diff options
| -rw-r--r-- | fs/cifs/cifsglob.h | 2 | ||||
| -rw-r--r-- | fs/cifs/file.c | 206 |
2 files changed, 197 insertions, 11 deletions
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h index d153d0b89d3..8238aa13e01 100644 --- a/fs/cifs/cifsglob.h +++ b/fs/cifs/cifsglob.h @@ -496,6 +496,8 @@ extern struct cifs_tcon *cifs_sb_master_tcon(struct cifs_sb_info *cifs_sb); */ struct cifsLockInfo { struct list_head llist; /* pointer to next cifsLockInfo */ + struct list_head blist; /* pointer to locks blocked on this */ + wait_queue_head_t block_q; __u64 offset; __u64 length; __u32 pid; diff --git a/fs/cifs/file.c b/fs/cifs/file.c index a3b545ff525..34cbbee30b1 100644 --- a/fs/cifs/file.c +++ b/fs/cifs/file.c @@ -275,11 +275,14 @@ cifs_new_fileinfo(__u16 fileHandle, struct file *file, spin_unlock(&cifs_file_list_lock); cifs_set_oplock_level(pCifsInode, oplock); + pCifsInode->can_cache_brlcks = pCifsInode->clientCanCacheAll; file->private_data = pCifsFile; return pCifsFile; } +static void cifs_del_lock_waiters(struct cifsLockInfo *lock); + /* * Release a reference on the file private data. This may involve closing * the filehandle out on the server. Must be called without holding @@ -335,6 +338,7 @@ void cifsFileInfo_put(struct cifsFileInfo *cifs_file) if (li->netfid != cifs_file->netfid) continue; list_del(&li->llist); + cifs_del_lock_waiters(li); kfree(li); } mutex_unlock(&cifsi->lock_mutex); @@ -640,24 +644,182 @@ int cifs_closedir(struct inode *inode, struct file *file) return rc; } -static int store_file_lock(struct cifsInodeInfo *cinode, __u64 len, - __u64 offset, __u8 type, __u16 netfid) +static struct cifsLockInfo * +cifs_lock_init(__u64 len, __u64 offset, __u8 type, __u16 netfid) { struct cifsLockInfo *li = kmalloc(sizeof(struct cifsLockInfo), GFP_KERNEL); - if (li == NULL) - return -ENOMEM; + if (!li) + return li; li->netfid = netfid; li->offset = offset; li->length = len; li->type = type; li->pid = current->tgid; + INIT_LIST_HEAD(&li->blist); + init_waitqueue_head(&li->block_q); + return li; +} + +static 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); + } +} + +static bool +cifs_find_lock_conflict(struct cifsInodeInfo *cinode, __u64 offset, + __u64 length, __u8 type, __u16 netfid, + struct cifsLockInfo **conf_lock) +{ + struct cifsLockInfo *li, *tmp; + + list_for_each_entry_safe(li, tmp, &cinode->llist, llist) { + if (offset + length <= li->offset || + offset >= li->offset + li->length) + continue; + else if ((type & LOCKING_ANDX_SHARED_LOCK) && + ((netfid == li->netfid && current->tgid == li->pid) || + type == li->type)) + continue; + else { + *conf_lock = li; + return true; + } + } + return false; +} + +static int +cifs_lock_test(struct cifsInodeInfo *cinode, __u64 offset, __u64 length, + __u8 type, __u16 netfid, struct file_lock *flock) +{ + int rc = 0; + struct cifsLockInfo *conf_lock; + bool exist; + + mutex_lock(&cinode->lock_mutex); + + exist = cifs_find_lock_conflict(cinode, offset, length, type, netfid, + &conf_lock); + 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 & LOCKING_ANDX_SHARED_LOCK) + 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; + + mutex_unlock(&cinode->lock_mutex); + return rc; +} + +static int +cifs_lock_add(struct cifsInodeInfo *cinode, __u64 len, __u64 offset, + __u8 type, __u16 netfid) +{ + struct cifsLockInfo *li; + + li = cifs_lock_init(len, offset, type, netfid); + if (!li) + return -ENOMEM; + mutex_lock(&cinode->lock_mutex); list_add_tail(&li->llist, &cinode->llist); mutex_unlock(&cinode->lock_mutex); return 0; } +static int +cifs_lock_add_if(struct cifsInodeInfo *cinode, __u64 offset, __u64 length, + __u8 type, __u16 netfid, bool wait) +{ + struct cifsLockInfo *lock, *conf_lock; + bool exist; + int rc = 0; + + lock = cifs_lock_init(length, offset, type, netfid); + if (!lock) + return -ENOMEM; + +try_again: + exist = false; + mutex_lock(&cinode->lock_mutex); + + exist = cifs_find_lock_conflict(cinode, offset, length, type, netfid, + &conf_lock); + if (!exist && cinode->can_cache_brlcks) { + list_add_tail(&lock->llist, &cinode->llist); + mutex_unlock(&cinode->lock_mutex); + return rc; + } + + if (!exist) + rc = 1; + else if (!wait) + rc = -EACCES; + else { + list_add_tail(&lock->blist, &conf_lock->blist); + mutex_unlock(&cinode->lock_mutex); + rc = wait_event_interruptible(lock->block_q, + (lock->blist.prev == &lock->blist) && + (lock->blist.next == &lock->blist)); + if (!rc) + goto try_again; + else { + mutex_lock(&cinode->lock_mutex); + list_del_init(&lock->blist); + mutex_unlock(&cinode->lock_mutex); + } + } + + kfree(lock); + mutex_unlock(&cinode->lock_mutex); + return rc; +} + +static int +cifs_push_locks(struct cifsFileInfo *cfile) +{ + int xid, rc = 0, stored_rc; + struct cifsLockInfo *li, *tmp; + struct cifs_tcon *tcon; + struct cifsInodeInfo *cinode = CIFS_I(cfile->dentry->d_inode); + + xid = GetXid(); + tcon = tlink_tcon(cfile->tlink); + + mutex_lock(&cinode->lock_mutex); + if (!cinode->can_cache_brlcks) { + mutex_unlock(&cinode->lock_mutex); + FreeXid(xid); + return rc; + } + + list_for_each_entry_safe(li, tmp, &cinode->llist, llist) { + stored_rc = CIFSSMBLock(xid, tcon, cfile->netfid, + li->pid, li->length, li->offset, + 0, 1, li->type, 0, 0); + if (stored_rc) + rc = stored_rc; + } + + cinode->can_cache_brlcks = false; + mutex_unlock(&cinode->lock_mutex); + + FreeXid(xid); + return rc; +} + static void cifs_read_flock(struct file_lock *flock, __u8 *type, int *lock, int *unlock, bool *wait_flag) @@ -708,6 +870,7 @@ cifs_getlk(struct cifsFileInfo *cfile, struct file_lock *flock, __u8 type, { int rc = 0; __u64 length = 1 + flock->fl_end - flock->fl_start; + struct cifsInodeInfo *cinode = CIFS_I(cfile->dentry->d_inode); __u16 netfid = cfile->netfid; struct cifs_tcon *tcon = tlink_tcon(cfile->tlink); @@ -723,6 +886,11 @@ cifs_getlk(struct cifsFileInfo *cfile, struct file_lock *flock, __u8 type, return rc; } + rc = cifs_lock_test(cinode, flock->fl_start, length, type, netfid, + flock); + if (!rc) + return rc; + /* BB we could chain these into one lock request BB */ rc = CIFSSMBLock(xid, tcon, netfid, current->tgid, length, flock->fl_start, 0, 1, type, 0, 0); @@ -790,12 +958,19 @@ cifs_setlk(struct file *file, struct file_lock *flock, __u8 type, } if (lock) { + rc = cifs_lock_add_if(cinode, flock->fl_start, length, + type, netfid, wait_flag); + if (rc < 0) + return rc; + else if (!rc) + goto out; + rc = CIFSSMBLock(xid, tcon, netfid, current->tgid, length, - flock->fl_start, 0, lock, type, wait_flag, 0); + flock->fl_start, 0, 1, type, wait_flag, 0); if (rc == 0) { /* For Windows locks we must store them. */ - rc = store_file_lock(cinode, length, flock->fl_start, - type, netfid); + rc = cifs_lock_add(cinode, length, flock->fl_start, + type, netfid); } } else if (unlock) { /* @@ -816,14 +991,19 @@ cifs_setlk(struct file *file, struct file_lock *flock, __u8 type, if (cfile->netfid != li->netfid) continue; - stored_rc = CIFSSMBLock(xid, tcon, netfid, - current->tgid, li->length, - li->offset, 1, 0, li->type, - 0, 0); + if (!cinode->can_cache_brlcks) + stored_rc = CIFSSMBLock(xid, tcon, netfid, + current->tgid, + li->length, li->offset, + 1, 0, li->type, 0, 0); + else + stored_rc = 0; + if (stored_rc) rc = stored_rc; else { list_del(&li->llist); + cifs_del_lock_waiters(li); kfree(li); } } @@ -2404,6 +2584,10 @@ void cifs_oplock_break(struct work_struct *work) cFYI(1, "Oplock flush inode %p rc %d", inode, rc); } + rc = cifs_push_locks(cfile); + if (rc) + cERROR(1, "Push locks rc = %d", rc); + /* * releasing stale oplock after recent reconnect of smb session using * a now incorrect file handle is not a data integrity issue but do |