}
/* Fill in a file_lock structure with an appropriate FLOCK lock. */
-static int flock_make_lock(struct file *filp, struct file_lock **lock,
- unsigned int cmd)
+static struct file_lock *
+flock_make_lock(struct file *filp, unsigned int cmd)
{
struct file_lock *fl;
int type = flock_translate_cmd(cmd);
+
if (type < 0)
- return type;
+ return ERR_PTR(type);
fl = locks_alloc_lock();
if (fl == NULL)
- return -ENOMEM;
+ return ERR_PTR(-ENOMEM);
fl->fl_file = filp;
fl->fl_owner = filp;
fl->fl_type = type;
fl->fl_end = OFFSET_MAX;
- *lock = fl;
- return 0;
+ return fl;
}
static int assign_type(struct file_lock *fl, long type)
}
/* default lease lock manager operations */
-static void lease_break_callback(struct file_lock *fl)
+static bool
+lease_break_callback(struct file_lock *fl)
{
kill_fasync(&fl->fl_fasync, SIGIO, POLL_MSG);
+ return false;
+}
+
+static void
+lease_setup(struct file_lock *fl, void **priv)
+{
+ struct file *filp = fl->fl_file;
+ struct fasync_struct *fa = *priv;
+
+ /*
+ * fasync_insert_entry() returns the old entry if any. If there was no
+ * old entry, then it used "priv" and inserted it into the fasync list.
+ * Clear the pointer to indicate that it shouldn't be freed.
+ */
+ if (!fasync_insert_entry(fa->fa_fd, filp, &fl->fl_fasync, fa))
+ *priv = NULL;
+
+ __f_setown(filp, task_pid(current), PIDTYPE_PID, 0);
}
static const struct lock_manager_operations lease_manager_ops = {
.lm_break = lease_break_callback,
.lm_change = lease_modify,
+ .lm_setup = lease_setup,
};
/*
if (assign_type(fl, type) != 0)
return -EINVAL;
- fl->fl_owner = current->files;
+ fl->fl_owner = filp;
fl->fl_pid = current->tgid;
fl->fl_file = filp;
}
/* We already had a lease on this file; just change its type */
-int lease_modify(struct file_lock **before, int arg)
+int lease_modify(struct file_lock **before, int arg, struct list_head *dispose)
{
struct file_lock *fl = *before;
int error = assign_type(fl, arg);
printk(KERN_ERR "locks_delete_lock: fasync == %p\n", fl->fl_fasync);
fl->fl_fasync = NULL;
}
- locks_delete_lock(before, NULL);
+ locks_delete_lock(before, dispose);
}
return 0;
}
-
EXPORT_SYMBOL(lease_modify);
static bool past_time(unsigned long then)
return time_after(jiffies, then);
}
-static void time_out_leases(struct inode *inode)
+static void time_out_leases(struct inode *inode, struct list_head *dispose)
{
struct file_lock **before;
struct file_lock *fl;
+ lockdep_assert_held(&inode->i_lock);
+
before = &inode->i_flock;
while ((fl = *before) && IS_LEASE(fl) && lease_breaking(fl)) {
trace_time_out_leases(inode, fl);
if (past_time(fl->fl_downgrade_time))
- lease_modify(before, F_RDLCK);
+ lease_modify(before, F_RDLCK, dispose);
if (past_time(fl->fl_break_time))
- lease_modify(before, F_UNLCK);
+ lease_modify(before, F_UNLCK, dispose);
if (fl == *before) /* lease_modify may have freed fl */
before = &fl->fl_next;
}
return locks_conflict(breaker, lease);
}
+static bool
+any_leases_conflict(struct inode *inode, struct file_lock *breaker)
+{
+ struct file_lock *fl;
+
+ lockdep_assert_held(&inode->i_lock);
+
+ for (fl = inode->i_flock ; fl && IS_LEASE(fl); fl = fl->fl_next) {
+ if (leases_conflict(fl, breaker))
+ return true;
+ }
+ return false;
+}
+
/**
* __break_lease - revoke all outstanding leases on file
* @inode: the inode of the file to return
int __break_lease(struct inode *inode, unsigned int mode, unsigned int type)
{
int error = 0;
- struct file_lock *new_fl, *flock;
- struct file_lock *fl;
+ struct file_lock *new_fl;
+ struct file_lock *fl, **before;
unsigned long break_time;
- int i_have_this_lease = 0;
- bool lease_conflict = false;
int want_write = (mode & O_ACCMODE) != O_RDONLY;
+ LIST_HEAD(dispose);
new_fl = lease_alloc(NULL, want_write ? F_WRLCK : F_RDLCK);
if (IS_ERR(new_fl))
spin_lock(&inode->i_lock);
- time_out_leases(inode);
+ time_out_leases(inode, &dispose);
- flock = inode->i_flock;
- if ((flock == NULL) || !IS_LEASE(flock))
- goto out;
-
- for (fl = flock; fl && IS_LEASE(fl); fl = fl->fl_next) {
- if (leases_conflict(fl, new_fl)) {
- lease_conflict = true;
- if (fl->fl_owner == current->files)
- i_have_this_lease = 1;
- }
- }
- if (!lease_conflict)
+ if (!any_leases_conflict(inode, new_fl))
goto out;
break_time = 0;
break_time++; /* so that 0 means no break time */
}
- for (fl = flock; fl && IS_LEASE(fl); fl = fl->fl_next) {
+ for (before = &inode->i_flock;
+ ((fl = *before) != NULL) && IS_LEASE(fl);
+ before = &fl->fl_next) {
if (!leases_conflict(fl, new_fl))
continue;
if (want_write) {
fl->fl_flags |= FL_UNLOCK_PENDING;
fl->fl_break_time = break_time;
} else {
- if (lease_breaking(flock))
+ if (lease_breaking(inode->i_flock))
continue;
fl->fl_flags |= FL_DOWNGRADE_PENDING;
fl->fl_downgrade_time = break_time;
}
- fl->fl_lmops->lm_break(fl);
+ if (fl->fl_lmops->lm_break(fl))
+ locks_delete_lock(before, &dispose);
}
- if (i_have_this_lease || (mode & O_NONBLOCK)) {
+ fl = inode->i_flock;
+ if (!fl || !IS_LEASE(fl))
+ goto out;
+
+ if (mode & O_NONBLOCK) {
trace_break_lease_noblock(inode, new_fl);
error = -EWOULDBLOCK;
goto out;
}
restart:
- break_time = flock->fl_break_time;
+ break_time = inode->i_flock->fl_break_time;
if (break_time != 0)
break_time -= jiffies;
if (break_time == 0)
break_time++;
- locks_insert_block(flock, new_fl);
+ locks_insert_block(inode->i_flock, new_fl);
trace_break_lease_block(inode, new_fl);
spin_unlock(&inode->i_lock);
+ locks_dispose_list(&dispose);
error = wait_event_interruptible_timeout(new_fl->fl_wait,
!new_fl->fl_next, break_time);
spin_lock(&inode->i_lock);
trace_break_lease_unblock(inode, new_fl);
locks_delete_block(new_fl);
if (error >= 0) {
- if (error == 0)
- time_out_leases(inode);
/*
* Wait for the next conflicting lease that has not been
* broken yet
*/
- for (flock = inode->i_flock; flock && IS_LEASE(flock);
- flock = flock->fl_next) {
- if (leases_conflict(new_fl, flock))
- goto restart;
- }
+ if (error == 0)
+ time_out_leases(inode, &dispose);
+ if (any_leases_conflict(inode, new_fl))
+ goto restart;
+
error = 0;
}
out:
spin_unlock(&inode->i_lock);
+ locks_dispose_list(&dispose);
locks_free_lock(new_fl);
return error;
}
struct file_lock *fl;
struct inode *inode = file_inode(filp);
int type = F_UNLCK;
+ LIST_HEAD(dispose);
spin_lock(&inode->i_lock);
- time_out_leases(file_inode(filp));
+ time_out_leases(file_inode(filp), &dispose);
for (fl = file_inode(filp)->i_flock; fl && IS_LEASE(fl);
fl = fl->fl_next) {
if (fl->fl_file == filp) {
}
}
spin_unlock(&inode->i_lock);
+ locks_dispose_list(&dispose);
return type;
}
return ret;
}
-static int generic_add_lease(struct file *filp, long arg, struct file_lock **flp)
+static int
+generic_add_lease(struct file *filp, long arg, struct file_lock **flp, void **priv)
{
struct file_lock *fl, **before, **my_before = NULL, *lease;
struct dentry *dentry = filp->f_path.dentry;
struct inode *inode = dentry->d_inode;
bool is_deleg = (*flp)->fl_flags & FL_DELEG;
int error;
+ LIST_HEAD(dispose);
lease = *flp;
trace_generic_add_lease(inode, lease);
return -EINVAL;
}
+ spin_lock(&inode->i_lock);
+ time_out_leases(inode, &dispose);
error = check_conflicting_open(dentry, arg);
if (error)
goto out;
}
if (my_before != NULL) {
- error = lease->fl_lmops->lm_change(my_before, arg);
- if (!error)
- *flp = *my_before;
- goto out;
+ lease = *my_before;
+ error = lease->fl_lmops->lm_change(my_before, arg, &dispose);
+ if (error)
+ goto out;
+ goto out_setup;
}
error = -EINVAL;
smp_mb();
error = check_conflicting_open(dentry, arg);
if (error)
- locks_unlink_lock(before);
+ goto out_unlink;
+
+out_setup:
+ if (lease->fl_lmops->lm_setup)
+ lease->fl_lmops->lm_setup(lease, priv);
out:
+ spin_unlock(&inode->i_lock);
+ locks_dispose_list(&dispose);
if (is_deleg)
mutex_unlock(&inode->i_mutex);
+ if (!error && !my_before)
+ *flp = NULL;
return error;
+out_unlink:
+ locks_unlink_lock(before);
+ goto out;
}
-static int generic_delete_lease(struct file *filp, struct file_lock **flp)
+static int generic_delete_lease(struct file *filp)
{
+ int error = -EAGAIN;
struct file_lock *fl, **before;
struct dentry *dentry = filp->f_path.dentry;
struct inode *inode = dentry->d_inode;
+ LIST_HEAD(dispose);
- trace_generic_delete_lease(inode, *flp);
-
+ spin_lock(&inode->i_lock);
+ time_out_leases(inode, &dispose);
for (before = &inode->i_flock;
((fl = *before) != NULL) && IS_LEASE(fl);
before = &fl->fl_next) {
- if (fl->fl_file != filp)
- continue;
- return (*flp)->fl_lmops->lm_change(before, F_UNLCK);
+ if (fl->fl_file == filp)
+ break;
}
- return -EAGAIN;
+ trace_generic_delete_lease(inode, fl);
+ if (fl)
+ error = fl->fl_lmops->lm_change(before, F_UNLCK, &dispose);
+ spin_unlock(&inode->i_lock);
+ locks_dispose_list(&dispose);
+ return error;
}
/**
* generic_setlease - sets a lease on an open file
- * @filp: file pointer
- * @arg: type of lease to obtain
- * @flp: input - file_lock to use, output - file_lock inserted
+ * @filp: file pointer
+ * @arg: type of lease to obtain
+ * @flp: input - file_lock to use, output - file_lock inserted
+ * @priv: private data for lm_setup (may be NULL if lm_setup
+ * doesn't require it)
*
* The (input) flp->fl_lmops->lm_break function is required
* by break_lease().
- *
- * Called with inode->i_lock held.
*/
-int generic_setlease(struct file *filp, long arg, struct file_lock **flp)
+int generic_setlease(struct file *filp, long arg, struct file_lock **flp,
+ void **priv)
{
struct dentry *dentry = filp->f_path.dentry;
struct inode *inode = dentry->d_inode;
if (error)
return error;
- time_out_leases(inode);
-
- BUG_ON(!(*flp)->fl_lmops->lm_break);
-
switch (arg) {
case F_UNLCK:
- return generic_delete_lease(filp, flp);
+ return generic_delete_lease(filp);
case F_RDLCK:
case F_WRLCK:
- return generic_add_lease(filp, arg, flp);
+ if (!(*flp)->fl_lmops->lm_break) {
+ WARN_ON_ONCE(1);
+ return -ENOLCK;
+ }
+ return generic_add_lease(filp, arg, flp, priv);
default:
return -EINVAL;
}
}
EXPORT_SYMBOL(generic_setlease);
-static int __vfs_setlease(struct file *filp, long arg, struct file_lock **lease)
-{
- if (filp->f_op->setlease)
- return filp->f_op->setlease(filp, arg, lease);
- else
- return generic_setlease(filp, arg, lease);
-}
-
/**
- * vfs_setlease - sets a lease on an open file
- * @filp: file pointer
- * @arg: type of lease to obtain
- * @lease: file_lock to use
- *
- * Call this to establish a lease on the file.
- * The (*lease)->fl_lmops->lm_break operation must be set; if not,
- * break_lease will oops!
- *
- * This will call the filesystem's setlease file method, if
- * defined. Note that there is no getlease method; instead, the
- * filesystem setlease method should call back to setlease() to
- * add a lease to the inode's lease list, where fcntl_getlease() can
- * find it. Since fcntl_getlease() only reports whether the current
- * task holds a lease, a cluster filesystem need only do this for
- * leases held by processes on this node.
- *
- * There is also no break_lease method; filesystems that
- * handle their own leases should break leases themselves from the
- * filesystem's open, create, and (on truncate) setattr methods.
- *
- * Warning: the only current setlease methods exist only to disable
- * leases in certain cases. More vfs changes may be required to
- * allow a full filesystem lease implementation.
+ * vfs_setlease - sets a lease on an open file
+ * @filp: file pointer
+ * @arg: type of lease to obtain
+ * @lease: file_lock to use when adding a lease
+ * @priv: private info for lm_setup when adding a lease (may be
+ * NULL if lm_setup doesn't require it)
+ *
+ * Call this to establish a lease on the file. The "lease" argument is not
+ * used for F_UNLCK requests and may be NULL. For commands that set or alter
+ * an existing lease, the (*lease)->fl_lmops->lm_break operation must be set;
+ * if not, this function will return -ENOLCK (and generate a scary-looking
+ * stack trace).
+ *
+ * The "priv" pointer is passed directly to the lm_setup function as-is. It
+ * may be NULL if the lm_setup operation doesn't require it.
*/
-
-int vfs_setlease(struct file *filp, long arg, struct file_lock **lease)
+int
+vfs_setlease(struct file *filp, long arg, struct file_lock **lease, void **priv)
{
- struct inode *inode = file_inode(filp);
- int error;
-
- spin_lock(&inode->i_lock);
- error = __vfs_setlease(filp, arg, lease);
- spin_unlock(&inode->i_lock);
-
- return error;
+ if (filp->f_op->setlease)
+ return filp->f_op->setlease(filp, arg, lease, priv);
+ else
+ return generic_setlease(filp, arg, lease, priv);
}
EXPORT_SYMBOL_GPL(vfs_setlease);
-static int do_fcntl_delete_lease(struct file *filp)
-{
- struct file_lock fl, *flp = &fl;
-
- lease_init(filp, F_UNLCK, flp);
-
- return vfs_setlease(filp, F_UNLCK, &flp);
-}
-
static int do_fcntl_add_lease(unsigned int fd, struct file *filp, long arg)
{
- struct file_lock *fl, *ret;
- struct inode *inode = file_inode(filp);
+ struct file_lock *fl;
struct fasync_struct *new;
int error;
locks_free_lock(fl);
return -ENOMEM;
}
- ret = fl;
- spin_lock(&inode->i_lock);
- error = __vfs_setlease(filp, arg, &ret);
- if (error)
- goto out_unlock;
- if (ret == fl)
- fl = NULL;
+ new->fa_fd = fd;
- /*
- * fasync_insert_entry() returns the old entry if any.
- * If there was no old entry, then it used 'new' and
- * inserted it into the fasync list. Clear new so that
- * we don't release it here.
- */
- if (!fasync_insert_entry(fd, filp, &ret->fl_fasync, new))
- new = NULL;
-
- __f_setown(filp, task_pid(current), PIDTYPE_PID, 0);
-out_unlock:
- spin_unlock(&inode->i_lock);
+ error = vfs_setlease(filp, arg, &fl, (void **)&new);
if (fl)
locks_free_lock(fl);
if (new)
int fcntl_setlease(unsigned int fd, struct file *filp, long arg)
{
if (arg == F_UNLCK)
- return do_fcntl_delete_lease(filp);
+ return vfs_setlease(filp, F_UNLCK, NULL, NULL);
return do_fcntl_add_lease(fd, filp, arg);
}
!(f.file->f_mode & (FMODE_READ|FMODE_WRITE)))
goto out_putf;
- error = flock_make_lock(f.file, &lock, cmd);
- if (error)
+ lock = flock_make_lock(f.file, cmd);
+ if (IS_ERR(lock)) {
+ error = PTR_ERR(lock);
goto out_putf;
+ }
+
if (can_sleep)
lock->fl_flags |= FL_SLEEP;
while ((fl = *before) != NULL) {
if (fl->fl_file == filp) {
if (IS_LEASE(fl)) {
- lease_modify(before, F_UNLCK);
+ lease_modify(before, F_UNLCK, &dispose);
continue;
}
git.openpandora.org / pandora-kernel.git / blobdiff