
rc = cifs_zap_mapping(inode);
|
|
if (rc)
|
|
return rc;
|
|
}
|
|
|
|
rc = generic_file_mmap(file, vma);
|
|
if (rc == 0)
|
|
vma->vm_ops = &cifs_file_vm_ops;
|
|
free_xid(xid);
|
|
return rc;
|
|
}
|
|
|
|
int cifs_file_mmap(struct file *file, struct vm_area_struct *vma)
|
|
{
|
|
int rc, xid;
|
|
|
|
xid = get_xid();
|
|
rc = cifs_revalidate_file(file);
|
|
if (rc) {
|
|
cifs_dbg(FYI, "Validation prior to mmap failed, error=%d\n",
|
|
rc);
|
|
free_xid(xid);
|
|
return rc;
|
|
}
|
|
rc = generic_file_mmap(file, vma);
|
|
if (rc == 0)
|
|
vma->vm_ops = &cifs_file_vm_ops;
|
|
free_xid(xid);
|
|
return rc;
|
|
}
|
|
|
|
static void
|
|
cifs_readv_complete(struct work_struct *work)
|
|
{
|
|
unsigned int i, got_bytes;
|
|
struct cifs_readdata *rdata = container_of(work,
|
|
struct cifs_readdata, work);
|
|
|
|
got_bytes = rdata->got_bytes;
|
|
for (i = 0; i < rdata->nr_pages; i++) {
|
|
struct page *page = rdata->pages[i];
|
|
|
|
lru_cache_add_file(page);
|
|
|
|
if (rdata->result == 0 ||
|
|
(rdata->result == -EAGAIN && got_bytes)) {
|
|
flush_dcache_page(page);
|
|
SetPageUptodate(page);
|
|
}
|
|
|
|
unlock_page(page);
|
|
|
|
if (rdata->result == 0 ||
|
|
(rdata->result == -EAGAIN && got_bytes))
|
|
cifs_readpage_to_fscache(rdata->mapping->host, page);
|
|
|
|
got_bytes -= min_t(unsigned int, PAGE_CACHE_SIZE, got_bytes);
|
|
|
|
page_cache_release(page);
|
|
rdata->pages[i] = NULL;
|
|
}
|
|
kref_put(&rdata->refcount, cifs_readdata_release);
|
|
}
|
|
|
|
static int
|
|
cifs_readpages_read_into_pages(struct TCP_Server_Info *server,
|
|
struct cifs_readdata *rdata, unsigned int len)
|
|
{
|
|
int result = 0;
|
|
unsigned int i;
|
|
u64 eof;
|
|
pgoff_t eof_index;
|
|
unsigned int nr_pages = rdata->nr_pages;
|
|
struct kvec iov;
|
|
|
|
/* determine the eof that the server (probably) has */
|
|
eof = CIFS_I(rdata->mapping->host)->server_eof;
|
|
eof_index = eof ? (eof - 1) >> PAGE_CACHE_SHIFT : 0;
|
|
cifs_dbg(FYI, "eof=%llu eof_index=%lu\n", eof, eof_index);
|
|
|
|
rdata->got_bytes = 0;
|
|
rdata->tailsz = PAGE_CACHE_SIZE;
|
|
for (i = 0; i < nr_pages; i++) {
|
|
struct page *page = rdata->pages[i];
|
|
|
|
if (len >= PAGE_CACHE_SIZE) {
|
|
/* enough data to fill the page */
|
|
iov.iov_base = kmap(page);
|
|
iov.iov_len = PAGE_CACHE_SIZE;
|
|
cifs_dbg(FYI, "%u: idx=%lu iov_base=%p iov_len=%zu\n",
|
|
i, page->index, iov.iov_base, iov.iov_len);
|
|
len -= PAGE_CACHE_SIZE;
|
|
} else if (len > 0) {
|
|
/* enough for partial page, fill and zero the rest */
|
|
iov.iov_base = kmap(page);
|
|
iov.iov_len = len;
|
|
cifs_dbg(FYI, "%u: idx=%lu iov_base=%p iov_len=%zu\n",
|
|
i, page->index, iov.iov_base, iov.iov_len);
|
|
memset(iov.iov_base + len,
|
|
'\0', PAGE_CACHE_SIZE - len);
|
|
rdata->tailsz = len;
|
|
len = 0;
|
|
} else if (page->index > eof_index) {
|
|
/*
|
|
* The VFS will not try to do readahead past the
|
|
* i_size, but it's possible that we have outstanding
|
|
* writes with gaps in the middle and the i_size hasn't
|
|
* caught up yet. Populate those with zeroed out pages
|
|
* to prevent the VFS from repeatedly attempting to
|
|
* fill them until the writes are flushed.
