#include <linux/pid_namespace.h>
#include <linux/hashtable.h>
#include <linux/percpu.h>
-#include <linux/lglock.h>
#define CREATE_TRACE_POINTS
#include <trace/events/filelock.h>
#define IS_LEASE(fl) (fl->fl_flags & (FL_LEASE|FL_DELEG|FL_LAYOUT))
#define IS_OFDLCK(fl) (fl->fl_flags & FL_OFDLCK)
+static inline bool is_remote_lock(struct file *filp)
+{
+ return likely(!(filp->f_path.dentry->d_sb->s_flags & MS_NOREMOTELOCK));
+}
+
static bool lease_breaking(struct file_lock *fl)
{
return fl->fl_flags & (FL_UNLOCK_PENDING | FL_DOWNGRADE_PENDING);
/*
* The global file_lock_list is only used for displaying /proc/locks, so we
- * keep a list on each CPU, with each list protected by its own spinlock via
- * the file_lock_lglock. Note that alterations to the list also require that
- * the relevant flc_lock is held.
+ * keep a list on each CPU, with each list protected by its own spinlock.
+ * Global serialization is done using file_rwsem.
+ *
+ * Note that alterations to the list also require that the relevant flc_lock is
+ * held.
*/
-DEFINE_STATIC_LGLOCK(file_lock_lglock);
-static DEFINE_PER_CPU(struct hlist_head, file_lock_list);
+struct file_lock_list_struct {
+ spinlock_t lock;
+ struct hlist_head hlist;
+};
+static DEFINE_PER_CPU(struct file_lock_list_struct, file_lock_list);
+DEFINE_STATIC_PERCPU_RWSEM(file_rwsem);
/*
* The blocked_hash is used to find POSIX lock loops for deadlock detection.
/* Must be called with the flc_lock held! */
static void locks_insert_global_locks(struct file_lock *fl)
{
- lg_local_lock(&file_lock_lglock);
+ struct file_lock_list_struct *fll = this_cpu_ptr(&file_lock_list);
+
+ percpu_rwsem_assert_held(&file_rwsem);
+
+ spin_lock(&fll->lock);
fl->fl_link_cpu = smp_processor_id();
- hlist_add_head(&fl->fl_link, this_cpu_ptr(&file_lock_list));
- lg_local_unlock(&file_lock_lglock);
+ hlist_add_head(&fl->fl_link, &fll->hlist);
+ spin_unlock(&fll->lock);
}
/* Must be called with the flc_lock held! */
static void locks_delete_global_locks(struct file_lock *fl)
{
+ struct file_lock_list_struct *fll;
+
+ percpu_rwsem_assert_held(&file_rwsem);
+
/*
* Avoid taking lock if already unhashed. This is safe since this check
* is done while holding the flc_lock, and new insertions into the list
*/
if (hlist_unhashed(&fl->fl_link))
return;
- lg_local_lock_cpu(&file_lock_lglock, fl->fl_link_cpu);
+
+ fll = per_cpu_ptr(&file_lock_list, fl->fl_link_cpu);
+ spin_lock(&fll->lock);
hlist_del_init(&fl->fl_link);
- lg_local_unlock_cpu(&file_lock_lglock, fl->fl_link_cpu);
+ spin_unlock(&fll->lock);
}
static unsigned long
{
struct file_lock *cfl;
struct file_lock_context *ctx;
- struct inode *inode = file_inode(filp);
+ struct inode *inode = locks_inode(filp);
ctx = smp_load_acquire(&inode->i_flctx);
if (!ctx || list_empty_careful(&ctx->flc_posix)) {
return -ENOMEM;
}
+ percpu_down_read_preempt_disable(&file_rwsem);
spin_lock(&ctx->flc_lock);
if (request->fl_flags & FL_ACCESS)
goto find_conflict;
out:
spin_unlock(&ctx->flc_lock);
+ percpu_up_read_preempt_enable(&file_rwsem);
if (new_fl)
locks_free_lock(new_fl);
locks_dispose_list(&dispose);
new_fl2 = locks_alloc_lock();
}
+ percpu_down_read_preempt_disable(&file_rwsem);
spin_lock(&ctx->flc_lock);
/*
* New lock request. Walk all POSIX locks and look for conflicts. If
}
out:
spin_unlock(&ctx->flc_lock);
+ percpu_up_read_preempt_enable(&file_rwsem);
/*
* Free any unused locks.
*/
int posix_lock_file(struct file *filp, struct file_lock *fl,
struct file_lock *conflock)
{
- return posix_lock_inode(file_inode(filp), fl, conflock);
+ return posix_lock_inode(locks_inode(filp), fl, conflock);
}
EXPORT_SYMBOL(posix_lock_file);
int locks_mandatory_locked(struct file *file)
{
int ret;
- struct inode *inode = file_inode(file);
+ struct inode *inode = locks_inode(file);
struct file_lock_context *ctx;
struct file_lock *fl;
return error;
}
+ percpu_down_read_preempt_disable(&file_rwsem);
spin_lock(&ctx->flc_lock);
time_out_leases(inode, &dispose);
locks_insert_block(fl, new_fl);
trace_break_lease_block(inode, new_fl);
spin_unlock(&ctx->flc_lock);
+ percpu_up_read_preempt_enable(&file_rwsem);
+
locks_dispose_list(&dispose);
error = wait_event_interruptible_timeout(new_fl->fl_wait,
!new_fl->fl_next, break_time);
+
+ percpu_down_read_preempt_disable(&file_rwsem);
spin_lock(&ctx->flc_lock);
trace_break_lease_unblock(inode, new_fl);
locks_delete_block(new_fl);
}
out:
spin_unlock(&ctx->flc_lock);
+ percpu_up_read_preempt_enable(&file_rwsem);
locks_dispose_list(&dispose);
locks_free_lock(new_fl);
return error;
int fcntl_getlease(struct file *filp)
{
struct file_lock *fl;
- struct inode *inode = file_inode(filp);
+ struct inode *inode = locks_inode(filp);
struct file_lock_context *ctx;
int type = F_UNLCK;
LIST_HEAD(dispose);
ctx = smp_load_acquire(&inode->i_flctx);
if (ctx && !list_empty_careful(&ctx->flc_lease)) {
spin_lock(&ctx->flc_lock);
- time_out_leases(file_inode(filp), &dispose);
+ time_out_leases(inode, &dispose);
list_for_each_entry(fl, &ctx->flc_lease, fl_list) {
if (fl->fl_file != filp)
continue;
if (flags & FL_LAYOUT)
return 0;
- if ((arg == F_RDLCK) && (atomic_read(&inode->i_writecount) > 0))
+ if ((arg == F_RDLCK) &&
+ (atomic_read(&d_real_inode(dentry)->i_writecount) > 0))
return -EAGAIN;
if ((arg == F_WRLCK) && ((d_count(dentry) > 1) ||
{
struct file_lock *fl, *my_fl = NULL, *lease;
struct dentry *dentry = filp->f_path.dentry;
- struct inode *inode = file_inode(filp);
+ struct inode *inode = dentry->d_inode;
struct file_lock_context *ctx;
bool is_deleg = (*flp)->fl_flags & FL_DELEG;
int error;
return -EINVAL;
}
+ percpu_down_read_preempt_disable(&file_rwsem);
spin_lock(&ctx->flc_lock);
time_out_leases(inode, &dispose);
error = check_conflicting_open(dentry, arg, lease->fl_flags);
lease->fl_lmops->lm_setup(lease, priv);
out:
spin_unlock(&ctx->flc_lock);
+ percpu_up_read_preempt_enable(&file_rwsem);
