CIFS: Move locks to cifsFileInfo structure
CIFS brlock cache can be used by several file handles if we have a
write-caching lease on the file that is supported by SMB2 protocol.
Prepate the code to handle this situation correctly by sorting brlocks
by a fid to easily push them in portions when lease break comes.
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 8a6928c..d6660f7 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -955,7 +955,6 @@
struct cifsInodeInfo *cifsi = inode;
inode_init_once(&cifsi->vfs_inode);
- INIT_LIST_HEAD(&cifsi->llist);
mutex_init(&cifsi->lock_mutex);
}
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index c41bf6d..03d24a5 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -568,7 +568,6 @@
__u64 length;
__u32 pid;
__u8 type;
- __u16 netfid;
};
/*
@@ -593,6 +592,10 @@
struct cifsFileInfo {
struct list_head tlist; /* pointer to next fid owned by tcon */
struct list_head flist; /* next fid (file instance) for this inode */
+ struct list_head llist; /*
+ * brlocks held by this fid, protected by
+ * lock_mutex from cifsInodeInfo structure
+ */
unsigned int uid; /* allows finding which FileInfo structure */
__u32 pid; /* process id who opened file */
__u16 netfid; /* file id from remote */
@@ -635,9 +638,12 @@
*/
struct cifsInodeInfo {
- struct list_head llist; /* brlocks for this inode */
bool can_cache_brlcks;
- struct mutex lock_mutex; /* protect two fields above */
+ struct mutex lock_mutex; /*
+ * protect the field above and llist
+ * from every cifsFileInfo structure
+ * from openFileList
+ */
/* BB add in lists for dirty pages i.e. write caching info for oplock */
struct list_head openFileList;
__u32 cifsAttrs; /* e.g. DOS archive bit, sparse, compressed, system */
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 4b5fe39..fc45cd9 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -264,6 +264,7 @@
pCifsFile->tlink = cifs_get_tlink(tlink);
mutex_init(&pCifsFile->fh_mutex);
INIT_WORK(&pCifsFile->oplock_break, cifs_oplock_break);
+ INIT_LIST_HEAD(&pCifsFile->llist);
spin_lock(&cifs_file_list_lock);
list_add(&pCifsFile->tlist, &(tlink_tcon(tlink)->openFileList));
@@ -334,9 +335,7 @@
* is closed anyway.
*/
mutex_lock(&cifsi->lock_mutex);
- list_for_each_entry_safe(li, tmp, &cifsi->llist, llist) {
- if (li->netfid != cifs_file->netfid)
- continue;
+ list_for_each_entry_safe(li, tmp, &cifs_file->llist, llist) {
list_del(&li->llist);
cifs_del_lock_waiters(li);
kfree(li);
@@ -645,7 +644,7 @@
}
static struct cifsLockInfo *
-cifs_lock_init(__u64 offset, __u64 length, __u8 type, __u16 netfid)
+cifs_lock_init(__u64 offset, __u64 length, __u8 type)
{
struct cifsLockInfo *lock =
kmalloc(sizeof(struct cifsLockInfo), GFP_KERNEL);
@@ -654,7 +653,6 @@
lock->offset = offset;
lock->length = length;
lock->type = type;
- lock->netfid = netfid;
lock->pid = current->tgid;
INIT_LIST_HEAD(&lock->blist);
init_waitqueue_head(&lock->block_q);
@@ -672,19 +670,19 @@
}
static bool
-__cifs_find_lock_conflict(struct cifsInodeInfo *cinode, __u64 offset,
- __u64 length, __u8 type, __u16 netfid,
- struct cifsLockInfo **conf_lock)
+cifs_find_fid_lock_conflict(struct cifsFileInfo *cfile, __u64 offset,
+ __u64 length, __u8 type, __u16 netfid,
+ struct cifsLockInfo **conf_lock)
{
- struct cifsLockInfo *li, *tmp;
+ struct cifsLockInfo *li;
- list_for_each_entry_safe(li, tmp, &cinode->llist, llist) {
+ list_for_each_entry(li, &cfile->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))
+ ((netfid == cfile->netfid && current->tgid == li->pid)
+ || type == li->type))
continue;
else {
*conf_lock = li;
@@ -695,11 +693,23 @@
}
static bool
-cifs_find_lock_conflict(struct cifsInodeInfo *cinode, struct cifsLockInfo *lock,
+cifs_find_lock_conflict(struct cifsInodeInfo *cinode, __u64 offset,
+ __u64 length, __u8 type, __u16 netfid,
struct cifsLockInfo **conf_lock)
{
- return __cifs_find_lock_conflict(cinode, lock->offset, lock->length,
- lock->type, lock->netfid, conf_lock);
+ bool rc = false;
+ struct cifsFileInfo *fid, *tmp;
+
+ spin_lock(&cifs_file_list_lock);
+ list_for_each_entry_safe(fid, tmp, &cinode->openFileList, flist) {
+ rc = cifs_find_fid_lock_conflict(fid, offset, length, type,
+ netfid, conf_lock);
+ if (rc)
+ break;
+ }
+ spin_unlock(&cifs_file_list_lock);
+
+ return rc;
}
/*
@@ -710,17 +720,18 @@
* the server or 1 otherwise.
