* Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
*/
-#include <linux/config.h>
#include <linux/types.h>
+#include <linux/slab.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/sunrpc/svc.h>
#include <linux/lockd/nlm.h>
#include <linux/lockd/lockd.h>
+#include <linux/kthread.h>
#define NLMDBG_FACILITY NLMDBG_SVCLOCK
#define nlm_deadlock nlm_lck_denied
#endif
+static void nlmsvc_release_block(struct nlm_block *block);
static void nlmsvc_insert_block(struct nlm_block *block, unsigned long);
-static int nlmsvc_remove_block(struct nlm_block *block);
-static void nlmsvc_grant_callback(struct rpc_task *task);
+static void nlmsvc_remove_block(struct nlm_block *block);
+
+static int nlmsvc_setgrantargs(struct nlm_rqst *call, struct nlm_lock *lock);
+static void nlmsvc_freegrantargs(struct nlm_rqst *call);
+static const struct rpc_call_ops nlmsvc_grant_ops;
/*
* The list of blocked locks to retry
*/
-static struct nlm_block * nlm_blocked;
+static LIST_HEAD(nlm_blocked);
/*
* Insert a blocked lock into the global list
static void
nlmsvc_insert_block(struct nlm_block *block, unsigned long when)
{
- struct nlm_block **bp, *b;
+ struct nlm_block *b;
+ struct list_head *pos;
dprintk("lockd: nlmsvc_insert_block(%p, %ld)\n", block, when);
- if (block->b_queued)
- nlmsvc_remove_block(block);
- bp = &nlm_blocked;
+ if (list_empty(&block->b_list)) {
+ kref_get(&block->b_count);
+ } else {
+ list_del_init(&block->b_list);
+ }
+
+ pos = &nlm_blocked;
if (when != NLM_NEVER) {
if ((when += jiffies) == NLM_NEVER)
when ++;
- while ((b = *bp) && time_before_eq(b->b_when,when) && b->b_when != NLM_NEVER)
- bp = &b->b_next;
- } else
- while ((b = *bp) != 0)
- bp = &b->b_next;
+ list_for_each(pos, &nlm_blocked) {
+ b = list_entry(pos, struct nlm_block, b_list);
+ if (time_after(b->b_when,when) || b->b_when == NLM_NEVER)
+ break;
+ }
+ /* On normal exit from the loop, pos == &nlm_blocked,
+ * so we will be adding to the end of the list - good
+ */
+ }
- block->b_queued = 1;
+ list_add_tail(&block->b_list, pos);
block->b_when = when;
- block->b_next = b;
- *bp = block;
}
/*
* Remove a block from the global list
*/
-static int
+static inline void
nlmsvc_remove_block(struct nlm_block *block)
{
- struct nlm_block **bp, *b;
-
- if (!block->b_queued)
- return 1;
- for (bp = &nlm_blocked; (b = *bp) != 0; bp = &b->b_next) {
- if (b == block) {
- *bp = block->b_next;
- block->b_queued = 0;
- return 1;
- }
+ if (!list_empty(&block->b_list)) {
+ list_del_init(&block->b_list);
+ nlmsvc_release_block(block);
}
-
- return 0;
}
/*
- * Find a block for a given lock and optionally remove it from
- * the list.