locks_dispose_list(&dispose);
if (is_deleg)
inode_unlock(inode);
{
int error = -EAGAIN;
struct file_lock *fl, *victim = NULL;
- struct inode *inode = file_inode(filp);
+ struct inode *inode = locks_inode(filp);
struct file_lock_context *ctx;
LIST_HEAD(dispose);
return error;
}
+ percpu_down_read_preempt_disable(&file_rwsem);
spin_lock(&ctx->flc_lock);
list_for_each_entry(fl, &ctx->flc_lease, fl_list) {
if (fl->fl_file == filp &&
if (victim)
error = fl->fl_lmops->lm_change(victim, F_UNLCK, &dispose);
spin_unlock(&ctx->flc_lock);
+ percpu_up_read_preempt_enable(&file_rwsem);
locks_dispose_list(&dispose);
return error;
}
int generic_setlease(struct file *filp, long arg, struct file_lock **flp,
void **priv)
{
- struct inode *inode = file_inode(filp);
+ struct inode *inode = locks_inode(filp);
int error;
if ((!uid_eq(current_fsuid(), inode->i_uid)) && !capable(CAP_LEASE))
int
vfs_setlease(struct file *filp, long arg, struct file_lock **lease, void **priv)
{
- if (filp->f_op->setlease)
+ if (filp->f_op->setlease && is_remote_lock(filp))
return filp->f_op->setlease(filp, arg, lease, priv);
else
return generic_setlease(filp, arg, lease, priv);
if (error)
goto out_free;
- if (f.file->f_op->flock)
+ if (f.file->f_op->flock && is_remote_lock(f.file))
error = f.file->f_op->flock(f.file,
(can_sleep) ? F_SETLKW : F_SETLK,
lock);
*/
int vfs_test_lock(struct file *filp, struct file_lock *fl)
{
- if (filp->f_op->lock)
+ if (filp->f_op->lock && is_remote_lock(filp))
return filp->f_op->lock(filp, F_GETLK, fl);
posix_test_lock(filp, fl);
return 0;
*/
int vfs_lock_file(struct file *filp, unsigned int cmd, struct file_lock *fl, struct file_lock *conf)
{
- if (filp->f_op->lock)
+ if (filp->f_op->lock && is_remote_lock(filp))
return filp->f_op->lock(filp, cmd, fl);
else
return posix_lock_file(filp, fl, conf);
if (file_lock == NULL)
return -ENOLCK;
- inode = file_inode(filp);
+ inode = locks_inode(filp);
/*
* This might block, so we do it before checking the inode.
if (copy_from_user(&flock, l, sizeof(flock)))
goto out;
- inode = file_inode(filp);
+ inode = locks_inode(filp);
/* Don't allow mandatory locks on files that may be memory mapped
* and shared.
void locks_remove_posix(struct file *filp, fl_owner_t owner)
{
int error;
+ struct inode *inode = locks_inode(filp);
struct file_lock lock;
struct file_lock_context *ctx;
* posix_lock_file(). Another process could be setting a lock on this
* file at the same time, but we wouldn't remove that lock anyway.
*/
- ctx = smp_load_acquire(&file_inode(filp)->i_flctx);
+ ctx = smp_load_acquire(&inode->i_flctx);
if (!ctx || list_empty(&ctx->flc_posix))
return;
if (lock.fl_ops && lock.fl_ops->fl_release_private)
lock.fl_ops->fl_release_private(&lock);
- trace_locks_remove_posix(file_inode(filp), &lock, error);
+ trace_locks_remove_posix(inode, &lock, error);
}
EXPORT_SYMBOL(locks_remove_posix);
.fl_type = F_UNLCK,
.fl_end = OFFSET_MAX,
};
- struct inode *inode = file_inode(filp);
+ struct inode *inode = locks_inode(filp);
if (list_empty(&flctx->flc_flock))
return;
- if (filp->f_op->flock)
+ if (filp->f_op->flock && is_remote_lock(filp))
filp->f_op->flock(filp, F_SETLKW, &fl);
else
flock_lock_inode(inode, &fl);
{
struct file_lock_context *ctx;
- ctx = smp_load_acquire(&file_inode(filp)->i_flctx);
+ ctx = smp_load_acquire(&locks_inode(filp)->i_flctx);
if (!ctx)
return;
*/
int vfs_cancel_lock(struct file *filp, struct file_lock *fl)
{
- if (filp->f_op->lock)
+ if (filp->f_op->lock && is_remote_lock(filp))
return filp->f_op->lock(filp, F_CANCELLK, fl);
return 0;
}
struct inode *inode = NULL;
unsigned int fl_pid;
- if (fl->fl_nspid)
- fl_pid = pid_vnr(fl->fl_nspid);
- else
+ if (fl->fl_nspid) {
+ struct pid_namespace *proc_pidns = file_inode(f->file)->i_sb->s_fs_info;
+
+ /* Don't let fl_pid change based on who is reading the file */
+ fl_pid = pid_nr_ns(fl->fl_nspid, proc_pidns);
+
+ /*
+ * If there isn't a fl_pid don't display who is waiting on
+ * the lock if we are called from locks_show, or if we are
+ * called from __show_fd_info - skip lock entirely
+ */
+ if (fl_pid == 0)
+ return;
+ } else
fl_pid = fl->fl_pid;
if (fl->fl_file != NULL)
- inode = file_inode(fl->fl_file);
+ inode = locks_inode(fl->fl_file);
seq_printf(f, "%lld:%s ", id, pfx);
if (IS_POSIX(fl)) {
{
struct locks_iterator *iter = f->private;
struct file_lock *fl, *bfl;
+ struct pid_namespace *proc_pidns = file_inode(f->file)->i_sb->s_fs_info;
fl = hlist_entry(v, struct file_lock, fl_link);
+ if (fl->fl_nspid && !pid_nr_ns(fl->fl_nspid, proc_pidns))
+ return 0;
+
lock_get_status(f, fl, iter->li_pos, "");
list_for_each_entry(bfl, &fl->fl_block, fl_block)
void show_fd_locks(struct seq_file *f,
struct file *filp, struct files_struct *files)
{
- struct inode *inode = file_inode(filp);
+ struct inode *inode = locks_inode(filp);
struct file_lock_context *ctx;
int id = 0;
struct locks_iterator *iter = f->private;
iter->li_pos = *pos + 1;
- lg_global_lock(&file_lock_lglock);
+ percpu_down_write(&file_rwsem);
spin_lock(&blocked_lock_lock);
- return seq_hlist_start_percpu(&file_lock_list, &iter->li_cpu, *pos);
+ return seq_hlist_start_percpu(&file_lock_list.hlist, &iter->li_cpu, *pos);
}
static void *locks_next(struct seq_file *f, void *v, loff_t *pos)
struct locks_iterator *iter = f->private;
++iter->li_pos;
- return seq_hlist_next_percpu(v, &file_lock_list, &iter->li_cpu, pos);
+ return seq_hlist_next_percpu(v, &file_lock_list.hlist, &iter->li_cpu, pos);
}
static void locks_stop(struct seq_file *f, void *v)
__releases(&blocked_lock_lock)
{
spin_unlock(&blocked_lock_lock);
- lg_global_unlock(&file_lock_lglock);
+ percpu_up_write(&file_rwsem);
}
static const struct seq_operations locks_seq_operations = {
filelock_cache = kmem_cache_create("file_lock_cache",
sizeof(struct file_lock), 0, SLAB_PANIC, NULL);
- lg_lock_init(&file_lock_lglock, "file_lock_lglock");
- for_each_possible_cpu(i)
- INIT_HLIST_HEAD(per_cpu_ptr(&file_lock_list, i));
+ for_each_possible_cpu(i) {
+ struct file_lock_list_struct *fll = per_cpu_ptr(&file_lock_list, i);
+
+ spin_lock_init(&fll->lock);
+ INIT_HLIST_HEAD(&fll->hlist);
+ }
return 0;
}
projects / cascardo / linux.git / blobdiff