static struct kmem_cache *filelock_cache __read_mostly;
static struct file_lock_context *
-locks_get_lock_context(struct inode *inode)
+locks_get_lock_context(struct inode *inode, int type)
{
struct file_lock_context *new;
- if (likely(inode->i_flctx))
+ if (likely(inode->i_flctx) || type == F_UNLCK)
goto out;
new = kmem_cache_alloc(flctx_cache, GFP_KERNEL);
* Assign the pointer if it's not already assigned. If it is, then
* free the context we just allocated.
*/
- spin_lock(&inode->i_lock);
- if (likely(!inode->i_flctx)) {
- inode->i_flctx = new;
- new = NULL;
- }
- spin_unlock(&inode->i_lock);
-
- if (new)
+ if (cmpxchg(&inode->i_flctx, NULL, new))
kmem_cache_free(flctx_cache, new);
out:
return inode->i_flctx;
}
if (fl->fl_lmops) {
- if (fl->fl_lmops->lm_put_owner)
- fl->fl_lmops->lm_put_owner(fl);
+ if (fl->fl_lmops->lm_put_owner) {
+ fl->fl_lmops->lm_put_owner(fl->fl_owner);
+ fl->fl_owner = NULL;
+ }
fl->fl_lmops = NULL;
}
}
if (fl->fl_lmops) {
if (fl->fl_lmops->lm_get_owner)
- fl->fl_lmops->lm_get_owner(new, fl);
+ fl->fl_lmops->lm_get_owner(fl->fl_owner);
}
}
EXPORT_SYMBOL(locks_copy_conflock);
static void locks_insert_global_blocked(struct file_lock *waiter)
{
+ lockdep_assert_held(&blocked_lock_lock);
+
hash_add(blocked_hash, &waiter->fl_link, posix_owner_key(waiter));
}
static void locks_delete_global_blocked(struct file_lock *waiter)
{
+ lockdep_assert_held(&blocked_lock_lock);
+
hash_del(&waiter->fl_link);
}
/* POSIX locks owned by the same process do not conflict with
* each other.
*/
- if (!IS_POSIX(sys_fl) || posix_same_owner(caller_fl, sys_fl))
+ if (posix_same_owner(caller_fl, sys_fl))
return (0);
/* Check whether they overlap */
/* FLOCK locks referring to the same filp do not conflict with
* each other.
*/
- if (!IS_FLOCK(sys_fl) || (caller_fl->fl_file == sys_fl->fl_file))
+ if (caller_fl->fl_file == sys_fl->fl_file)
return (0);
if ((caller_fl->fl_type & LOCK_MAND) || (sys_fl->fl_type & LOCK_MAND))
return 0;
{
int i = 0;
+ lockdep_assert_held(&blocked_lock_lock);
+
/*
* This deadlock detector can't reasonably detect deadlocks with
* FL_OFDLCK locks, since they aren't owned by a process, per-se.
* whether or not a lock was successfully freed by testing the return
* value for -ENOENT.
*/
-static int flock_lock_file(struct file *filp, struct file_lock *request)
+static int flock_lock_inode(struct inode *inode, struct file_lock *request)
{
struct file_lock *new_fl = NULL;
struct file_lock *fl;
struct file_lock_context *ctx;
- struct inode *inode = file_inode(filp);
int error = 0;
bool found = false;
LIST_HEAD(dispose);
- ctx = locks_get_lock_context(inode);
- if (!ctx)
- return -ENOMEM;
+ ctx = locks_get_lock_context(inode, request->fl_type);
+ if (!ctx) {
+ if (request->fl_type != F_UNLCK)
+ return -ENOMEM;
+ return (request->fl_flags & FL_EXISTS) ? -ENOENT : 0;
+ }
if (!(request->fl_flags & FL_ACCESS) && (request->fl_type != F_UNLCK)) {
new_fl = locks_alloc_lock();
goto find_conflict;
list_for_each_entry(fl, &ctx->flc_flock, fl_list) {
- if (filp != fl->fl_file)
+ if (request->fl_file != fl->fl_file)
continue;
if (request->fl_type == fl->fl_type)
goto out;
bool added = false;
LIST_HEAD(dispose);
- ctx = locks_get_lock_context(inode);
+ ctx = locks_get_lock_context(inode, request->fl_type);
if (!ctx)
- return -ENOMEM;
+ return (request->fl_type == F_UNLCK) ? 0 : -ENOMEM;
/*
* We may need two file_lock structures for this operation,
*/
if (request->fl_type != F_UNLCK) {
list_for_each_entry(fl, &ctx->flc_posix, fl_list) {
- if (!IS_POSIX(fl))
- continue;
if (!posix_locks_conflict(request, fl))
continue;
if (conflock)
EXPORT_SYMBOL(posix_lock_file);
/**
- * posix_lock_file_wait - Apply a POSIX-style lock to a file
- * @filp: The file to apply the lock to
+ * posix_lock_inode_wait - Apply a POSIX-style lock to a file
+ * @inode: inode of file to which lock request should be applied
* @fl: The lock to be applied
*
- * Add a POSIX style lock to a file.