+ * Find a block for a given lock
*/
static struct nlm_block *
-nlmsvc_lookup_block(struct nlm_file *file, struct nlm_lock *lock, int remove)
+nlmsvc_lookup_block(struct nlm_file *file, struct nlm_lock *lock)
{
- struct nlm_block **head, *block;
+ struct nlm_block *block;
struct file_lock *fl;
dprintk("lockd: nlmsvc_lookup_block f=%p pd=%d %Ld-%Ld ty=%d\n",
file, lock->fl.fl_pid,
(long long)lock->fl.fl_start,
(long long)lock->fl.fl_end, lock->fl.fl_type);
- for (head = &nlm_blocked; (block = *head) != 0; head = &block->b_next) {
- fl = &block->b_call.a_args.lock.fl;
+ list_for_each_entry(block, &nlm_blocked, b_list) {
+ fl = &block->b_call->a_args.lock.fl;
dprintk("lockd: check f=%p pd=%d %Ld-%Ld ty=%d cookie=%s\n",
block->b_file, fl->fl_pid,
(long long)fl->fl_start,
(long long)fl->fl_end, fl->fl_type,
- nlmdbg_cookie2a(&block->b_call.a_args.cookie));
+ nlmdbg_cookie2a(&block->b_call->a_args.cookie));
if (block->b_file == file && nlm_compare_locks(fl, &lock->fl)) {
- if (remove) {
- *head = block->b_next;
- block->b_queued = 0;
- }
+ kref_get(&block->b_count);
return 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;
}
* Find a block with a given NLM cookie.
*/
static inline struct nlm_block *
-nlmsvc_find_block(struct nlm_cookie *cookie, struct sockaddr_in *sin)
+nlmsvc_find_block(struct nlm_cookie *cookie)
{
struct nlm_block *block;
- for (block = nlm_blocked; block; block = block->b_next) {
- dprintk("cookie: head of blocked queue %p, block %p\n",
- nlm_blocked, block);
- if (nlm_cookie_match(&block->b_call.a_args.cookie,cookie)
- && nlm_cmp_addr(sin, &block->b_host->h_addr))
- break;
+ list_for_each_entry(block, &nlm_blocked, b_list) {
+ if (nlm_cookie_match(&block->b_call->a_args.cookie,cookie))
+ goto found;
}
+ return NULL;
+
+found:
+ dprintk("nlmsvc_find_block(%s): block=%p\n", nlmdbg_cookie2a(cookie), block);
+ kref_get(&block->b_count);
return block;
}
* request, but (as I found out later) that's because some implementations
* do just this. Never mind the standards comittees, they support our
* logging industries.
+ *
+ * 10 years later: I hope we can safely ignore these old and broken
+ * clients by now. Let's fix this so we can uniquely identify an incoming
+ * 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;
+ struct nlm_rqst *call = NULL;
- /* Create host handle for callback */
- host = nlmclnt_lookup_host(&rqstp->rq_addr,
- rqstp->rq_prot, rqstp->rq_vers);
- if (host == NULL)
+ nlm_get_host(host);
+ call = nlm_alloc_call(host);
+ if (call == NULL)
return NULL;
/* Allocate memory for block, and initialize arguments */
- if (!(block = (struct nlm_block *) kmalloc(sizeof(*block), GFP_KERNEL)))
+ block = kzalloc(sizeof(*block), GFP_KERNEL);
+ if (block == NULL)
goto failed;
- memset(block, 0, sizeof(*block));
- locks_init_lock(&block->b_call.a_args.lock.fl);
- locks_init_lock(&block->b_call.a_res.lock.fl);
+ kref_init(&block->b_count);
+ INIT_LIST_HEAD(&block->b_list);
+ INIT_LIST_HEAD(&block->b_flist);
- if (!nlmclnt_setgrantargs(&block->b_call, lock))
+ if (!nlmsvc_setgrantargs(call, lock))
goto failed_free;
/* Set notifier function for VFS, and init args */
- block->b_call.a_args.lock.fl.fl_lmops = &nlmsvc_lock_operations;
- block->b_call.a_args.cookie = *cookie; /* see above */
+ call->a_args.lock.fl.fl_flags |= FL_SLEEP;
+ call->a_args.lock.fl.fl_lmops = &nlmsvc_lock_operations;
+ nlmclnt_next_cookie(&call->a_args.cookie);
dprintk("lockd: created block %p...\n", block);
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 */
- block->b_fnext = file->f_blocks;
- file->f_blocks = block;
+ list_add(&block->b_flist, &file->f_blocks);
/* Set up RPC arguments for callback */
- call = &block->b_call;
- call->a_host = host;
+ block->b_call = call;
call->a_flags = RPC_TASK_ASYNC;
+ call->a_block = block;
return block;
failed_free:
kfree(block);
failed:
- nlm_release_host(host);
+ nlm_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.