|
|
*/
|
|
zero_user(page, 0, PAGE_CACHE_SIZE);
|
|
lru_cache_add_file(page);
|
|
flush_dcache_page(page);
|
|
SetPageUptodate(page);
|
|
unlock_page(page);
|
|
page_cache_release(page);
|
|
rdata->pages[i] = NULL;
|
|
rdata->nr_pages--;
|
|
continue;
|
|
} else {
|
|
/* no need to hold page hostage */
|
|
lru_cache_add_file(page);
|
|
unlock_page(page);
|
|
page_cache_release(page);
|
|
rdata->pages[i] = NULL;
|
|
rdata->nr_pages--;
|
|
continue;
|
|
}
|
|
|
|
result = cifs_readv_from_socket(server, &iov, 1, iov.iov_len);
|
|
kunmap(page);
|
|
if (result < 0)
|
|
break;
|
|
|
|
rdata->got_bytes += result;
|
|
}
|
|
|
|
return rdata->got_bytes > 0 && result != -ECONNABORTED ?
|
|
rdata->got_bytes : result;
|
|
}
|
|
|
|
static int
|
|
readpages_get_pages(struct address_space *mapping, struct list_head *page_list,
|
|
unsigned int rsize, struct list_head *tmplist,
|
|
unsigned int *nr_pages, loff_t *offset, unsigned int *bytes)
|
|
{
|
|
struct page *page, *tpage;
|
|
unsigned int expected_index;
|
|
int rc;
|
|
|
|
INIT_LIST_HEAD(tmplist);
|
|
|
|
page = list_entry(page_list->prev, struct page, lru);
|
|
|
|
/*
|
|
* Lock the page and put it in the cache. Since no one else
|
|
* should have access to this page, we're safe to simply set
|
|
* PG_locked without checking it first.
|
|
*/
|
|
__set_page_locked(page);
|
|
rc = add_to_page_cache_locked(page, mapping,
|
|
page->index, GFP_KERNEL);
|
|
|
|
/* give up if we can't stick it in the cache */
|
|
if (rc) {
|
|
__clear_page_locked(page);
|
|
return rc;
|
|
}
|
|
|
|
/* move first page to the tmplist */
|
|
*offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
|
|
*bytes = PAGE_CACHE_SIZE;
|
|
*nr_pages = 1;
|
|
list_move_tail(&page->lru, tmplist);
|
|
|
|
/* now try and add more pages onto the request */
|
|
expected_index = page->index + 1;
|
|
list_for_each_entry_safe_reverse(page, tpage, page_list, lru) {
|
|
/* discontinuity ? */
|
|
if (page->index != expected_index)
|
|
break;
|
|
|
|
/* would this page push the read over the rsize? */
|
|
if (*bytes + PAGE_CACHE_SIZE > rsize)
|
|
break;
|
|
|
|
__set_page_locked(page);
|
|
if (add_to_page_cache_locked(page, mapping, page->index,
|
|
GFP_KERNEL)) {
|
|
__clear_page_locked(page);
|
|
break;
|
|
}
|
|
list_move_tail(&page->lru, tmplist);
|
|
(*bytes) += PAGE_CACHE_SIZE;
|
|
expected_index++;
|
|
(*nr_pages)++;
|
|
}
|
|
return rc;
|
|
}
|
|
|
|
static int cifs_readpages(struct file *file, struct address_space *mapping,
|
|
struct list_head *page_list, unsigned num_pages)
|
|
{
|
|
int rc;
|
|
struct list_head tmplist;
|
|
struct cifsFileInfo *open_file = file->private_data;
|
|
struct cifs_sb_info *cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
|
|
struct TCP_Server_Info *server;
|
|
pid_t pid;
|
|
|
|
/*
|
|
* Reads as many pages as possible from fscache. Returns -ENOBUFS
|
|
* immediately if the cookie is negative
|
|
*
|
|
* After this point, every page in the list might have PG_fscache set,
|
|
* so we will need to clean that up off of every page we don't use.