- * We merge adjacent & overlapping locks whenever possible.
- * POSIX locks are sorted by owner task, then by starting address
+ * Variant of posix_lock_file_wait that does not take a filp, and so can be
+ * used after the filp has already been torn down.
*/
-int posix_lock_file_wait(struct file *filp, struct file_lock *fl)
+int posix_lock_inode_wait(struct inode *inode, struct file_lock *fl)
{
int error;
might_sleep ();
for (;;) {
- error = posix_lock_file(filp, fl, NULL);
+ error = __posix_lock_file(inode, fl, NULL);
if (error != FILE_LOCK_DEFERRED)
break;
error = wait_event_interruptible(fl->fl_wait, !fl->fl_next);
}
return error;
}
-EXPORT_SYMBOL(posix_lock_file_wait);
+EXPORT_SYMBOL(posix_lock_inode_wait);
/**
* locks_mandatory_locked - Check for an active lock
lease = *flp;
trace_generic_add_lease(inode, lease);
- ctx = locks_get_lock_context(inode);
+ /* Note that arg is never F_UNLCK here */
+ ctx = locks_get_lock_context(inode, arg);
if (!ctx)
return -ENOMEM;
}
/**
- * flock_lock_file_wait - Apply a FLOCK-style lock to a file
- * @filp: The file to apply the lock to
+ * flock_lock_inode_wait - Apply a FLOCK-style lock to a file
+ * @inode: inode of the file to apply to
* @fl: The lock to be applied
*
- * Add a FLOCK style lock to a file.
+ * Apply a FLOCK style lock request to an inode.
*/
-int flock_lock_file_wait(struct file *filp, struct file_lock *fl)
+int flock_lock_inode_wait(struct inode *inode, struct file_lock *fl)
{
int error;
might_sleep();
for (;;) {
- error = flock_lock_file(filp, fl);
+ error = flock_lock_inode(inode, fl);
if (error != FILE_LOCK_DEFERRED)
break;
error = wait_event_interruptible(fl->fl_wait, !fl->fl_next);
}
return error;
}
-
-EXPORT_SYMBOL(flock_lock_file_wait);
+EXPORT_SYMBOL(flock_lock_inode_wait);
/**
* sys_flock: - flock() system call.
.fl_type = F_UNLCK,
.fl_end = OFFSET_MAX,
};
- struct file_lock_context *flctx = file_inode(filp)->i_flctx;
+ struct inode *inode = file_inode(filp);
+ struct file_lock_context *flctx = inode->i_flctx;
if (list_empty(&flctx->flc_flock))
return;
if (filp->f_op->flock)
filp->f_op->flock(filp, F_SETLKW, &fl);
else
- flock_lock_file(filp, &fl);
+ flock_lock_inode(inode, &fl);
if (fl.fl_ops && fl.fl_ops->fl_release_private)
fl.fl_ops->fl_release_private(&fl);
: (fl->fl_type == F_WRLCK) ? "WRITE" : "READ ");
}
if (inode) {
-#ifdef WE_CAN_BREAK_LSLK_NOW
- seq_printf(f, "%d %s:%ld ", fl_pid,
- inode->i_sb->s_id, inode->i_ino);
-#else
- /* userspace relies on this representation of dev_t ;-( */
+ /* userspace relies on this representation of dev_t */
seq_printf(f, "%d %02x:%02x:%ld ", fl_pid,
MAJOR(inode->i_sb->s_dev),
MINOR(inode->i_sb->s_dev), inode->i_ino);
-#endif
} else {
seq_printf(f, "%d <none>:0 ", fl_pid);
}
return 0;
}
+static void __show_fd_locks(struct seq_file *f,
+ struct list_head *head, int *id,
+ struct file *filp, struct files_struct *files)
+{
+ struct file_lock *fl;
+
+ list_for_each_entry(fl, head, fl_list) {
+
+ if (filp != fl->fl_file)
+ continue;
+ if (fl->fl_owner != files &&
+ fl->fl_owner != filp)
+ continue;
+
+ (*id)++;
+ seq_puts(f, "lock:\t");
+ lock_get_status(f, fl, *id, "");
+ }
+}
+
+void show_fd_locks(struct seq_file *f,
+ struct file *filp, struct files_struct *files)
+{
+ struct inode *inode = file_inode(filp);
+ struct file_lock_context *ctx;
+ int id = 0;
+
+ ctx = inode->i_flctx;
+ if (!ctx)
+ return;
+
+ spin_lock(&ctx->flc_lock);
+ __show_fd_locks(f, &ctx->flc_flock, &id, filp, files);
+ __show_fd_locks(f, &ctx->flc_posix, &id, filp, files);
+ __show_fd_locks(f, &ctx->flc_lease, &id, filp, files);
+ spin_unlock(&ctx->flc_lock);
+}
+
static void *locks_start(struct seq_file *f, loff_t *pos)
__acquires(&blocked_lock_lock)
{