*/
-static void
-nlmsvc_delete_block(struct nlm_block *block, int unlock)
+static int nlmsvc_unlink_block(struct nlm_block *block)
{
- struct file_lock *fl = &block->b_call.a_args.lock.fl;
- struct nlm_file *file = block->b_file;
- struct nlm_block **bp;
-
- dprintk("lockd: deleting block %p...\n", block);
+ int status;
+ dprintk("lockd: unlinking block %p...\n", block);
/* Remove block from list */
+ status = posix_unblock_lock(block->b_file->f_file, &block->b_call->a_args.lock.fl);
nlmsvc_remove_block(block);
- if (fl->fl_next)
- posix_unblock_lock(file->f_file, fl);
- if (unlock) {
- fl->fl_type = F_UNLCK;
- posix_lock_file(file->f_file, fl);
- block->b_granted = 0;
- }
+ return status;
+}
- /* If the block is in the middle of a GRANT callback,
- * don't kill it yet. */
- if (block->b_incall) {
- nlmsvc_insert_block(block, NLM_NEVER);
- block->b_done = 1;
- return;
- }
+static void nlmsvc_free_block(struct kref *kref)
+{
+ struct nlm_block *block = container_of(kref, struct nlm_block, b_count);
+ struct nlm_file *file = block->b_file;
+
+ dprintk("lockd: freeing block %p...\n", block);
/* Remove block from file's list of blocks */
- for (bp = &file->f_blocks; *bp; bp = &(*bp)->b_fnext) {
- if (*bp == block) {
- *bp = block->b_fnext;
- break;
- }
+ 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);
+ 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);
+}
+
+/*
+ * Loop over all blocks and delete blocks held by
+ * a matching host.
+ */
+void nlmsvc_traverse_blocks(struct nlm_host *host,
+ struct nlm_file *file,
+ nlm_host_match_fn_t match)
+{
+ struct nlm_block *block, *next;
+
+restart:
+ mutex_lock(&file->f_mutex);
+ list_for_each_entry_safe(block, next, &file->f_blocks, b_flist) {
+ if (!match(block->b_host, host))
+ continue;
+ /* Do not destroy blocks that are not on
+ * the global retry list - why? */
+ if (list_empty(&block->b_list))
+ continue;
+ kref_get(&block->b_count);
+ mutex_unlock(&file->f_mutex);
+ nlmsvc_unlink_block(block);
+ nlmsvc_release_block(block);
+ goto restart;
}
+ mutex_unlock(&file->f_mutex);
+}
- if (block->b_host)
- nlm_release_host(block->b_host);
- nlmclnt_freegrantargs(&block->b_call);
- kfree(block);
+/*
+ * Initialize arguments for GRANTED call. The nlm_rqst structure
+ * has been cleared already.
+ */
+static int nlmsvc_setgrantargs(struct nlm_rqst *call, struct nlm_lock *lock)
+{
+ locks_copy_lock(&call->a_args.lock.fl, &lock->fl);
+ memcpy(&call->a_args.lock.fh, &lock->fh, sizeof(call->a_args.lock.fh));
+ call->a_args.lock.caller = utsname()->nodename;
+ call->a_args.lock.oh.len = lock->oh.len;
+
+ /* set default data area */
+ call->a_args.lock.oh.data = call->a_owner;
+ call->a_args.lock.svid = lock->fl.fl_pid;
+
+ if (lock->oh.len > NLMCLNT_OHSIZE) {
+ void *data = kmalloc(lock->oh.len, GFP_KERNEL);
+ if (!data)
+ return 0;
+ call->a_args.lock.oh.data = (u8 *) data;
+ }
+
+ memcpy(call->a_args.lock.oh.data, lock->oh.data, lock->oh.len);
+ return 1;
+}
+
+static void nlmsvc_freegrantargs(struct nlm_rqst *call)
+{
+ 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);
}
/*
- * Loop over all blocks and perform the action specified.