|
|
*/
|
|
rc = cifs_readpages_from_fscache(mapping->host, mapping, page_list,
|
|
&num_pages);
|
|
if (rc == 0)
|
|
return rc;
|
|
|
|
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
|
|
pid = open_file->pid;
|
|
else
|
|
pid = current->tgid;
|
|
|
|
rc = 0;
|
|
server = tlink_tcon(open_file->tlink)->ses->server;
|
|
|
|
cifs_dbg(FYI, "%s: file=%p mapping=%p num_pages=%u\n",
|
|
__func__, file, mapping, num_pages);
|
|
|
|
/*
|
|
* Start with the page at end of list and move it to private
|
|
* list. Do the same with any following pages until we hit
|
|
* the rsize limit, hit an index discontinuity, or run out of
|
|
* pages. Issue the async read and then start the loop again
|
|
* until the list is empty.
|
|
*
|
|
* Note that list order is important. The page_list is in
|
|
* the order of declining indexes. When we put the pages in
|
|
* the rdata->pages, then we want them in increasing order.
|
|
*/
|
|
while (!list_empty(page_list)) {
|
|
unsigned int i, nr_pages, bytes, rsize;
|
|
loff_t offset;
|
|
struct page *page, *tpage;
|
|
struct cifs_readdata *rdata;
|
|
unsigned credits;
|
|
|
|
rc = server->ops->wait_mtu_credits(server, cifs_sb->rsize,
|
|
&rsize, &credits);
|
|
if (rc)
|
|
break;
|
|
|
|
/*
|
|
* Give up immediately if rsize is too small to read an entire
|
|
* page. The VFS will fall back to readpage. We should never
|
|
* reach this point however since we set ra_pages to 0 when the
|
|
* rsize is smaller than a cache page.
|
|
*/
|
|
if (unlikely(rsize < PAGE_CACHE_SIZE)) {
|
|
add_credits_and_wake_if(server, credits, 0);
|
|
return 0;
|
|
}
|
|
|
|
rc = readpages_get_pages(mapping, page_list, rsize, &tmplist,
|
|
&nr_pages, &offset, &bytes);
|
|
if (rc) {
|
|
add_credits_and_wake_if(server, credits, 0);
|
|
break;
|
|
}
|
|
|
|
rdata = cifs_readdata_alloc(nr_pages, cifs_readv_complete);
|
|
if (!rdata) {
|
|
/* best to give up if we're out of mem */
|
|
list_for_each_entry_safe(page, tpage, &tmplist, lru) {
|
|
list_del(&page->lru);
|
|
lru_cache_add_file(page);
|
|
unlock_page(page);
|
|
page_cache_release(page);
|
|
}
|
|
rc = -ENOMEM;
|
|
add_credits_and_wake_if(server, credits, 0);
|
|
break;
|
|
}
|
|
|
|
rdata->cfile = cifsFileInfo_get(open_file);
|
|
rdata->mapping = mapping;
|
|
rdata->offset = offset;
|
|
rdata->bytes = bytes;
|
|
rdata->pid = pid;
|
|
rdata->pagesz = PAGE_CACHE_SIZE;
|
|
rdata->read_into_pages = cifs_readpages_read_into_pages;
|
|
rdata->credits = credits;
|
|
|
|
list_for_each_entry_safe(page, tpage, &tmplist, lru) {
|
|
list_del(&page->lru);
|
|
rdata->pages[rdata->nr_pages++] = page;
|
|
}
|
|
|
|
if (!rdata->cfile->invalidHandle ||
|
|
!cifs_reopen_file(rdata->cfile, true))
|
|
rc = server->ops->async_readv(rdata);
|
|
if (rc) {
|
|
add_credits_and_wake_if(server, rdata->credits, 0);
|
|
for (i = 0; i < rdata->nr_pages; i++) {
|
|
page = rdata->pages[i];
|
|
lru_cache_add_file(page);
|
|
unlock_page(page);
|
|
page_cache_release(page);
|
|
}
|
|
/* Fallback to the readpage in error/reconnect cases */
|
|
kref_put(&rdata->refcount, cifs_readdata_release);
|
|
break;
|
|
}
|
|
|
|
kref_put(&rdata->refcount, cifs_readdata_release);
|
|
}
|
|
|
|
/* Any pages that have been shown to fscache but didn't get added to
|
|
* the pagecache must be uncached before they get returned to the
|
|
* allocator.
