*/
#include <linux/types.h>
+#include <linux/slab.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/sched.h>
-#include <linux/smp_lock.h>
#include <linux/sunrpc/clnt.h>
-#include <linux/sunrpc/svc.h>
+#include <linux/sunrpc/svc_xprt.h>
#include <linux/lockd/nlm.h>
#include <linux/lockd/lockd.h>
+#include <linux/kthread.h>
#define NLMDBG_FACILITY NLMDBG_SVCLOCK
* The list of blocked locks to retry
*/
static LIST_HEAD(nlm_blocked);
+static DEFINE_SPINLOCK(nlm_blocked_lock);
+
+#ifdef LOCKD_DEBUG
+static const char *nlmdbg_cookie2a(const struct nlm_cookie *cookie)
+{
+ /*
+ * We can get away with a static buffer because we're only
+ * called with BKL held.
+ */
+ static char buf[2*NLM_MAXCOOKIELEN+1];
+ unsigned int i, len = sizeof(buf);
+ char *p = buf;
+
+ len--; /* allow for trailing \0 */
+ if (len < 3)
+ return "???";
+ for (i = 0 ; i < cookie->len ; i++) {
+ if (len < 2) {
+ strcpy(p-3, "...");
+ break;
+ }
+ sprintf(p, "%02x", cookie->data[i]);
+ p += 2;
+ len -= 2;
+ }
+ *p = '\0';
+
+ return buf;
+}
+#endif
/*
* Insert a blocked lock into the global list
*/
static void
-nlmsvc_insert_block(struct nlm_block *block, unsigned long when)
+nlmsvc_insert_block_locked(struct nlm_block *block, unsigned long when)
{
struct nlm_block *b;
struct list_head *pos;
block->b_when = when;
}
+static void nlmsvc_insert_block(struct nlm_block *block, unsigned long when)
+{
+ spin_lock(&nlm_blocked_lock);
+ nlmsvc_insert_block_locked(block, when);
+ spin_unlock(&nlm_blocked_lock);
+}
+
/*
* Remove a block from the global list
*/
nlmsvc_remove_block(struct nlm_block *block)
{
if (!list_empty(&block->b_list)) {
+ spin_lock(&nlm_blocked_lock);
list_del_init(&block->b_list);
+ spin_unlock(&nlm_blocked_lock);
nlmsvc_release_block(block);
}
}
static inline int nlm_cookie_match(struct nlm_cookie *a, struct nlm_cookie *b)
{
- if(a->len != b->len)
+ if (a->len != b->len)
return 0;
- if(memcmp(a->data,b->data,a->len))
+ if (memcmp(a->data, b->data, a->len))
return 0;
return 1;
}
* GRANTED_RES message by cookie, without having to rely on the client's IP
* address. --okir
*/
-static inline struct nlm_block *
-nlmsvc_create_block(struct svc_rqst *rqstp, struct nlm_file *file,
- struct nlm_lock *lock, struct nlm_cookie *cookie)
+static struct nlm_block *
+nlmsvc_create_block(struct svc_rqst *rqstp, struct nlm_host *host,
+ struct nlm_file *file, struct nlm_lock *lock,
+ struct nlm_cookie *cookie)
{
struct nlm_block *block;
- struct nlm_host *host;
struct nlm_rqst *call = NULL;
- /* Create host handle for callback */
- host = nlmsvc_lookup_host(rqstp, lock->caller, lock->len);
- if (host == NULL)
- return NULL;
-
call = nlm_alloc_call(host);
if (call == NULL)
return NULL;
block->b_daemon = rqstp->rq_server;
block->b_host = host;
block->b_file = file;
+ block->b_fl = NULL;
file->f_count++;
/* Add to file's list of blocks */
failed_free:
kfree(block);
failed:
- nlm_release_call(call);
+ nlmsvc_release_call(call);
return NULL;
}
/*
- * Delete a block. If the lock was cancelled or the grant callback
- * failed, unlock is set to 1.
+ * Delete a block.
* It is the caller's responsibility to check whether the file
* can be closed hereafter.
*/
dprintk("lockd: freeing block %p...\n", block);
/* Remove block from file's list of blocks */
- mutex_lock(&file->f_mutex);
list_del_init(&block->b_flist);
mutex_unlock(&file->f_mutex);
nlmsvc_freegrantargs(block->b_call);
- nlm_release_call(block->b_call);
+ nlmsvc_release_call(block->b_call);
nlm_release_file(block->b_file);
kfree(block->b_fl);
kfree(block);
static void nlmsvc_release_block(struct nlm_block *block)
{
if (block != NULL)
- kref_put(&block->b_count, nlmsvc_free_block);
+ kref_put_mutex(&block->b_count, nlmsvc_free_block, &block->b_file->f_mutex);
}
/*
{
if (call->a_args.lock.oh.data != call->a_owner)
kfree(call->a_args.lock.oh.data);
+
+ locks_release_private(&call->a_args.lock.fl);
}
/*
* Deferred lock request handling for non-blocking lock
*/
-static u32
+static __be32
nlmsvc_defer_lock_rqst(struct svc_rqst *rqstp, struct nlm_block *block)
{
- u32 status = nlm_lck_denied_nolocks;
+ __be32 status = nlm_lck_denied_nolocks;
block->b_flags |= B_QUEUED;
status = nlm_drop_reply;
}
dprintk("lockd: nlmsvc_defer_lock_rqst block %p flags %d status %d\n",
- block, block->b_flags, status);
+ block, block->b_flags, ntohl(status));
return status;
}
*/
__be32
nlmsvc_lock(struct svc_rqst *rqstp, struct nlm_file *file,
- struct nlm_lock *lock, int wait, struct nlm_cookie *cookie)
+ struct nlm_host *host, struct nlm_lock *lock, int wait,
+ struct nlm_cookie *cookie, int reclaim)
{
- struct nlm_block *block, *newblock = NULL;
+ struct nlm_block *block = NULL;
int error;
__be32 ret;
dprintk("lockd: nlmsvc_lock(%s/%ld, ty=%d, pi=%d, %Ld-%Ld, bl=%d)\n",
- file->f_file->f_path.dentry->d_inode->i_sb->s_id,
- file->f_file->f_path.dentry->d_inode->i_ino,
+ file_inode(file->f_file)->i_sb->s_id,
+ file_inode(file->f_file)->i_ino,
lock->fl.fl_type, lock->fl.fl_pid,
(long long)lock->fl.fl_start,
(long long)lock->fl.fl_end,
wait);
-
- lock->fl.fl_flags &= ~FL_SLEEP;
-again:
/* Lock file against concurrent access */
mutex_lock(&file->f_mutex);
- /* Get existing block (in case client is busy-waiting) */
+ /* Get existing block (in case client is busy-waiting)
+ * or create new block
+ */
block = nlmsvc_lookup_block(file, lock);
if (block == NULL) {
- if (newblock != NULL)
- lock = &newblock->b_call->a_args.lock;
- } else
+ block = nlmsvc_create_block(rqstp, host, file, lock, cookie);
+ ret = nlm_lck_denied_nolocks;
+ if (block == NULL)
+ goto out;
lock = &block->b_call->a_args.lock;
+ } else
+ lock->fl.fl_flags &= ~FL_SLEEP;
- error = posix_lock_file(file->f_file, &lock->fl, NULL);
- lock->fl.fl_flags &= ~FL_SLEEP;
+ if (block->b_flags & B_QUEUED) {
+ dprintk("lockd: nlmsvc_lock deferred block %p flags %d\n",
+ block, block->b_flags);
+ if (block->b_granted) {
+ nlmsvc_unlink_block(block);
+ ret = nlm_granted;
+ goto out;
+ }
+ if (block->b_flags & B_TIMED_OUT) {
+ nlmsvc_unlink_block(block);
+ ret = nlm_lck_denied;
+ goto out;
+ }
+ ret = nlm_drop_reply;
+ goto out;
+ }
+
+ if (locks_in_grace(SVC_NET(rqstp)) && !reclaim) {
+ ret = nlm_lck_denied_grace_period;
+ goto out;
+ }
+ if (reclaim && !locks_in_grace(SVC_NET(rqstp))) {
+ ret = nlm_lck_denied_grace_period;
+ goto out;
+ }
- dprintk("lockd: posix_lock_file returned %d\n", error);
+ if (!wait)
+ lock->fl.fl_flags &= ~FL_SLEEP;
+ error = vfs_lock_file(file->f_file, F_SETLK, &lock->fl, NULL);
+ lock->fl.fl_flags &= ~FL_SLEEP;
- switch(error) {
+ dprintk("lockd: vfs_lock_file returned %d\n", error);
+ switch (error) {
case 0:
ret = nlm_granted;
goto out;
case -EAGAIN:
- break;
+ /*
+ * If this is a blocking request for an
+ * already pending lock request then we need
+ * to put it back on lockd's block list
+ */
+ if (wait)
+ break;
+ ret = nlm_lck_denied;
+ goto out;
+ case FILE_LOCK_DEFERRED:
+ if (wait)
+ break;
+ /* Filesystem lock operation is in progress
+ Add it to the queue waiting for callback */
+ ret = nlmsvc_defer_lock_rqst(rqstp, block);
+ goto out;
case -EDEADLK:
ret = nlm_deadlock;
goto out;
goto out;
}
- ret = nlm_lck_denied;
- if (!wait)
- goto out;
-
ret = nlm_lck_blocked;
- if (block != NULL)
- goto out;
-
- /* If we don't have a block, create and initialize it. Then
- * retry because we may have slept in kmalloc. */
- /* We have to release f_mutex as nlmsvc_create_block may try to
- * to claim it while doing host garbage collection */
- if (newblock == NULL) {
- mutex_unlock(&file->f_mutex);
- dprintk("lockd: blocking on this lock (allocating).\n");
- if (!(newblock = nlmsvc_create_block(rqstp, file, lock, cookie)))
- return nlm_lck_denied_nolocks;
- goto again;
- }
/* Append to list of blocked */
- nlmsvc_insert_block(newblock, NLM_NEVER);
+ nlmsvc_insert_block(block, NLM_NEVER);
out:
mutex_unlock(&file->f_mutex);
- nlmsvc_release_block(newblock);
nlmsvc_release_block(block);
dprintk("lockd: nlmsvc_lock returned %u\n", ret);
return ret;
* Test for presence of a conflicting lock.
*/
__be32
-nlmsvc_testlock(struct nlm_file *file, struct nlm_lock *lock,
- struct nlm_lock *conflock)
+nlmsvc_testlock(struct svc_rqst *rqstp, struct nlm_file *file,
+ struct nlm_host *host, struct nlm_lock *lock,
+ struct nlm_lock *conflock, struct nlm_cookie *cookie)
{
+ struct nlm_block *block = NULL;
+ int error;
+ __be32 ret;
+
dprintk("lockd: nlmsvc_testlock(%s/%ld, ty=%d, %Ld-%Ld)\n",
- file->f_file->f_path.dentry->d_inode->i_sb->s_id,
- file->f_file->f_path.dentry->d_inode->i_ino,
+ file_inode(file->f_file)->i_sb->s_id,
+ file_inode(file->f_file)->i_ino,
lock->fl.fl_type,
(long long)lock->fl.fl_start,
(long long)lock->fl.fl_end);
- if (posix_test_lock(file->f_file, &lock->fl)) {
- dprintk("lockd: conflicting lock(ty=%d, %Ld-%Ld)\n",
- lock->fl.fl_type,
- (long long)lock->fl.fl_start,
- (long long)lock->fl.fl_end);
- conflock->caller = "somehost"; /* FIXME */
- conflock->len = strlen(conflock->caller);
- conflock->oh.len = 0; /* don't return OH info */
- conflock->svid = lock->fl.fl_pid;
- conflock->fl.fl_type = lock->fl.fl_type;
- conflock->fl.fl_start = lock->fl.fl_start;
- conflock->fl.fl_end = lock->fl.fl_end;
- return nlm_lck_denied;
+ /* Get existing block (in case client is busy-waiting) */
+ block = nlmsvc_lookup_block(file, lock);
+
+ if (block == NULL) {
+ struct file_lock *conf = kzalloc(sizeof(*conf), GFP_KERNEL);
+
+ if (conf == NULL)
+ return nlm_granted;
+ block = nlmsvc_create_block(rqstp, host, file, lock, cookie);
+ if (block == NULL) {
+ kfree(conf);
+ return nlm_granted;
+ }
+ block->b_fl = conf;
+ }
+ if (block->b_flags & B_QUEUED) {
+ dprintk("lockd: nlmsvc_testlock deferred block %p flags %d fl %p\n",
+ block, block->b_flags, block->b_fl);
+ if (block->b_flags & B_TIMED_OUT) {
+ nlmsvc_unlink_block(block);
+ ret = nlm_lck_denied;
+ goto out;
+ }
+ if (block->b_flags & B_GOT_CALLBACK) {
+ nlmsvc_unlink_block(block);
+ if (block->b_fl != NULL
+ && block->b_fl->fl_type != F_UNLCK) {
+ lock->fl = *block->b_fl;
+ goto conf_lock;
+ } else {
+ ret = nlm_granted;
+ goto out;
+ }
+ }
+ ret = nlm_drop_reply;
+ goto out;
+ }
+
+ if (locks_in_grace(SVC_NET(rqstp))) {
+ ret = nlm_lck_denied_grace_period;
+ goto out;
+ }
+ error = vfs_test_lock(file->f_file, &lock->fl);
+ if (error == FILE_LOCK_DEFERRED) {
+ ret = nlmsvc_defer_lock_rqst(rqstp, block);
+ goto out;
+ }
+ if (error) {
+ ret = nlm_lck_denied_nolocks;
+ goto out;
+ }
+ if (lock->fl.fl_type == F_UNLCK) {
+ ret = nlm_granted;
+ goto out;
}
- return nlm_granted;
+conf_lock:
+ dprintk("lockd: conflicting lock(ty=%d, %Ld-%Ld)\n",
+ lock->fl.fl_type, (long long)lock->fl.fl_start,
+ (long long)lock->fl.fl_end);
+ conflock->caller = "somehost"; /* FIXME */
+ conflock->len = strlen(conflock->caller);
+ conflock->oh.len = 0; /* don't return OH info */
+ conflock->svid = lock->fl.fl_pid;
+ conflock->fl.fl_type = lock->fl.fl_type;
+ conflock->fl.fl_start = lock->fl.fl_start;
+ conflock->fl.fl_end = lock->fl.fl_end;
+ ret = nlm_lck_denied;
+out:
+ if (block)
+ nlmsvc_release_block(block);
+ return ret;
}
/*
* must be removed.
*/
__be32
-nlmsvc_unlock(struct nlm_file *file, struct nlm_lock *lock)
+nlmsvc_unlock(struct net *net, struct nlm_file *file, struct nlm_lock *lock)
{
int error;
dprintk("lockd: nlmsvc_unlock(%s/%ld, pi=%d, %Ld-%Ld)\n",
- file->f_file->f_path.dentry->d_inode->i_sb->s_id,
- file->f_file->f_path.dentry->d_inode->i_ino,
+ file_inode(file->f_file)->i_sb->s_id,
+ file_inode(file->f_file)->i_ino,
lock->fl.fl_pid,
(long long)lock->fl.fl_start,
(long long)lock->fl.fl_end);
/* First, cancel any lock that might be there */
- nlmsvc_cancel_blocked(file, lock);
+ nlmsvc_cancel_blocked(net, file, lock);
lock->fl.fl_type = F_UNLCK;
- error = posix_lock_file(file->f_file, &lock->fl, NULL);
+ error = vfs_lock_file(file->f_file, F_SETLK, &lock->fl, NULL);
return (error < 0)? nlm_lck_denied_nolocks : nlm_granted;
}
* The calling procedure must check whether the file can be closed.
*/
__be32
-nlmsvc_cancel_blocked(struct nlm_file *file, struct nlm_lock *lock)
+nlmsvc_cancel_blocked(struct net *net, struct nlm_file *file, struct nlm_lock *lock)
{
struct nlm_block *block;
int status = 0;
dprintk("lockd: nlmsvc_cancel(%s/%ld, pi=%d, %Ld-%Ld)\n",
- file->f_file->f_path.dentry->d_inode->i_sb->s_id,
- file->f_file->f_path.dentry->d_inode->i_ino,
+ file_inode(file->f_file)->i_sb->s_id,
+ file_inode(file->f_file)->i_ino,
lock->fl.fl_pid,
(long long)lock->fl.fl_start,
(long long)lock->fl.fl_end);
+ if (locks_in_grace(net))
+ return nlm_lck_denied_grace_period;
+
mutex_lock(&file->f_mutex);
block = nlmsvc_lookup_block(file, lock);
mutex_unlock(&file->f_mutex);
if (block != NULL) {
+ vfs_cancel_lock(block->b_file->f_file,
+ &block->b_call->a_args.lock.fl);
status = nlmsvc_unlink_block(block);
nlmsvc_release_block(block);
}
/*
* This is a callback from the filesystem for VFS file lock requests.
- * It will be used if fl_grant is defined and the filesystem can not
+ * It will be used if lm_grant is defined and the filesystem can not
* respond to the request immediately.
* For GETLK request it will copy the reply to the nlm_block.
* For SETLK or SETLKW request it will get the local posix lock.
else
block->b_flags |= B_TIMED_OUT;
if (conf) {
- block->b_fl = kzalloc(sizeof(struct file_lock), GFP_KERNEL);
if (block->b_fl)
- locks_copy_lock(block->b_fl, conf);
+ __locks_copy_lock(block->b_fl, conf);
}
}
struct nlm_block *block;
int rc = -ENOENT;
- lock_kernel();
+ spin_lock(&nlm_blocked_lock);
list_for_each_entry(block, &nlm_blocked, b_list) {
if (nlm_compare_locks(&block->b_call->a_args.lock.fl, fl)) {
dprintk("lockd: nlmsvc_notify_blocked block %p flags %d\n",
} else if (result == 0)
block->b_granted = 1;
- nlmsvc_insert_block(block, 0);
+ nlmsvc_insert_block_locked(block, 0);
svc_wake_up(block->b_daemon);
rc = 0;
break;
}
}
- unlock_kernel();
+ spin_unlock(&nlm_blocked_lock);
if (rc == -ENOENT)
printk(KERN_WARNING "lockd: grant for unknown block\n");
return rc;
struct nlm_block *block;
dprintk("lockd: VFS unblock notification for block %p\n", fl);
+ spin_lock(&nlm_blocked_lock);
list_for_each_entry(block, &nlm_blocked, b_list) {
if (nlm_compare_locks(&block->b_call->a_args.lock.fl, fl)) {
- nlmsvc_insert_block(block, 0);
+ nlmsvc_insert_block_locked(block, 0);
+ spin_unlock(&nlm_blocked_lock);
svc_wake_up(block->b_daemon);
return;
}
}
-
+ spin_unlock(&nlm_blocked_lock);
printk(KERN_WARNING "lockd: notification for unknown block!\n");
}
return fl1->fl_owner == fl2->fl_owner && fl1->fl_pid == fl2->fl_pid;
}
-struct lock_manager_operations nlmsvc_lock_operations = {
- .fl_compare_owner = nlmsvc_same_owner,
- .fl_notify = nlmsvc_notify_blocked,
- .fl_grant = nlmsvc_grant_deferred,
+const struct lock_manager_operations nlmsvc_lock_operations = {
+ .lm_compare_owner = nlmsvc_same_owner,
+ .lm_notify = nlmsvc_notify_blocked,
+ .lm_grant = nlmsvc_grant_deferred,
};
/*
/* Try the lock operation again */
lock->fl.fl_flags |= FL_SLEEP;
- error = posix_lock_file(file->f_file, &lock->fl, NULL);
+ error = vfs_lock_file(file->f_file, F_SETLK, &lock->fl, NULL);
lock->fl.fl_flags &= ~FL_SLEEP;
switch (error) {
case 0:
break;
- case -EAGAIN:
- dprintk("lockd: lock still blocked\n");
+ case FILE_LOCK_DEFERRED:
+ dprintk("lockd: lock still blocked error %d\n", error);
nlmsvc_insert_block(block, NLM_NEVER);
nlmsvc_release_block(block);
return;
default:
printk(KERN_WARNING "lockd: unexpected error %d in %s!\n",
- -error, __FUNCTION__);
+ -error, __func__);
nlmsvc_insert_block(block, 10 * HZ);
nlmsvc_release_block(block);
return;
dprintk("lockd: GRANTing blocked lock.\n");
block->b_granted = 1;
- /* Schedule next grant callback in 30 seconds */
- nlmsvc_insert_block(block, 30 * HZ);
+ /* keep block on the list, but don't reattempt until the RPC
+ * completes or the submission fails
+ */
+ nlmsvc_insert_block(block, NLM_NEVER);
+
+ /* Call the client -- use a soft RPC task since nlmsvc_retry_blocked
+ * will queue up a new one if this one times out
+ */
+ error = nlm_async_call(block->b_call, NLMPROC_GRANTED_MSG,
+ &nlmsvc_grant_ops);
- /* Call the client */
- nlm_async_call(block->b_call, NLMPROC_GRANTED_MSG, &nlmsvc_grant_ops);
+ /* RPC submission failed, wait a bit and retry */
+ if (error < 0)
+ nlmsvc_insert_block(block, 10 * HZ);
}
/*
dprintk("lockd: GRANT_MSG RPC callback\n");
+ spin_lock(&nlm_blocked_lock);
+ /* if the block is not on a list at this point then it has
+ * been invalidated. Don't try to requeue it.
+ *
+ * FIXME: it's possible that the block is removed from the list
+ * after this check but before the nlmsvc_insert_block. In that
+ * case it will be added back. Perhaps we need better locking
+ * for nlm_blocked?
+ */
+ if (list_empty(&block->b_list))
+ goto out;
+
/* Technically, we should down the file semaphore here. Since we
* move the block towards the head of the queue only, no harm
* can be done, though. */
/* Call was successful, now wait for client callback */
timeout = 60 * HZ;
}
- nlmsvc_insert_block(block, timeout);
+ nlmsvc_insert_block_locked(block, timeout);
svc_wake_up(block->b_daemon);
+out:
+ spin_unlock(&nlm_blocked_lock);
}
+/*
+ * FIXME: nlmsvc_release_block() grabs a mutex. This is not allowed for an
+ * .rpc_release rpc_call_op
+ */
static void nlmsvc_grant_release(void *data)
{
struct nlm_rqst *call = data;
-
nlmsvc_release_block(call->a_block);
}
unsigned long timeout = MAX_SCHEDULE_TIMEOUT;
struct nlm_block *block;
- while (!list_empty(&nlm_blocked)) {
+ while (!list_empty(&nlm_blocked) && !kthread_should_stop()) {
block = list_entry(nlm_blocked.next, struct nlm_block, b_list);
if (block->b_when == NLM_NEVER)
break;
- if (time_after(block->b_when,jiffies)) {
+ if (time_after(block->b_when, jiffies)) {
timeout = block->b_when - jiffies;
break;
}
Code Review / linux-3.10.git / blobdiff