- * (NLM_ACT_CHECK handled by nlmsvc_inspect_file).
+ * Deferred lock request handling for non-blocking lock
*/
-int
-nlmsvc_traverse_blocks(struct nlm_host *host, struct nlm_file *file, int action)
+static __be32
+nlmsvc_defer_lock_rqst(struct svc_rqst *rqstp, struct nlm_block *block)
{
- struct nlm_block *block, *next;
-
- down(&file->f_sema);
- for (block = file->f_blocks; block; block = next) {
- next = block->b_fnext;
- if (action == NLM_ACT_MARK)
- block->b_host->h_inuse = 1;
- else if (action == NLM_ACT_UNLOCK) {
- if (host == NULL || host == block->b_host)
- nlmsvc_delete_block(block, 1);
- }
+ __be32 status = nlm_lck_denied_nolocks;
+
+ block->b_flags |= B_QUEUED;
+
+ nlmsvc_insert_block(block, NLM_TIMEOUT);
+
+ block->b_cache_req = &rqstp->rq_chandle;
+ if (rqstp->rq_chandle.defer) {
+ block->b_deferred_req =
+ rqstp->rq_chandle.defer(block->b_cache_req);
+ if (block->b_deferred_req != NULL)
+ status = nlm_drop_reply;
}
- up(&file->f_sema);
- return 0;
+ dprintk("lockd: nlmsvc_defer_lock_rqst block %p flags %d status %d\n",
+ block, block->b_flags, ntohl(status));
+
+ return status;
}
/*
* Attempt to establish a lock, and if it can't be granted, block it
* if required.
*/
-u32
+__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 file_lock *conflock;
- struct nlm_block *block;
+ 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_dentry->d_inode->i_sb->s_id,
- file->f_file->f_dentry->d_inode->i_ino,
+ file->f_file->f_path.dentry->d_inode->i_sb->s_id,
+ file->f_file->f_path.dentry->d_inode->i_ino,
lock->fl.fl_type, lock->fl.fl_pid,
(long long)lock->fl.fl_start,
(long long)lock->fl.fl_end,
wait);
-
- /* Get existing block (in case client is busy-waiting) */
- block = nlmsvc_lookup_block(file, lock, 0);
-
- lock->fl.fl_flags |= FL_LOCKD;
-
-again:
/* Lock file against concurrent access */
- down(&file->f_sema);
-
- if (!(conflock = posix_test_lock(file->f_file, &lock->fl))) {
- error = posix_lock_file(file->f_file, &lock->fl);
-
- if (block)
- nlmsvc_delete_block(block, 0);
- up(&file->f_sema);
-
- dprintk("lockd: posix_lock_file returned %d\n", -error);
- switch(-error) {
- case 0:
- return nlm_granted;
- case EDEADLK:
- return nlm_deadlock;
- case EAGAIN:
- return nlm_lck_denied;
- default: /* includes ENOLCK */
- return nlm_lck_denied_nolocks;
+ mutex_lock(&file->f_mutex);
+ /* Get existing block (in case client is busy-waiting)
+ * or create new block
+ */
+ block = nlmsvc_lookup_block(file, lock);
+ if (block == NULL) {
+ 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;
+
+ 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 (!wait) {
- up(&file->f_sema);
- return nlm_lck_denied;
+ if (locks_in_grace() && !reclaim) {
+ ret = nlm_lck_denied_grace_period;
+ goto out;
}
-
- if (posix_locks_deadlock(&lock->fl, conflock)) {
- up(&file->f_sema);
- return nlm_deadlock;
+ if (reclaim && !locks_in_grace()) {
+ ret = nlm_lck_denied_grace_period;
+ 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_sema as nlmsvc_create_block may try to