|
|
*/
|
|
cifs_fscache_readpages_cancel(mapping->host, page_list);
|
|
return rc;
|
|
}
|
|
|
|
/*
|
|
* cifs_readpage_worker must be called with the page pinned
|
|
*/
|
|
static int cifs_readpage_worker(struct file *file, struct page *page,
|
|
loff_t *poffset)
|
|
{
|
|
char *read_data;
|
|
int rc;
|
|
|
|
/* Is the page cached? */
|
|
rc = cifs_readpage_from_fscache(file_inode(file), page);
|
|
if (rc == 0)
|
|
goto read_complete;
|
|
|
|
read_data = kmap(page);
|
|
/* for reads over a certain size could initiate async read ahead */
|
|
|
|
rc = cifs_read(file, read_data, PAGE_CACHE_SIZE, poffset);
|
|
|
|
if (rc < 0)
|
|
goto io_error;
|
|
else
|
|
cifs_dbg(FYI, "Bytes read %d\n", rc);
|
|
|
|
file_inode(file)->i_atime =
|
|
current_fs_time(file_inode(file)->i_sb);
|
|
|
|
if (PAGE_CACHE_SIZE > rc)
|
|
memset(read_data + rc, 0, PAGE_CACHE_SIZE - rc);
|
|
|
|
flush_dcache_page(page);
|
|
SetPageUptodate(page);
|
|
|
|
/* send this page to the cache */
|
|
cifs_readpage_to_fscache(file_inode(file), page);
|
|
|
|
rc = 0;
|
|
|
|
io_error:
|
|
kunmap(page);
|
|
unlock_page(page);
|
|
|
|
read_complete:
|
|
return rc;
|
|
}
|
|
|
|
static int cifs_readpage(struct file *file, struct page *page)
|
|
{
|
|
loff_t offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
|
|
int rc = -EACCES;
|
|
unsigned int xid;
|
|
|
|
xid = get_xid();
|
|
|
|
if (file->private_data == NULL) {
|
|
rc = -EBADF;
|
|
free_xid(xid);
|
|
return rc;
|
|
}
|
|
|
|
cifs_dbg(FYI, "readpage %p at offset %d 0x%x\n",
|
|
page, (int)offset, (int)offset);
|
|
|
|
rc = cifs_readpage_worker(file, page, &offset);
|
|
|
|
free_xid(xid);
|
|
return rc;
|
|
}
|
|
|
|
static int is_inode_writable(struct cifsInodeInfo *cifs_inode)
|
|
{
|
|
struct cifsFileInfo *open_file;
|
|
|
|
spin_lock(&cifs_file_list_lock);
|
|
list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
|
|
if (OPEN_FMODE(open_file->f_flags) & FMODE_WRITE) {
|
|
spin_unlock(&cifs_file_list_lock);
|
|
return 1;
|
|
}
|
|
}
|
|
spin_unlock(&cifs_file_list_lock);
|
|
return 0;
|
|
}
|
|
|
|
/* We do not want to update the file size from server for inodes
|
|
open for write - to avoid races with writepage extending
|
|
the file - in the future we could consider allowing
|
|
refreshing the inode only on increases in the file size
|
|
but this is tricky to do without racing with writebehind
|
|
page caching in the current Linux kernel design */
|
|
bool is_size_safe_to_change(struct cifsInodeInfo *cifsInode, __u64 end_of_file)
|
|
{
|
|
if (!cifsInode)
|
|
return true;
|
|
|
|
if (is_inode_writable(cifsInode)) {
|
|
/* This inode is open for write at least once */
|
|
struct cifs_sb_info *cifs_sb;
|
|
|
|
cifs_sb = CIFS_SB(cifsInode->vfs_inode.i_sb);
|
|
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DIRECT_IO) {
|
|
/* since no page cache to corrupt on directio
|
|
we can change size safely */
|
|
return true;
|
|
}
|
|
|
|
if (i_size_read(&cifsInode->vfs_inode) < end_of_file)
|
|
return true;
|
|
|
|
return false;
|
|
} else
|
|
return true;
|
|
}
|
|
|
|
static int cifs_write_begin(struct file *file, struct address_space *mapping,
|
|
loff_t pos, unsigned len, unsigned flags,
|
|
struct page **pagep, void **fsdata)
|
|
{
|
|
int oncethru = 0;
|
|
pgoff_t index = pos >> PAGE_CACHE_SHIFT;
|
|
loff_t offset = pos & (PAGE_CACHE_SIZE - 1);
|
|
loff_t page_start = pos & PAGE_MASK;
|
|
loff_t i_size;
|
|
struct page *page;
|
|
int rc = 0;
|
|
|
|
cifs_dbg(FYI, "write_begin from %lld len %d\n", (long long)pos, len);
|
|
|
|
start:
|
|
page = grab_cache_page_write_begin(mapping, index, flags);
|
|
if (!page) {
|
|
rc = -ENOMEM;
|
|
goto out;
|
|
}
|
|
|
|
if (PageUptodate(page))
|
|
goto out;
|
|
|
|
/*
|
|
* If we write a full page it will be up to date, no need to read from
|
|
* the server. If the write is short, we'll end up doing a sync write
|
|
* instead.