*/
static int
-cifs_lock_test(struct cifsInodeInfo *cinode, __u64 offset, __u64 length,
- __u8 type, __u16 netfid, struct file_lock *flock)
+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);
bool exist;
mutex_lock(&cinode->lock_mutex);
- exist = __cifs_find_lock_conflict(cinode, offset, length, type, netfid,
- &conf_lock);
+ exist = cifs_find_lock_conflict(cinode, offset, length, type,
+ cfile->netfid, &conf_lock);
if (exist) {
flock->fl_start = conf_lock->offset;
flock->fl_end = conf_lock->offset + conf_lock->length - 1;
@@ -739,10 +750,11 @@
}
static void
-cifs_lock_add(struct cifsInodeInfo *cinode, struct cifsLockInfo *lock)
+cifs_lock_add(struct cifsFileInfo *cfile, struct cifsLockInfo *lock)
{
+ struct cifsInodeInfo *cinode = CIFS_I(cfile->dentry->d_inode);
mutex_lock(&cinode->lock_mutex);
- list_add_tail(&lock->llist, &cinode->llist);
+ list_add_tail(&lock->llist, &cfile->llist);
mutex_unlock(&cinode->lock_mutex);
}
@@ -753,10 +765,11 @@
* 3) -EACCESS, if there is a lock that prevents us and wait is false.
*/
static int
-cifs_lock_add_if(struct cifsInodeInfo *cinode, struct cifsLockInfo *lock,
+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;
@@ -764,9 +777,10 @@
exist = false;
mutex_lock(&cinode->lock_mutex);
- exist = cifs_find_lock_conflict(cinode, lock, &conf_lock);
+ exist = cifs_find_lock_conflict(cinode, lock->offset, lock->length,
+ lock->type, cfile->netfid, &conf_lock);
if (!exist && cinode->can_cache_brlcks) {
- list_add_tail(&lock->llist, &cinode->llist);
+ list_add_tail(&lock->llist, &cfile->llist);
mutex_unlock(&cinode->lock_mutex);
return rc;
}
@@ -888,7 +902,7 @@
for (i = 0; i < 2; i++) {
cur = buf;
num = 0;
- list_for_each_entry_safe(li, tmp, &cinode->llist, llist) {
+ list_for_each_entry_safe(li, tmp, &cfile->llist, llist) {
if (li->type != types[i])
continue;
cur->Pid = cpu_to_le16(li->pid);
@@ -1104,7 +1118,6 @@
__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;
if (posix_lck) {
@@ -1124,8 +1137,7 @@
return rc;
}
- rc = cifs_lock_test(cinode, flock->fl_start, length, type, netfid,
- flock);
+ rc = cifs_lock_test(cfile, flock->fl_start, length, type, flock);
if (!rc)
return rc;
@@ -1212,15 +1224,13 @@
for (i = 0; i < 2; i++) {
cur = buf;
num = 0;
- list_for_each_entry_safe(li, tmp, &cinode->llist, llist) {
+ list_for_each_entry_safe(li, tmp, &cfile->llist, llist) {
if (flock->fl_start > li->offset ||
(flock->fl_start + length) <
(li->offset + li->length))
continue;
if (current->tgid != li->pid)
continue;
- if (cfile->netfid != li->netfid)
- continue;
if (types[i] != li->type)
continue;
if (!cinode->can_cache_brlcks) {
@@ -1233,7 +1243,7 @@
cpu_to_le32((u32)(li->offset>>32));
/*
* We need to save a lock here to let us add
- * it again to the inode list if the unlock
+ * it again to the file's list if the unlock
* range request fails on the server.
*/
list_move(&li->llist, &tmp_llist);
@@ -1247,10 +1257,10 @@
* We failed on the unlock range
* request - add all locks from
* the tmp list to the head of
- * the inode list.
+ * the file's list.
*/
cifs_move_llist(&tmp_llist,
- &cinode->llist);
+ &cfile->llist);
rc = stored_rc;
} else
/*
@@ -1265,7 +1275,7 @@
} else {
/*
* We can cache brlock requests - simply remove
- * a lock from the inode list.
+ * a lock from the file's list.
*/
list_del(&li->llist);
cifs_del_lock_waiters(li);
@@ -1276,7 +1286,7 @@
stored_rc = cifs_lockv(xid, tcon, cfile->netfid,
types[i], num, 0, buf);
if (stored_rc) {
- cifs_move_llist(&tmp_llist, &cinode->llist);
+ cifs_move_llist(&tmp_llist, &cfile->llist);
rc = stored_rc;
} else
cifs_free_llist(&tmp_llist);
@@ -1296,7 +1306,6 @@
__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(file->f_path.dentry->d_inode);
__u16 netfid = cfile->netfid;
if (posix_lck) {
@@ -1323,11 +1332,11 @@
if (lock) {
struct cifsLockInfo *lock;
- lock = cifs_lock_init(flock->fl_start, length, type, netfid);
+ lock = cifs_lock_init(flock->fl_start, length, type);
if (!lock)
return -ENOMEM;
- rc = cifs_lock_add_if(cinode, lock, wait_flag);
+ rc = cifs_lock_add_if(cfile, lock, wait_flag);
if (rc < 0)
kfree(lock);
if (rc <= 0)
@@ -1340,7 +1349,7 @@
goto out;
}
- cifs_lock_add(cinode, lock);
+ cifs_lock_add(cfile, lock);
} else if (unlock)
rc = cifs_unlock_range(cfile, flock, xid);