- * to claim it while doing host garbage collection */
- if (block == NULL) {
- up(&file->f_sema);
- dprintk("lockd: blocking on this lock (allocating).\n");
- if (!(block = nlmsvc_create_block(rqstp, file, lock, cookie)))
- return nlm_lck_denied_nolocks;
- goto again;
+ 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;
+
+ dprintk("lockd: vfs_lock_file returned %d\n", error);
+ switch (error) {
+ case 0:
+ ret = nlm_granted;
+ goto out;
+ case -EAGAIN:
+ /*
+ * 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;
+ default: /* includes ENOLCK */
+ ret = nlm_lck_denied_nolocks;
+ goto out;
}
+ ret = nlm_lck_blocked;
+
/* Append to list of blocked */
nlmsvc_insert_block(block, NLM_NEVER);
-
- if (list_empty(&block->b_call.a_args.lock.fl.fl_block)) {
- /* Now add block to block list of the conflicting lock
- if we haven't done so. */
- dprintk("lockd: blocking on this lock.\n");
- posix_block_lock(conflock, &block->b_call.a_args.lock.fl);
- }
-
- up(&file->f_sema);
- return nlm_lck_blocked;
+out:
+ mutex_unlock(&file->f_mutex);
+ nlmsvc_release_block(block);
+ dprintk("lockd: nlmsvc_lock returned %u\n", ret);
+ return ret;
}
/*
* Test for presence of a conflicting lock.
*/
-u32
-nlmsvc_testlock(struct nlm_file *file, struct nlm_lock *lock,
- struct nlm_lock *conflock)
+__be32
+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 file_lock *fl;
+ struct nlm_block *block = NULL;
+ int error;
+ __be32 ret;
dprintk("lockd: nlmsvc_testlock(%s/%ld, ty=%d, %Ld-%Ld)\n",
- file->f_file->f_dentry->d_inode->i_sb->s_id,
- file->f_file->f_dentry->d_inode->i_ino,
+ file->f_file->f_path.dentry->d_inode->i_sb->s_id,
+ file->f_file->f_path.dentry->d_inode->i_ino,
lock->fl.fl_type,
(long long)lock->fl.fl_start,
(long long)lock->fl.fl_end);
- if ((fl = posix_test_lock(file->f_file, &lock->fl)) != NULL) {
- dprintk("lockd: conflicting lock(ty=%d, %Ld-%Ld)\n",
- fl->fl_type, (long long)fl->fl_start,
- (long long)fl->fl_end);
- conflock->caller = "somehost"; /* FIXME */
- conflock->oh.len = 0; /* don't return OH info */
- conflock->fl = *fl;
- 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()) {
+ 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;
}
/*
* afterwards. In this case the block will still be there, and hence
* must be removed.
*/
-u32
+__be32
nlmsvc_unlock(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_dentry->d_inode->i_sb->s_id,
- file->f_file->f_dentry->d_inode->i_ino,
+ file->f_file->f_path.dentry->d_inode->i_sb->s_id,
+ file->f_file->f_path.dentry->d_inode->i_ino,
lock->fl.fl_pid,
(long long)lock->fl.fl_start,
(long long)lock->fl.fl_end);
nlmsvc_cancel_blocked(file, lock);
lock->fl.fl_type = F_UNLCK;
- error = posix_lock_file(file->f_file, &lock->fl);
+ error = vfs_lock_file(file->f_file, F_SETLK, &lock->fl, NULL);
return (error < 0)? nlm_lck_denied_nolocks : nlm_granted;
}
* be in progress.
* The calling procedure must check whether the file can be closed.
