From 4f6bcec910d45e4f46b1514977caa529bc69e645 Mon Sep 17 00:00:00 2001 From: Pavel Shilovsky Date: Sat, 22 Oct 2011 15:33:30 +0400 Subject: CIFS: Implement caching mechanism for posix brlocks to handle all lock requests on the client in an exclusive oplock case. Signed-off-by: Pavel Shilovsky Acked-by: Jeff Layton Signed-off-by: Steve French --- fs/cifs/file.c | 150 +++++++++++++++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 141 insertions(+), 9 deletions(-) (limited to 'fs/cifs/file.c') diff --git a/fs/cifs/file.c b/fs/cifs/file.c index 34cbbee30b1..805e2bd1dfd 100644 --- a/fs/cifs/file.c +++ b/fs/cifs/file.c @@ -788,7 +788,42 @@ try_again: } static int -cifs_push_locks(struct cifsFileInfo *cfile) +cifs_posix_lock_test(struct file *file, struct file_lock *flock) +{ + int rc = 0; + struct cifsInodeInfo *cinode = CIFS_I(file->f_path.dentry->d_inode); + unsigned char saved_type = flock->fl_type; + + mutex_lock(&cinode->lock_mutex); + posix_test_lock(file, flock); + + if (flock->fl_type == F_UNLCK && !cinode->can_cache_brlcks) { + flock->fl_type = saved_type; + rc = 1; + } + + mutex_unlock(&cinode->lock_mutex); + return rc; +} + +static int +cifs_posix_lock_set(struct file *file, struct file_lock *flock) +{ + struct cifsInodeInfo *cinode = CIFS_I(file->f_path.dentry->d_inode); + int rc; + + mutex_lock(&cinode->lock_mutex); + if (!cinode->can_cache_brlcks) { + mutex_unlock(&cinode->lock_mutex); + return 1; + } + rc = posix_lock_file_wait(file, flock); + mutex_unlock(&cinode->lock_mutex); + return rc; +} + +static int +cifs_push_mandatory_locks(struct cifsFileInfo *cfile) { int xid, rc = 0, stored_rc; struct cifsLockInfo *li, *tmp; @@ -820,6 +855,91 @@ cifs_push_locks(struct cifsFileInfo *cfile) 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) + +static int +cifs_push_posix_locks(struct cifsFileInfo *cfile) +{ + struct cifsInodeInfo *cinode = CIFS_I(cfile->dentry->d_inode); + struct cifs_tcon *tcon = tlink_tcon(cfile->tlink); + struct file_lock *flock, **before; + struct cifsLockInfo *lck, *tmp; + int rc = 0, xid, type; + __u64 length; + struct list_head locks_to_send; + + xid = GetXid(); + + mutex_lock(&cinode->lock_mutex); + if (!cinode->can_cache_brlcks) { + mutex_unlock(&cinode->lock_mutex); + FreeXid(xid); + return rc; + } + + INIT_LIST_HEAD(&locks_to_send); + + lock_flocks(); + cifs_for_each_lock(cfile->dentry->d_inode, before) { + flock = *before; + 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 = cifs_lock_init(length, flock->fl_start, type, + cfile->netfid); + if (!lck) { + rc = -ENOMEM; + goto send_locks; + } + lck->pid = flock->fl_pid; + + list_add_tail(&lck->llist, &locks_to_send); + } + +send_locks: + unlock_flocks(); + + list_for_each_entry_safe(lck, tmp, &locks_to_send, llist) { + struct file_lock tmp_lock; + int stored_rc; + + tmp_lock.fl_start = lck->offset; + stored_rc = CIFSSMBPosixLock(xid, tcon, lck->netfid, lck->pid, + 0, lck->length, &tmp_lock, + lck->type, 0); + if (stored_rc) + rc = stored_rc; + list_del(&lck->llist); + kfree(lck); + } + + cinode->can_cache_brlcks = false; + mutex_unlock(&cinode->lock_mutex); + + FreeXid(xid); + return rc; +} + +static int +cifs_push_locks(struct cifsFileInfo *cfile) +{ + struct cifs_sb_info *cifs_sb = CIFS_SB(cfile->dentry->d_sb); + struct cifs_tcon *tcon = tlink_tcon(cfile->tlink); + + if ((tcon->ses->capabilities & CAP_UNIX) && + (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) && + ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0)) + return cifs_push_posix_locks(cfile); + + return cifs_push_mandatory_locks(cfile); +} + static void cifs_read_flock(struct file_lock *flock, __u8 *type, int *lock, int *unlock, bool *wait_flag) @@ -865,24 +985,30 @@ cifs_read_flock(struct file_lock *flock, __u8 *type, int *lock, int *unlock, } static int -cifs_getlk(struct cifsFileInfo *cfile, struct file_lock *flock, __u8 type, +cifs_getlk(struct file *file, struct file_lock *flock, __u8 type, bool wait_flag, bool posix_lck, 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 cifsInodeInfo *cinode = CIFS_I(cfile->dentry->d_inode); __u16 netfid = cfile->netfid; - struct cifs_tcon *tcon = tlink_tcon(cfile->tlink); if (posix_lck) { int posix_lock_type; + + rc = cifs_posix_lock_test(file, flock); + if (!rc) + return rc; + if (type & LOCKING_ANDX_SHARED_LOCK) posix_lock_type = CIFS_RDLCK; else posix_lock_type = CIFS_WRLCK; - rc = CIFSSMBPosixLock(xid, tcon, netfid, 1 /* get */, - length, flock, posix_lock_type, - wait_flag); + rc = CIFSSMBPosixLock(xid, tcon, netfid, current->tgid, + 1 /* get */, length, flock, + posix_lock_type, wait_flag); return rc; } @@ -944,6 +1070,11 @@ cifs_setlk(struct file *file, struct file_lock *flock, __u8 type, if (posix_lck) { int posix_lock_type; + + rc = cifs_posix_lock_set(file, flock); + if (!rc || rc < 0) + return rc; + if (type & LOCKING_ANDX_SHARED_LOCK) posix_lock_type = CIFS_RDLCK; else @@ -952,8 +1083,9 @@ cifs_setlk(struct file *file, struct file_lock *flock, __u8 type, if (unlock == 1) posix_lock_type = CIFS_UNLCK; - rc = CIFSSMBPosixLock(xid, tcon, netfid, 0 /* set */, length, - flock, posix_lock_type, wait_flag); + rc = CIFSSMBPosixLock(xid, tcon, netfid, current->tgid, + 0 /* set */, length, flock, + posix_lock_type, wait_flag); goto out; } @@ -1052,7 +1184,7 @@ int cifs_lock(struct file *file, int cmd, struct file_lock *flock) * negative length which we can not accept over the wire. */ if (IS_GETLK(cmd)) { - rc = cifs_getlk(cfile, flock, type, wait_flag, posix_lck, xid); + rc = cifs_getlk(file, flock, type, wait_flag, posix_lck, xid); FreeXid(xid); return rc; } -- cgit v1.2.3-18-g5258