|
|
*/
|
|
if (len == PAGE_CACHE_SIZE)
|
|
goto out;
|
|
|
|
/*
|
|
* optimize away the read when we have an oplock, and we're not
|
|
* expecting to use any of the data we'd be reading in. That
|
|
* is, when the page lies beyond the EOF, or straddles the EOF
|
|
* and the write will cover all of the existing data.
|
|
*/
|
|
if (CIFS_CACHE_READ(CIFS_I(mapping->host))) {
|
|
i_size = i_size_read(mapping->host);
|
|
if (page_start >= i_size ||
|
|
(offset == 0 && (pos + len) >= i_size)) {
|
|
zero_user_segments(page, 0, offset,
|
|
offset + len,
|
|
PAGE_CACHE_SIZE);
|
|
/*
|
|
* PageChecked means that the parts of the page
|
|
* to which we're not writing are considered up
|
|
* to date. Once the data is copied to the
|
|
* page, it can be set uptodate.
|
|
*/
|
|
SetPageChecked(page);
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
if ((file->f_flags & O_ACCMODE) != O_WRONLY && !oncethru) {
|
|
/*
|
|
* might as well read a page, it is fast enough. If we get
|
|
* an error, we don't need to return it. cifs_write_end will
|
|
* do a sync write instead since PG_uptodate isn't set.
|
|
*/
|
|
cifs_readpage_worker(file, page, &page_start);
|
|
page_cache_release(page);
|
|
oncethru = 1;
|
|
goto start;
|
|
} else {
|
|
/* we could try using another file handle if there is one -
|
|
but how would we lock it to prevent close of that handle
|
|
racing with this read? In any case
|
|
this will be written out by write_end so is fine */
|
|
}
|
|
out:
|
|
*pagep = page;
|
|
return rc;
|
|
}
|
|
|
|
static int cifs_release_page(struct page *page, gfp_t gfp)
|
|
{
|
|
if (PagePrivate(page))
|
|
return 0;
|
|
|
|
return cifs_fscache_release_page(page, gfp);
|
|
}
|
|
|
|
static void cifs_invalidate_page(struct page *page, unsigned int offset,
|
|
unsigned int length)
|
|
{
|
|
struct cifsInodeInfo *cifsi = CIFS_I(page->mapping->host);
|
|
|
|
if (offset == 0 && length == PAGE_CACHE_SIZE)
|
|
cifs_fscache_invalidate_page(page, &cifsi->vfs_inode);
|
|
}
|
|
|
|
static int cifs_launder_page(struct page *page)
|
|
{
|
|
int rc = 0;
|
|
loff_t range_start = page_offset(page);
|
|
loff_t range_end = range_start + (loff_t)(PAGE_CACHE_SIZE - 1);
|
|
struct writeback_control wbc = {
|
|
.sync_mode = WB_SYNC_ALL,
|
|
.nr_to_write = 0,
|
|
.range_start = range_start,
|
|
.range_end = range_end,
|
|
};
|
|
|
|
cifs_dbg(FYI, "Launder page: %p\n", page);
|
|
|
|
if (clear_page_dirty_for_io(page))
|
|
rc = cifs_writepage_locked(page, &wbc);
|
|
|
|
cifs_fscache_invalidate_page(page, page->mapping->host);
|
|
return rc;
|
|
}
|
|
|
|
void cifs_oplock_break(struct work_struct *work)
|
|
{
|
|
struct cifsFileInfo *cfile = container_of(work, struct cifsFileInfo,
|
|
oplock_break);
|
|
struct inode *inode = cfile->dentry->d_inode;
|
|
struct cifsInodeInfo *cinode = CIFS_I(inode);
|
|
struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
|
|
struct TCP_Server_Info *server = tcon->ses->server;
|
|
int rc = 0;
|
|
|
|
wait_on_bit(&cinode->flags, CIFS_INODE_PENDING_WRITERS,
|
|
TASK_UNINTERRUPTIBLE);
|
|
|
|
server->ops->downgrade_oplock(server, cinode,
|
|
test_bit(CIFS_INODE_DOWNGRADE_OPLOCK_TO_L2, &cinode->flags));
|
|
|
|
if (!CIFS_CACHE_WRITE(cinode) && CIFS_CACHE_READ(cinode) &&
|
|
cifs_has_mand_locks(cinode)) {
|
|
cifs_dbg(FYI, "Reset oplock to None for inode=%p due to mand locks\n",
|
|
inode);
|
|
cinode->oplock = 0;
|
|
}
|
|
|
|
if (inode && S_ISREG(inode->i_mode)) {
|
|
if (CIFS_CACHE_READ(cinode))
|
|
break_lease(inode, O_RDONLY);
|
|
else
|
|
break_lease(inode, O_WRONLY);
|
|
rc = filemap_fdatawrite(inode->i_mapping);
|
|
if (!CIFS_CACHE_READ(cinode)) {
|
|
rc = filemap_fdatawait(inode->i_mapping);
|
|
mapping_set_error(inode->i_mapping, rc);
|
|
cifs_zap_mapping(inode);
|
|
}
|
|
cifs_dbg(FYI, "Oplock flush inode %p rc %d\n", inode, rc);
|
|
}
|
|
|
|
rc = cifs_push_locks(cfile);
|
|
if (rc)
|
|
cifs_dbg(VFS, "Push locks rc = %d\n", rc);
|
|
|
|
/*
|
|
* releasing stale oplock after recent reconnect of smb session using
|
|
* a now incorrect file handle is not a data integrity issue but do
|
|
* not bother sending an oplock release if session to server still is
|
|
* disconnected since oplock already released by the server
|
|
*/
|
|
if (!cfile->oplock_break_cancelled) {
|
|
rc = tcon->ses->server->ops->oplock_response(tcon, &cfile->fid,
|
|
cinode);
|
|
cifs_dbg(FYI, "Oplock release rc = %d\n", rc);
|
|
}
|
|
cifs_done_oplock_break(cinode);
|
|
}
|
|
|
|
/*
|
|
* The presence of cifs_direct_io() in the address space ops vector
|
|
* allowes open() O_DIRECT flags which would have failed otherwise.
|
|
*
|
|
* In the non-cached mode (mount with cache=none), we shunt off direct read and write requests
|
|
* so this method should never be called.
|
|
*
|
|
* Direct IO is not yet supported in the cached mode.
|
|
*/
|
|
static ssize_t
|
|
cifs_direct_io(int rw, struct kiocb *iocb, struct iov_iter *iter,
|
|
loff_t pos)
|
|
{
|
|
/*
|
|
* FIXME
|
|
* Eventually need to support direct IO for non forcedirectio mounts
|
|
*/
|
|
return -EINVAL;
|
|
}
|
|
|
|
|
|
const struct address_space_operations cifs_addr_ops = {
|
|
.readpage = cifs_readpage,
|
|
.readpages = cifs_readpages,
|
|
.writepage = cifs_writepage,
|
|
.writepages = cifs_writepages,
|
|
.write_begin = cifs_write_begin,
|
|
.write_end = cifs_write_end,
|
|
.set_page_dirty = __set_page_dirty_nobuffers,
|
|
.releasepage = cifs_release_page,
|
|
.direct_IO = cifs_direct_io,
|
|
.invalidatepage = cifs_invalidate_page,
|
|
.launder_page = cifs_launder_page,
|
|
};
|
|
|
|
/*
|
|
* cifs_readpages requires the server to support a buffer large enough to
|
|
* contain the header plus one complete page of data. Otherwise, we need
|
|
* to leave cifs_readpages out of the address space operations.
|
|
*/
|
|
const struct address_space_operations cifs_addr_ops_smallbuf = {
|
|
.readpage = cifs_readpage,
|
|
.writepage = cifs_writepage,
|
|
.writepages = cifs_writepages,
|
|
.write_begin = cifs_write_begin,
|
|
.write_end = cifs_write_end,
|
|
.set_page_dirty = __set_page_dirty_nobuffers,
|
|
.releasepage = cifs_release_page,
|
|
.invalidatepage = cifs_invalidate_page,
|
|
.launder_page = cifs_launder_page,
|
|
};
|