*/
-u32
+__be32
nlmsvc_cancel_blocked(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_dentry->d_inode->i_sb->s_id,
- file->f_file->f_dentry->d_inode->i_ino,
+ file->f_file->f_path.dentry->d_inode->i_sb->s_id,
+ file->f_file->f_path.dentry->d_inode->i_ino,
lock->fl.fl_pid,
(long long)lock->fl.fl_start,
(long long)lock->fl.fl_end);
- down(&file->f_sema);
- if ((block = nlmsvc_lookup_block(file, lock, 1)) != NULL)
- nlmsvc_delete_block(block, 1);
- up(&file->f_sema);
- return nlm_granted;
+ if (locks_in_grace())
+ 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);
+ }
+ return status ? nlm_lck_denied : nlm_granted;
+}
+
+/*
+ * 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
+ * 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.
+ * In all cases it will move the block to the head of nlm_blocked q where
+ * nlmsvc_retry_blocked() can send back a reply for SETLKW or revisit the
+ * deferred rpc for GETLK and SETLK.
+ */
+static void
+nlmsvc_update_deferred_block(struct nlm_block *block, struct file_lock *conf,
+ int result)
+{
+ block->b_flags |= B_GOT_CALLBACK;
+ if (result == 0)
+ block->b_granted = 1;
+ else
+ block->b_flags |= B_TIMED_OUT;
+ if (conf) {
+ if (block->b_fl)
+ __locks_copy_lock(block->b_fl, conf);
+ }
+}
+
+static int nlmsvc_grant_deferred(struct file_lock *fl, struct file_lock *conf,
+ int result)
+{
+ struct nlm_block *block;
+ int rc = -ENOENT;
+
+ lock_kernel();
+ 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",
+ block, block->b_flags);
+ if (block->b_flags & B_QUEUED) {
+ if (block->b_flags & B_TIMED_OUT) {
+ rc = -ENOLCK;
+ break;
+ }
+ nlmsvc_update_deferred_block(block, conf, result);
+ } else if (result == 0)
+ block->b_granted = 1;
+
+ nlmsvc_insert_block(block, 0);
+ svc_wake_up(block->b_daemon);
+ rc = 0;
+ break;
+ }
+ }
+ unlock_kernel();
+ if (rc == -ENOENT)
+ printk(KERN_WARNING "lockd: grant for unknown block\n");
+ return rc;
}
/*
static void
nlmsvc_notify_blocked(struct file_lock *fl)
{
- struct nlm_block **bp, *block;
+ struct nlm_block *block;
dprintk("lockd: VFS unblock notification for block %p\n", fl);
- for (bp = &nlm_blocked; (block = *bp) != 0; bp = &block->b_next) {
- if (nlm_compare_locks(&block->b_call.a_args.lock.fl, fl)) {
+ 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);
svc_wake_up(block->b_daemon);
return;
return fl1->fl_owner == fl2->fl_owner && fl1->fl_pid == fl2->fl_pid;
}
-struct lock_manager_operations nlmsvc_lock_operations = {
+const struct lock_manager_operations nlmsvc_lock_operations = {
.fl_compare_owner = nlmsvc_same_owner,
.fl_notify = nlmsvc_notify_blocked,
+ .fl_grant = nlmsvc_grant_deferred,
};
/*
nlmsvc_grant_blocked(struct nlm_block *block)
{
struct nlm_file *file = block->b_file;
- struct nlm_lock *lock = &block->b_call.a_args.lock;
- struct file_lock *conflock;
+ struct nlm_lock *lock = &block->b_call->a_args.lock;
int error;
dprintk("lockd: grant blocked lock %p\n", block);
- /* First thing is lock the file */
- down(&file->f_sema);
+ kref_get(&block->b_count);
/* Unlink block request from list */
- nlmsvc_remove_block(block);
+ nlmsvc_unlink_block(block);
/* If b_granted is true this means we've been here before.
* Just retry the grant callback, possibly refreshing the RPC
}
/* Try the lock operation again */
- if ((conflock = posix_test_lock(file->f_file, &lock->fl)) != NULL) {
- /* Bummer, we blocked again */
- dprintk("lockd: lock still blocked\n");
+ 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) {
+ case 0:
+ break;
+ case FILE_LOCK_DEFERRED:
+ dprintk("lockd: lock still blocked error %d\n", error);
nlmsvc_insert_block(block, NLM_NEVER);
- posix_block_lock(conflock, &lock->fl);
- up(&file->f_sema);
+ nlmsvc_release_block(block);
return;
- }
-
- /* Alright, no conflicting lock. Now lock it for real. If the
- * following yields an error, this is most probably due to low
- * memory. Retry the lock in a few seconds.
- */
- if ((error = posix_lock_file(file->f_file, &lock->fl)) < 0) {
+ default:
printk(KERN_WARNING "lockd: unexpected error %d in %s!\n",
- -error, __FUNCTION__);
+ -error, __func__);
nlmsvc_insert_block(block, 10 * HZ);
- up(&file->f_sema);
+ nlmsvc_release_block(block);
return;
}
/* Lock was granted by VFS. */
dprintk("lockd: GRANTing blocked lock.\n");
block->b_granted = 1;
- block->b_incall = 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 */
- nlm_get_host(block->b_call.a_host);
- if (nlmsvc_async_call(&block->b_call, NLMPROC_GRANTED_MSG,
- nlmsvc_grant_callback) < 0)
- nlm_release_host(block->b_call.a_host);
- up(&file->f_sema);
+ /* 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);
+
+ /* RPC submission failed, wait a bit and retry */
+ if (error < 0)
+ nlmsvc_insert_block(block, 10 * HZ);
}
/*
* chain once more in order to have it removed by lockd itself (which can
* then sleep on the file semaphore without disrupting e.g. the nfs client).
*/
-static void
-nlmsvc_grant_callback(struct rpc_task *task)
+static void nlmsvc_grant_callback(struct rpc_task *task, void *data)
{
- struct nlm_rqst *call = (struct nlm_rqst *) task->tk_calldata;
- struct nlm_block *block;
+ struct nlm_rqst *call = data;
+ struct nlm_block *block = call->a_block;
unsigned long timeout;
- struct sockaddr_in *peer_addr = RPC_PEERADDR(task->tk_client);
dprintk("lockd: GRANT_MSG RPC callback\n");
- dprintk("callback: looking for cookie %s, host (%u.%u.%u.%u)\n",
- nlmdbg_cookie2a(&call->a_args.cookie),
- NIPQUAD(peer_addr->sin_addr.s_addr));
- if (!(block = nlmsvc_find_block(&call->a_args.cookie, peer_addr))) {
- dprintk("lockd: no block for cookie %s, host (%u.%u.%u.%u)\n",
- nlmdbg_cookie2a(&call->a_args.cookie),
- NIPQUAD(peer_addr->sin_addr.s_addr));
- return;
- }
+
+ lock_kernel();
+ /* 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
if (task->tk_status < 0) {
/* RPC error: Re-insert for retransmission */
timeout = 10 * HZ;
- } else if (block->b_done) {
- /* Block already removed, kill it for real */
- timeout = 0;
} else {
/* Call was successful, now wait for client callback */
timeout = 60 * HZ;
}
nlmsvc_insert_block(block, timeout);
svc_wake_up(block->b_daemon);
- block->b_incall = 0;
+out:
+ unlock_kernel();
+}
+
+static void nlmsvc_grant_release(void *data)
+{
+ struct nlm_rqst *call = data;
- nlm_release_host(call->a_host);
+ lock_kernel();
+ nlmsvc_release_block(call->a_block);
+ unlock_kernel();
}
+static const struct rpc_call_ops nlmsvc_grant_ops = {
+ .rpc_call_done = nlmsvc_grant_callback,
+ .rpc_release = nlmsvc_grant_release,
+};
+
/*
* We received a GRANT_RES callback. Try to find the corresponding
* block.
*/
void
-nlmsvc_grant_reply(struct svc_rqst *rqstp, struct nlm_cookie *cookie, u32 status)
+nlmsvc_grant_reply(struct nlm_cookie *cookie, __be32 status)
{
struct nlm_block *block;
- struct nlm_file *file;
- dprintk("grant_reply: looking for cookie %x, host (%08x), s=%d \n",
- *(unsigned int *)(cookie->data),
- ntohl(rqstp->rq_addr.sin_addr.s_addr), status);
- if (!(block = nlmsvc_find_block(cookie, &rqstp->rq_addr)))
+ dprintk("grant_reply: looking for cookie %x, s=%d \n",
+ *(unsigned int *)(cookie->data), status);
+ if (!(block = nlmsvc_find_block(cookie)))
return;
- file = block->b_file;
- file->f_count++;
- down(&file->f_sema);
- if ((block = nlmsvc_find_block(cookie,&rqstp->rq_addr)) != NULL) {
- if (status == NLM_LCK_DENIED_GRACE_PERIOD) {
+ if (block) {
+ if (status == nlm_lck_denied_grace_period) {
/* Try again in a couple of seconds */
nlmsvc_insert_block(block, 10 * HZ);
- block = NULL;
} else {
/* Lock is now held by client, or has been rejected.
* In both cases, the block should be removed. */
- up(&file->f_sema);
- if (status == NLM_LCK_GRANTED)
- nlmsvc_delete_block(block, 0);
- else
- nlmsvc_delete_block(block, 1);
+ nlmsvc_unlink_block(block);
}
}
- if (!block)
- up(&file->f_sema);
- nlm_release_file(file);
+ nlmsvc_release_block(block);
+}
+
+/* Helper function to handle retry of a deferred block.
+ * If it is a blocking lock, call grant_blocked.
+ * For a non-blocking lock or test lock, revisit the request.
+ */
+static void
+retry_deferred_block(struct nlm_block *block)
+{
+ if (!(block->b_flags & B_GOT_CALLBACK))
+ block->b_flags |= B_TIMED_OUT;
+ nlmsvc_insert_block(block, NLM_TIMEOUT);
+ dprintk("revisit block %p flags %d\n", block, block->b_flags);
+ if (block->b_deferred_req) {
+ block->b_deferred_req->revisit(block->b_deferred_req, 0);
+ block->b_deferred_req = NULL;
+ }
}
/*
unsigned long
nlmsvc_retry_blocked(void)
{
- struct nlm_block *block;
+ unsigned long timeout = MAX_SCHEDULE_TIMEOUT;
+ struct nlm_block *block;
+
+ while (!list_empty(&nlm_blocked) && !kthread_should_stop()) {
+ block = list_entry(nlm_blocked.next, struct nlm_block, b_list);
- dprintk("nlmsvc_retry_blocked(%p, when=%ld)\n",
- nlm_blocked,
- nlm_blocked? nlm_blocked->b_when : 0);
- while ((block = nlm_blocked) != 0) {
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;
- dprintk("nlmsvc_retry_blocked(%p, when=%ld, done=%d)\n",
- block, block->b_when, block->b_done);
- if (block->b_done)
- nlmsvc_delete_block(block, 0);
- else
+ }
+
+ dprintk("nlmsvc_retry_blocked(%p, when=%ld)\n",
+ block, block->b_when);
+ if (block->b_flags & B_QUEUED) {
+ dprintk("nlmsvc_retry_blocked delete block (%p, granted=%d, flags=%d)\n",
+ block, block->b_granted, block->b_flags);
+ retry_deferred_block(block);
+ } else
nlmsvc_grant_blocked(block);
}
- if ((block = nlm_blocked) && block->b_when != NLM_NEVER)
- return (block->b_when - jiffies);
-
- return MAX_SCHEDULE_TIMEOUT;
+ return timeout;
}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff