#include <linux/security.h>
#include <linux/slab.h>
#include <linux/smp_lock.h>
+#include <linux/syscalls.h>
#include <linux/time.h>
+#include <linux/rcupdate.h>
+#include <linux/vs_base.h>
+#include <linux/vs_limit.h>
#include <asm/semaphore.h>
#include <asm/uaccess.h>
#define for_each_lock(inode, lockp) \
for (lockp = &inode->i_flock; *lockp != NULL; lockp = &(*lockp)->fl_next)
-LIST_HEAD(file_lock_list);
-
-EXPORT_SYMBOL(file_lock_list);
-
+static LIST_HEAD(file_lock_list);
static LIST_HEAD(blocked_list);
-static kmem_cache_t *filelock_cache;
+static struct kmem_cache *filelock_cache __read_mostly;
/* Allocate an empty lock structure. */
static struct file_lock *locks_alloc_lock(void)
{
- return kmem_cache_alloc(filelock_cache, SLAB_KERNEL);
+ if (!vx_locks_avail(1))
+ return NULL;
+ return kmem_cache_alloc(filelock_cache, GFP_KERNEL);
}
-/* Free a lock which is not in use. */
-static inline void locks_free_lock(struct file_lock *fl)
+static void locks_release_private(struct file_lock *fl)
{
- if (fl == NULL) {
- BUG();
- return;
- }
- if (waitqueue_active(&fl->fl_wait))
- panic("Attempting to free lock with active wait queue");
-
- if (!list_empty(&fl->fl_block))
- panic("Attempting to free lock with active block list");
-
- if (!list_empty(&fl->fl_link))
- panic("Attempting to free lock on active lock list");
-
if (fl->fl_ops) {
if (fl->fl_ops->fl_release_private)
fl->fl_ops->fl_release_private(fl);
fl->fl_ops = NULL;
}
- fl->fl_lmops = NULL;
+ if (fl->fl_lmops) {
+ if (fl->fl_lmops->fl_release_private)
+ fl->fl_lmops->fl_release_private(fl);
+ fl->fl_lmops = NULL;
+ }
+}
+
+/* Free a lock which is not in use. */
+static void locks_free_lock(struct file_lock *fl)
+{
+ BUG_ON(waitqueue_active(&fl->fl_wait));
+ BUG_ON(!list_empty(&fl->fl_block));
+ BUG_ON(!list_empty(&fl->fl_link));
+
+ vx_locks_dec(fl);
+ locks_release_private(fl);
kmem_cache_free(filelock_cache, fl);
}
fl->fl_start = fl->fl_end = 0;
fl->fl_ops = NULL;
fl->fl_lmops = NULL;
+ fl->fl_xid = -1;
}
EXPORT_SYMBOL(locks_init_lock);
* Initialises the fields of the file lock which are invariant for
* free file_locks.
*/
-static void init_once(void *foo, kmem_cache_t *cache, unsigned long flags)
+static void init_once(void *foo, struct kmem_cache *cache, unsigned long flags)
{
struct file_lock *lock = (struct file_lock *) foo;
locks_init_lock(lock);
}
+static void locks_copy_private(struct file_lock *new, struct file_lock *fl)
+{
+ if (fl->fl_ops) {
+ if (fl->fl_ops->fl_copy_lock)
+ fl->fl_ops->fl_copy_lock(new, fl);
+ new->fl_ops = fl->fl_ops;
+ }
+ if (fl->fl_lmops) {
+ if (fl->fl_lmops->fl_copy_lock)
+ fl->fl_lmops->fl_copy_lock(new, fl);
+ new->fl_lmops = fl->fl_lmops;
+ }
+}
+
/*
* Initialize a new lock from an existing file_lock structure.
*/
-void locks_copy_lock(struct file_lock *new, struct file_lock *fl)
+static void __locks_copy_lock(struct file_lock *new, const struct file_lock *fl)
{
new->fl_owner = fl->fl_owner;
new->fl_pid = fl->fl_pid;
- new->fl_file = fl->fl_file;
+ new->fl_file = NULL;
new->fl_flags = fl->fl_flags;
new->fl_type = fl->fl_type;
new->fl_start = fl->fl_start;
new->fl_end = fl->fl_end;
+ new->fl_ops = NULL;
+ new->fl_lmops = NULL;
+}
+
+void locks_copy_lock(struct file_lock *new, struct file_lock *fl)
+{
+ locks_release_private(new);
+
+ __locks_copy_lock(new, fl);
+ new->fl_file = fl->fl_file;
new->fl_ops = fl->fl_ops;
new->fl_lmops = fl->fl_lmops;
- if (fl->fl_ops && fl->fl_ops->fl_copy_lock)
- fl->fl_ops->fl_copy_lock(new, fl);
+ new->fl_xid = fl->fl_xid;
+
+ locks_copy_private(new, fl);
}
EXPORT_SYMBOL(locks_copy_lock);
fl->fl_flags = FL_FLOCK;
fl->fl_type = type;
fl->fl_end = OFFSET_MAX;
+
+ vxd_assert(filp->f_xid == vx_current_xid(),
+ "f_xid(%d) == current(%d)", filp->f_xid, vx_current_xid());
+ fl->fl_xid = filp->f_xid;
+ vx_locks_inc(fl);
*lock = fl;
return 0;
off_t start, end;
switch (l->l_whence) {
- case 0: /*SEEK_SET*/
+ case SEEK_SET:
start = 0;
break;
- case 1: /*SEEK_CUR*/
+ case SEEK_CUR:
start = filp->f_pos;
break;
- case 2: /*SEEK_END*/
- start = i_size_read(filp->f_dentry->d_inode);
+ case SEEK_END:
+ start = i_size_read(filp->f_path.dentry->d_inode);
break;
default:
return -EINVAL;
/* POSIX-1996 leaves the case l->l_len < 0 undefined;
POSIX-2001 defines it. */
start += l->l_start;
- end = start + l->l_len - 1;
- if (l->l_len < 0) {
+ if (start < 0)
+ return -EINVAL;
+ fl->fl_end = OFFSET_MAX;
+ if (l->l_len > 0) {
+ end = start + l->l_len - 1;
+ fl->fl_end = end;
+ } else if (l->l_len < 0) {
end = start - 1;
+ fl->fl_end = end;
start += l->l_len;
+ if (start < 0)
+ return -EINVAL;
}
-
- if (start < 0)
- return -EINVAL;
- if (l->l_len > 0 && end < 0)
- return -EOVERFLOW;
-
fl->fl_start = start; /* we record the absolute position */
- fl->fl_end = end;
- if (l->l_len == 0)
- fl->fl_end = OFFSET_MAX;
+ if (fl->fl_end < fl->fl_start)
+ return -EOVERFLOW;
fl->fl_owner = current->files;
fl->fl_pid = current->tgid;
loff_t start;
switch (l->l_whence) {
- case 0: /*SEEK_SET*/
+ case SEEK_SET:
start = 0;
break;
- case 1: /*SEEK_CUR*/
+ case SEEK_CUR:
start = filp->f_pos;
break;
- case 2: /*SEEK_END*/
- start = i_size_read(filp->f_dentry->d_inode);
+ case SEEK_END:
+ start = i_size_read(filp->f_path.dentry->d_inode);
break;
default:
return -EINVAL;
}
- if (((start += l->l_start) < 0) || (l->l_len < 0))
+ start += l->l_start;
+ if (start < 0)
return -EINVAL;
- fl->fl_end = start + l->l_len - 1;
- if (l->l_len > 0 && fl->fl_end < 0)
- return -EOVERFLOW;
+ fl->fl_end = OFFSET_MAX;
+ if (l->l_len > 0) {
+ fl->fl_end = start + l->l_len - 1;
+ } else if (l->l_len < 0) {
+ fl->fl_end = start - 1;
+ start += l->l_len;
+ if (start < 0)
+ return -EINVAL;
+ }
fl->fl_start = start; /* we record the absolute position */
- if (l->l_len == 0)
- fl->fl_end = OFFSET_MAX;
+ if (fl->fl_end < fl->fl_start)
+ return -EOVERFLOW;
fl->fl_owner = current->files;
fl->fl_pid = current->tgid;
}
#endif
-/* Allocate a file_lock initialised to this type of lease */
-static int lease_alloc(struct file *filp, int type, struct file_lock **flp)
+/* default lease lock manager operations */
+static void lease_break_callback(struct file_lock *fl)
{
- struct file_lock *fl = locks_alloc_lock();
- if (fl == NULL)
- return -ENOMEM;
+ kill_fasync(&fl->fl_fasync, SIGIO, POLL_MSG);
+}
+
+static void lease_release_private_callback(struct file_lock *fl)
+{
+ if (!fl->fl_file)
+ return;
+
+ f_delown(fl->fl_file);
+ fl->fl_file->f_owner.signum = 0;
+}
+
+static int lease_mylease_callback(struct file_lock *fl, struct file_lock *try)
+{
+ return fl->fl_file == try->fl_file;
+}
+
+static struct lock_manager_operations lease_manager_ops = {
+ .fl_break = lease_break_callback,
+ .fl_release_private = lease_release_private_callback,
+ .fl_mylease = lease_mylease_callback,
+ .fl_change = lease_modify,
+};
+
+/*
+ * Initialize a lease, use the default lock manager operations
+ */
+static int lease_init(struct file *filp, int type, struct file_lock *fl)
+ {
+ if (assign_type(fl, type) != 0)
+ return -EINVAL;
fl->fl_owner = current->files;
fl->fl_pid = current->tgid;
+ fl->fl_xid = vx_current_xid();
fl->fl_file = filp;
fl->fl_flags = FL_LEASE;
- if (assign_type(fl, type) != 0) {
- locks_free_lock(fl);
- return -EINVAL;
- }
fl->fl_start = 0;
fl->fl_end = OFFSET_MAX;
fl->fl_ops = NULL;
- fl->fl_lmops = NULL;
+ fl->fl_lmops = &lease_manager_ops;
+ return 0;
+}
+
+/* Allocate a file_lock initialised to this type of lease */
+static int lease_alloc(struct file *filp, int type, struct file_lock **flp)
+{
+ struct file_lock *fl = locks_alloc_lock();
+ int error = -ENOMEM;
+
+ if (fl == NULL)
+ goto out;
+ fl->fl_xid = vx_current_xid();
+ if (filp)
+ vxd_assert(filp->f_xid == fl->fl_xid,
+ "f_xid(%d) == fl_xid(%d)", filp->f_xid, fl->fl_xid);
+ vx_locks_inc(fl);
+ error = lease_init(filp, type, fl);
+ if (error) {
+ locks_free_lock(fl);
+ fl = NULL;
+ }
+out:
*flp = fl;
- return 0;
+ return error;
}
/* Check if two locks overlap each other.
/*
* Check whether two locks have the same owner.
*/
-static inline int
-posix_same_owner(struct file_lock *fl1, struct file_lock *fl2)
+static int posix_same_owner(struct file_lock *fl1, struct file_lock *fl2)
{
if (fl1->fl_lmops && fl1->fl_lmops->fl_compare_owner)
return fl2->fl_lmops == fl1->fl_lmops &&
/* Remove waiter from blocker's block list.
* When blocker ends up pointing to itself then the list is empty.
*/
-static inline void __locks_delete_block(struct file_lock *waiter)
+static void __locks_delete_block(struct file_lock *waiter)
{
list_del_init(&waiter->fl_block);
list_del_init(&waiter->fl_link);
static void locks_insert_block(struct file_lock *blocker,
struct file_lock *waiter)
{
- if (!list_empty(&waiter->fl_block)) {
- printk(KERN_ERR "locks_insert_block: removing duplicated lock "
- "(pid=%d %Ld-%Ld type=%d)\n", waiter->fl_pid,
- waiter->fl_start, waiter->fl_end, waiter->fl_type);
- __locks_delete_block(waiter);
- }
+ BUG_ON(!list_empty(&waiter->fl_block));
list_add_tail(&waiter->fl_block, &blocker->fl_block);
waiter->fl_next = blocker;
if (IS_POSIX(blocker))
return result;
}
-struct file_lock *
-posix_test_lock(struct file *filp, struct file_lock *fl)
+int
+posix_test_lock(struct file *filp, struct file_lock *fl,
+ struct file_lock *conflock)
{
struct file_lock *cfl;
lock_kernel();
- for (cfl = filp->f_dentry->d_inode->i_flock; cfl; cfl = cfl->fl_next) {
+ for (cfl = filp->f_path.dentry->d_inode->i_flock; cfl; cfl = cfl->fl_next) {
if (!IS_POSIX(cfl))
continue;
if (posix_locks_conflict(cfl, fl))
break;
}
+ if (cfl) {
+ __locks_copy_lock(conflock, cfl);
+ unlock_kernel();
+ return 1;
+ }
unlock_kernel();
-
- return (cfl);
+ return 0;
}
EXPORT_SYMBOL(posix_test_lock);
* from a broken NFS client. But broken NFS clients have a lot more to
* worry about than proper deadlock detection anyway... --okir
*/
-int posix_locks_deadlock(struct file_lock *caller_fl,
+static int posix_locks_deadlock(struct file_lock *caller_fl,
struct file_lock *block_fl)
{
struct list_head *tmp;
return 0;
}
-EXPORT_SYMBOL(posix_locks_deadlock);
-
/* Try to create a FLOCK lock on filp. We always insert new FLOCK locks
* at the head of the list, but that's secret knowledge known only to
* flock_lock_file and posix_lock_file.
+ *
+ * Note that if called with an FL_EXISTS argument, the caller may determine
+ * 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 *new_fl)
+static int flock_lock_file(struct file *filp, struct file_lock *request)
{
+ struct file_lock *new_fl = NULL;
struct file_lock **before;
- struct inode * inode = filp->f_dentry->d_inode;
+ struct inode * inode = filp->f_path.dentry->d_inode;
int error = 0;
int found = 0;
lock_kernel();
+ if (request->fl_flags & FL_ACCESS)
+ goto find_conflict;
for_each_lock(inode, before) {
struct file_lock *fl = *before;
if (IS_POSIX(fl))
continue;
if (filp != fl->fl_file)
continue;
- if (new_fl->fl_type == fl->fl_type)
+ if (request->fl_type == fl->fl_type)
goto out;
found = 1;
locks_delete_lock(before);
break;
}
- unlock_kernel();
- if (new_fl->fl_type == F_UNLCK)
- return 0;
+ if (request->fl_type == F_UNLCK) {
+ if ((request->fl_flags & FL_EXISTS) && !found)
+ error = -ENOENT;
+ goto out;
+ }
+ error = -ENOMEM;
+ new_fl = locks_alloc_lock();
+ if (new_fl == NULL)
+ goto out;
/*
* If a higher-priority process was blocked on the old file lock,
* give it the opportunity to lock the file.
if (found)
cond_resched();
- lock_kernel();
+ new_fl->fl_xid = -1;
+find_conflict:
for_each_lock(inode, before) {
struct file_lock *fl = *before;
if (IS_POSIX(fl))
break;
if (IS_LEASE(fl))
continue;
- if (!flock_locks_conflict(new_fl, fl))
+ if (!flock_locks_conflict(request, fl))
continue;
error = -EAGAIN;
- if (new_fl->fl_flags & FL_SLEEP) {
- locks_insert_block(fl, new_fl);
- }
+ if (request->fl_flags & FL_SLEEP)
+ locks_insert_block(fl, request);
goto out;
}
+ if (request->fl_flags & FL_ACCESS)
+ goto out;
+ locks_copy_lock(new_fl, request);
locks_insert_lock(&inode->i_flock, new_fl);
+ vx_locks_inc(new_fl);
+ new_fl = NULL;
error = 0;
out:
unlock_kernel();
+ if (new_fl)
+ locks_free_lock(new_fl);
return error;
}
-EXPORT_SYMBOL(posix_lock_file);
-
-static int __posix_lock_file(struct inode *inode, struct file_lock *request)
+static int __posix_lock_file_conf(struct inode *inode, struct file_lock *request,
+ struct file_lock *conflock, xid_t xid)
{
struct file_lock *fl;
- struct file_lock *new_fl, *new_fl2;
+ struct file_lock *new_fl = NULL;
+ struct file_lock *new_fl2 = NULL;
struct file_lock *left = NULL;
struct file_lock *right = NULL;
struct file_lock **before;
int error, added = 0;
+ vxd_assert(xid == vx_current_xid(),
+ "xid(%d) == current(%d)", xid, vx_current_xid());
/*
* We may need two file_lock structures for this operation,
* so we get them in advance to avoid races.
+ *
+ * In some cases we can be sure, that no new locks will be needed
*/
- new_fl = locks_alloc_lock();
- new_fl2 = locks_alloc_lock();
+ if (!(request->fl_flags & FL_ACCESS) &&
+ (request->fl_type != F_UNLCK ||
+ request->fl_start != 0 || request->fl_end != OFFSET_MAX)) {
+ new_fl = locks_alloc_lock();
+ new_fl->fl_xid = xid;
+ vx_locks_inc(new_fl);
+ new_fl2 = locks_alloc_lock();
+ new_fl2->fl_xid = xid;
+ vx_locks_inc(new_fl2);
+ }
lock_kernel();
if (request->fl_type != F_UNLCK) {
continue;
if (!posix_locks_conflict(request, fl))
continue;
+ if (conflock)
+ locks_copy_lock(conflock, fl);
error = -EAGAIN;
if (!(request->fl_flags & FL_SLEEP))
goto out;
if (request->fl_flags & FL_ACCESS)
goto out;
- error = -ENOLCK; /* "no luck" */
- if (!(new_fl && new_fl2))
- goto out;
-
/*
- * We've allocated the new locks in advance, so there are no
- * errors possible (and no blocking operations) from here on.
- *
* Find the first old lock with the same owner as the new lock.
*/
/* Detect adjacent or overlapping regions (if same lock type)
*/
if (request->fl_type == fl->fl_type) {
+ /* In all comparisons of start vs end, use
+ * "start - 1" rather than "end + 1". If end
+ * is OFFSET_MAX, end + 1 will become negative.
+ */
if (fl->fl_end < request->fl_start - 1)
goto next_lock;
/* If the next lock in the list has entirely bigger
* addresses than the new one, insert the lock here.
*/
- if (fl->fl_start > request->fl_end + 1)
+ if (fl->fl_start - 1 > request->fl_end)
break;
/* If we come here, the new and old lock are of the
fl->fl_start = request->fl_start;
fl->fl_end = request->fl_end;
fl->fl_type = request->fl_type;
- fl->fl_u = request->fl_u;
+ locks_release_private(fl);
+ locks_copy_private(fl, request);
request = fl;
added = 1;
}
before = &fl->fl_next;
}
+ /*
+ * The above code only modifies existing locks in case of
+ * merging or replacing. If new lock(s) need to be inserted
+ * all modifications are done bellow this, so it's safe yet to
+ * bail out.
+ */
+ error = -ENOLCK; /* "no luck" */
+ if (right && left == right && !new_fl2)
+ goto out;
+
error = 0;
if (!added) {
- if (request->fl_type == F_UNLCK)
+ if (request->fl_type == F_UNLCK) {
+ if (request->fl_flags & FL_EXISTS)
+ error = -ENOENT;
goto out;
+ }
+
+ if (!new_fl) {
+ error = -ENOLCK;
+ goto out;
+ }
locks_copy_lock(new_fl, request);
locks_insert_lock(before, new_fl);
new_fl = NULL;
* 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
+ *
+ * Note that if called with an FL_EXISTS argument, the caller may determine
+ * whether or not a lock was successfully freed by testing the return
+ * value for -ENOENT.
*/
int posix_lock_file(struct file *filp, struct file_lock *fl)
{
- return __posix_lock_file(filp->f_dentry->d_inode, fl);
+ return __posix_lock_file_conf(filp->f_path.dentry->d_inode,
+ fl, NULL, filp->f_xid);
+}
+EXPORT_SYMBOL(posix_lock_file);
+
+/**
+ * posix_lock_file_conf - Apply a POSIX-style lock to a file
+ * @filp: The file to apply the lock to
+ * @fl: The lock to be applied
+ * @conflock: Place to return a copy of the conflicting lock, if found.
+ *
+ * Except for the conflock parameter, acts just like posix_lock_file.
+ */
+int posix_lock_file_conf(struct file *filp, struct file_lock *fl,
+ struct file_lock *conflock)
+{
+ return __posix_lock_file_conf(filp->f_path.dentry->d_inode,
+ fl, conflock, filp->f_xid);
}
+EXPORT_SYMBOL(posix_lock_file_conf);
/**
* posix_lock_file_wait - Apply a POSIX-style lock to a file
int error;
might_sleep ();
for (;;) {
- error = __posix_lock_file(filp->f_dentry->d_inode, fl);
+ error = posix_lock_file(filp, fl);
if ((error != -EAGAIN) || !(fl->fl_flags & FL_SLEEP))
break;
error = wait_event_interruptible(fl->fl_wait, !fl->fl_next);
* @count: length of area to check
*
* Searches the inode's list of locks to find any POSIX locks which conflict.
- * This function is called from locks_verify_area() and
+ * This function is called from rw_verify_area() and
* locks_verify_truncate().
*/
int locks_mandatory_area(int read_write, struct inode *inode,
fl.fl_end = offset + count - 1;
for (;;) {
- error = __posix_lock_file(inode, &fl);
+ error = __posix_lock_file_conf(inode, &fl, NULL, filp->f_xid);
if (error != -EAGAIN)
break;
if (!(fl.fl_flags & FL_SLEEP))
EXPORT_SYMBOL(locks_mandatory_area);
/* We already had a lease on this file; just change its type */
-static int lease_modify(struct file_lock **before, int arg)
+int lease_modify(struct file_lock **before, int arg)
{
struct file_lock *fl = *before;
int error = assign_type(fl, arg);
if (error)
return error;
locks_wake_up_blocks(fl);
- if (arg == F_UNLCK) {
- struct file *filp = fl->fl_file;
-
- f_delown(filp);
- filp->f_owner.signum = 0;
+ if (arg == F_UNLCK)
locks_delete_lock(before);
- }
return 0;
}
+EXPORT_SYMBOL(lease_modify);
+
static void time_out_leases(struct inode *inode)
{
struct file_lock **before;
before = &fl->fl_next;
continue;
}
- printk(KERN_INFO "lease broken - owner pid = %d\n", fl->fl_pid);
lease_modify(before, fl->fl_type & ~F_INPROGRESS);
if (fl == *before) /* lease_modify may have freed fl */
before = &fl->fl_next;
if (fl->fl_type != future) {
fl->fl_type = future;
fl->fl_break_time = break_time;
- kill_fasync(&fl->fl_fasync, SIGIO, POLL_MSG);
+ /* lease must have lmops break callback */
+ fl->fl_lmops->fl_break(fl);
}
}
{
struct file_lock *flock = inode->i_flock;
if (flock && IS_LEASE(flock) && (flock->fl_type & F_WRLCK))
- *time = CURRENT_TIME;
+ *time = current_fs_time(inode->i_sb);
else
*time = inode->i_mtime;
}
int type = F_UNLCK;
lock_kernel();
- time_out_leases(filp->f_dentry->d_inode);
- for (fl = filp->f_dentry->d_inode->i_flock; fl && IS_LEASE(fl);
+ time_out_leases(filp->f_path.dentry->d_inode);
+ for (fl = filp->f_path.dentry->d_inode->i_flock; fl && IS_LEASE(fl);
fl = fl->fl_next) {
if (fl->fl_file == filp) {
type = fl->fl_type & ~F_INPROGRESS;
}
/**
- * fcntl_setlease - sets a lease on an open file
- * @fd: open file descriptor
+ * __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
*
- * Call this fcntl to establish a lease on the file.
- * Note that you also need to call %F_SETSIG to
- * receive a signal when the lease is broken.
+ * The (input) flp->fl_lmops->fl_break function is required
+ * by break_lease().
+ *
+ * Called with kernel lock held.
*/
-int fcntl_setlease(unsigned int fd, struct file *filp, long arg)
+static int __setlease(struct file *filp, long arg, struct file_lock **flp)
{
- struct file_lock *fl, **before, **my_before = NULL;
- struct dentry *dentry;
- struct inode *inode;
+ struct file_lock *fl, **before, **my_before = NULL, *lease;
+ struct dentry *dentry = filp->f_path.dentry;
+ struct inode *inode = dentry->d_inode;
int error, rdlease_count = 0, wrlease_count = 0;
- dentry = filp->f_dentry;
- inode = dentry->d_inode;
-
- if ((current->fsuid != inode->i_uid) && !capable(CAP_LEASE))
- return -EACCES;
- if (!S_ISREG(inode->i_mode))
- return -EINVAL;
- error = security_file_lock(filp, arg);
- if (error)
- return error;
+ time_out_leases(inode);
- lock_kernel();
+ error = -EINVAL;
+ if (!flp || !(*flp) || !(*flp)->fl_lmops || !(*flp)->fl_lmops->fl_break)
+ goto out;
- time_out_leases(inode);
+ lease = *flp;
- /*
- * FIXME: What about F_RDLCK and files open for writing?
- */
error = -EAGAIN;
+ if ((arg == F_RDLCK) && (atomic_read(&inode->i_writecount) > 0))
+ goto out;
if ((arg == F_WRLCK)
&& ((atomic_read(&dentry->d_count) > 1)
|| (atomic_read(&inode->i_count) > 1)))
- goto out_unlock;
+ goto out;
/*
* At this point, we know that if there is an exclusive
for (before = &inode->i_flock;
((fl = *before) != NULL) && IS_LEASE(fl);
before = &fl->fl_next) {
- if (fl->fl_file == filp)
+ if (lease->fl_lmops->fl_mylease(fl, lease))
my_before = before;
else if (fl->fl_type == (F_INPROGRESS | F_UNLCK))
/*
if ((arg == F_RDLCK && (wrlease_count > 0)) ||
(arg == F_WRLCK && ((rdlease_count + wrlease_count) > 0)))
- goto out_unlock;
+ goto out;
if (my_before != NULL) {
- error = lease_modify(my_before, arg);
- goto out_unlock;
+ *flp = *my_before;
+ error = lease->fl_lmops->fl_change(my_before, arg);
+ goto out;
}
error = 0;
if (arg == F_UNLCK)
- goto out_unlock;
+ goto out;
error = -EINVAL;
if (!leases_enable)
- goto out_unlock;
+ goto out;
+
+ error = -ENOMEM;
+ fl = locks_alloc_lock();
+ if (fl == NULL)
+ goto out;
+
+ locks_copy_lock(fl, lease);
+ locks_insert_lock(before, fl);
+ vx_locks_inc(fl);
+
+ *flp = fl;
+ error = 0;
+out:
+ return error;
+}
+
+ /**
+ * 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 fl_lmops fl_break function is required by break_lease
+ */
+
+int setlease(struct file *filp, long arg, struct file_lock **lease)
+{
+ struct dentry *dentry = filp->f_path.dentry;
+ struct inode *inode = dentry->d_inode;
+ int error;
+
+ if ((current->fsuid != inode->i_uid) && !capable(CAP_LEASE))
+ return -EACCES;
+ if (!S_ISREG(inode->i_mode))
+ return -EINVAL;
+ error = security_file_lock(filp, arg);
+ if (error)
+ return error;
+
+ lock_kernel();
+ error = __setlease(filp, arg, lease);
+ unlock_kernel();
+
+ return error;
+}
+
+EXPORT_SYMBOL(setlease);
+
+/**
+ * fcntl_setlease - sets a lease on an open file
+ * @fd: open file descriptor
+ * @filp: file pointer
+ * @arg: type of lease to obtain
+ *
+ * Call this fcntl to establish a lease on the file.
+ * Note that you also need to call %F_SETSIG to
+ * receive a signal when the lease is broken.
+ */
+int fcntl_setlease(unsigned int fd, struct file *filp, long arg)
+{
+ struct file_lock fl, *flp = &fl;
+ struct dentry *dentry = filp->f_path.dentry;
+ struct inode *inode = dentry->d_inode;
+ int error;
+
+ if ((current->fsuid != inode->i_uid) && !capable(CAP_LEASE))
+ return -EACCES;
+ if (!S_ISREG(inode->i_mode))
+ return -EINVAL;
+ error = security_file_lock(filp, arg);
+ if (error)
+ return error;
- error = lease_alloc(filp, arg, &fl);
+ locks_init_lock(&fl);
+ error = lease_init(filp, arg, &fl);
if (error)
+ return error;
+
+ lock_kernel();
+
+ error = __setlease(filp, arg, &flp);
+ if (error || arg == F_UNLCK)
goto out_unlock;
- error = fasync_helper(fd, filp, 1, &fl->fl_fasync);
+ error = fasync_helper(fd, filp, 1, &flp->fl_fasync);
if (error < 0) {
- locks_free_lock(fl);
+ /* remove lease just inserted by __setlease */
+ flp->fl_type = F_UNLCK | F_INPROGRESS;
+ flp->fl_break_time = jiffies- 10;
+ time_out_leases(inode);
goto out_unlock;
}
- locks_insert_lock(before, fl);
-
- error = f_setown(filp, current->pid, 0);
+ error = __f_setown(filp, task_pid(current), PIDTYPE_PID, 0);
out_unlock:
unlock_kernel();
return error;
error = flock_lock_file_wait(filp, lock);
out_free:
- if (list_empty(&lock->fl_link)) {
- locks_free_lock(lock);
- }
+ locks_free_lock(lock);
out_putf:
fput(filp);
*/
int fcntl_getlk(struct file *filp, struct flock __user *l)
{
- struct file_lock *fl, file_lock;
+ struct file_lock *fl, cfl, file_lock;
struct flock flock;
int error;
if (filp->f_op && filp->f_op->lock) {
error = filp->f_op->lock(filp, F_GETLK, &file_lock);
+ if (file_lock.fl_ops && file_lock.fl_ops->fl_release_private)
+ file_lock.fl_ops->fl_release_private(&file_lock);
if (error < 0)
goto out;
- else if (error == LOCK_USE_CLNT)
- /* Bypass for NFS with no locking - 2.0.36 compat */
- fl = posix_test_lock(filp, &file_lock);
else
fl = (file_lock.fl_type == F_UNLCK ? NULL : &file_lock);
} else {
- fl = posix_test_lock(filp, &file_lock);
+ fl = (posix_test_lock(filp, &file_lock, &cfl) ? &cfl : NULL);
}
flock.l_type = F_UNLCK;
/* Apply the lock described by l to an open file descriptor.
* This implements both the F_SETLK and F_SETLKW commands of fcntl().
*/
-int fcntl_setlk(struct file *filp, unsigned int cmd, struct flock __user *l)
+int fcntl_setlk(unsigned int fd, struct file *filp, unsigned int cmd,
+ struct flock __user *l)
{
struct file_lock *file_lock = locks_alloc_lock();
struct flock flock;
if (file_lock == NULL)
return -ENOLCK;
+ vxd_assert(filp->f_xid == vx_current_xid(),
+ "f_xid(%d) == current(%d)", filp->f_xid, vx_current_xid());
+ file_lock->fl_xid = filp->f_xid;
+ vx_locks_inc(file_lock);
+
/*
* This might block, so we do it before checking the inode.
*/
if (copy_from_user(&flock, l, sizeof(flock)))
goto out;
- inode = filp->f_dentry->d_inode;
+ inode = filp->f_path.dentry->d_inode;
/* Don't allow mandatory locks on files that may be memory mapped
* and shared.
goto out;
}
+again:
error = flock_to_posix_lock(filp, file_lock, &flock);
if (error)
goto out;
if (error)
goto out;
- if (filp->f_op && filp->f_op->lock != NULL) {
+ if (filp->f_op && filp->f_op->lock != NULL)
error = filp->f_op->lock(filp, cmd, file_lock);
- goto out;
- }
+ else {
+ for (;;) {
+ error = posix_lock_file(filp, file_lock);
+ if ((error != -EAGAIN) || (cmd == F_SETLK))
+ break;
+ error = wait_event_interruptible(file_lock->fl_wait,
+ !file_lock->fl_next);
+ if (!error)
+ continue;
- for (;;) {
- error = __posix_lock_file(inode, file_lock);
- if ((error != -EAGAIN) || (cmd == F_SETLK))
+ locks_delete_block(file_lock);
break;
- error = wait_event_interruptible(file_lock->fl_wait,
- !file_lock->fl_next);
- if (!error)
- continue;
+ }
+ }
- locks_delete_block(file_lock);
- break;
+ /*
+ * Attempt to detect a close/fcntl race and recover by
+ * releasing the lock that was just acquired.
+ */
+ if (!error && fcheck(fd) != filp && flock.l_type != F_UNLCK) {
+ flock.l_type = F_UNLCK;
+ goto again;
}
- out:
+out:
locks_free_lock(file_lock);
return error;
}
*/
int fcntl_getlk64(struct file *filp, struct flock64 __user *l)
{
- struct file_lock *fl, file_lock;
+ struct file_lock *fl, cfl, file_lock;
struct flock64 flock;
int error;
if (filp->f_op && filp->f_op->lock) {
error = filp->f_op->lock(filp, F_GETLK, &file_lock);
+ if (file_lock.fl_ops && file_lock.fl_ops->fl_release_private)
+ file_lock.fl_ops->fl_release_private(&file_lock);
if (error < 0)
goto out;
- else if (error == LOCK_USE_CLNT)
- /* Bypass for NFS with no locking - 2.0.36 compat */
- fl = posix_test_lock(filp, &file_lock);
else
fl = (file_lock.fl_type == F_UNLCK ? NULL : &file_lock);
} else {
- fl = posix_test_lock(filp, &file_lock);
+ fl = (posix_test_lock(filp, &file_lock, &cfl) ? &cfl : NULL);
}
flock.l_type = F_UNLCK;
/* Apply the lock described by l to an open file descriptor.
* This implements both the F_SETLK and F_SETLKW commands of fcntl().
*/
-int fcntl_setlk64(struct file *filp, unsigned int cmd, struct flock64 __user *l)
+int fcntl_setlk64(unsigned int fd, struct file *filp, unsigned int cmd,
+ struct flock64 __user *l)
{
struct file_lock *file_lock = locks_alloc_lock();
struct flock64 flock;
if (file_lock == NULL)
return -ENOLCK;
+ vxd_assert(filp->f_xid == vx_current_xid(),
+ "f_xid(%d) == current(%d)", filp->f_xid, vx_current_xid());
+ file_lock->fl_xid = filp->f_xid;
+ vx_locks_inc(file_lock);
+
/*
* This might block, so we do it before checking the inode.
*/
if (copy_from_user(&flock, l, sizeof(flock)))
goto out;
- inode = filp->f_dentry->d_inode;
+ inode = filp->f_path.dentry->d_inode;
/* Don't allow mandatory locks on files that may be memory mapped
* and shared.
goto out;
}
+again:
error = flock64_to_posix_lock(filp, file_lock, &flock);
if (error)
goto out;
if (error)
goto out;
- if (filp->f_op && filp->f_op->lock != NULL) {
+ if (filp->f_op && filp->f_op->lock != NULL)
error = filp->f_op->lock(filp, cmd, file_lock);
- goto out;
- }
+ else {
+ for (;;) {
+ error = posix_lock_file(filp, file_lock);
+ if ((error != -EAGAIN) || (cmd == F_SETLK64))
+ break;
+ error = wait_event_interruptible(file_lock->fl_wait,
+ !file_lock->fl_next);
+ if (!error)
+ continue;
- for (;;) {
- error = __posix_lock_file(inode, file_lock);
- if ((error != -EAGAIN) || (cmd == F_SETLK64))
+ locks_delete_block(file_lock);
break;
- error = wait_event_interruptible(file_lock->fl_wait,
- !file_lock->fl_next);
- if (!error)
- continue;
+ }
+ }
- locks_delete_block(file_lock);
- break;
+ /*
+ * Attempt to detect a close/fcntl race and recover by
+ * releasing the lock that was just acquired.
+ */
+ if (!error && fcheck(fd) != filp && flock.l_type != F_UNLCK) {
+ flock.l_type = F_UNLCK;
+ goto again;
}
out:
*/
void locks_remove_posix(struct file *filp, fl_owner_t owner)
{
- struct file_lock lock, **before;
+ struct file_lock lock;
/*
* If there are no locks held on this file, we don't need to call
* 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.
*/
- before = &filp->f_dentry->d_inode->i_flock;
- if (*before == NULL)
+ if (!filp->f_path.dentry->d_inode->i_flock)
return;
lock.fl_type = F_UNLCK;
- lock.fl_flags = FL_POSIX;
+ lock.fl_flags = FL_POSIX | FL_CLOSE;
lock.fl_start = 0;
lock.fl_end = OFFSET_MAX;
lock.fl_owner = owner;
lock.fl_ops = NULL;
lock.fl_lmops = NULL;
- if (filp->f_op && filp->f_op->lock != NULL) {
+ if (filp->f_op && filp->f_op->lock != NULL)
filp->f_op->lock(filp, F_SETLK, &lock);
- goto out;
- }
+ else
+ posix_lock_file(filp, &lock);
- /* Can't use posix_lock_file here; we need to remove it no matter
- * which pid we have.
- */
- lock_kernel();
- while (*before != NULL) {
- struct file_lock *fl = *before;
- if (IS_POSIX(fl) && posix_same_owner(fl, &lock)) {
- locks_delete_lock(before);
- continue;
- }
- before = &fl->fl_next;
- }
- unlock_kernel();
-out:
if (lock.fl_ops && lock.fl_ops->fl_release_private)
lock.fl_ops->fl_release_private(&lock);
}
*/
void locks_remove_flock(struct file *filp)
{
- struct inode * inode = filp->f_dentry->d_inode;
+ struct inode * inode = filp->f_path.dentry->d_inode;
struct file_lock *fl;
struct file_lock **before;
return;
if (filp->f_op && filp->f_op->flock) {
- struct file_lock fl = { .fl_flags = FL_FLOCK,
- .fl_type = F_UNLCK };
+ struct file_lock fl = {
+ .fl_pid = current->tgid,
+ .fl_file = filp,
+ .fl_flags = FL_FLOCK,
+ .fl_type = F_UNLCK,
+ .fl_end = OFFSET_MAX,
+ };
filp->f_op->flock(filp, F_SETLKW, &fl);
+ if (fl.fl_ops && fl.fl_ops->fl_release_private)
+ fl.fl_ops->fl_release_private(&fl);
}
lock_kernel();
while ((fl = *before) != NULL) {
if (fl->fl_file == filp) {
- /*
- * We might have a POSIX lock that was created at the same time
- * the filp was closed for the last time. Just remove that too,
- * regardless of ownership, since nobody can own it.
- */
- if (IS_FLOCK(fl) || IS_POSIX(fl)) {
+ if (IS_FLOCK(fl)) {
locks_delete_lock(before);
continue;
}
unlock_kernel();
}
-/**
- * posix_block_lock - blocks waiting for a file lock
- * @blocker: the lock which is blocking
- * @waiter: the lock which conflicts and has to wait
- *
- * lockd needs to block waiting for locks.
- */
-void
-posix_block_lock(struct file_lock *blocker, struct file_lock *waiter)
-{
- locks_insert_block(blocker, waiter);
-}
-
-EXPORT_SYMBOL(posix_block_lock);
-
/**
* posix_unblock_lock - stop waiting for a file lock
* @filp: how the file was opened
*
* lockd needs to block waiting for locks.
*/
-void
+int
posix_unblock_lock(struct file *filp, struct file_lock *waiter)
{
- /*
- * A remote machine may cancel the lock request after it's been
- * granted locally. If that happens, we need to delete the lock.
- */
+ int status = 0;
+
lock_kernel();
- if (waiter->fl_next) {
+ if (waiter->fl_next)
__locks_delete_block(waiter);
- unlock_kernel();
- } else {
- unlock_kernel();
- waiter->fl_type = F_UNLCK;
- posix_lock_file(filp, waiter);
- }
+ else
+ status = -ENOENT;
+ unlock_kernel();
+ return status;
}
EXPORT_SYMBOL(posix_unblock_lock);
struct inode *inode = NULL;
if (fl->fl_file != NULL)
- inode = fl->fl_file->f_dentry->d_inode;
+ inode = fl->fl_file->f_path.dentry->d_inode;
out += sprintf(out, "%d:%s ", id, pfx);
if (IS_POSIX(fl)) {
list_for_each(tmp, &file_lock_list) {
struct list_head *btmp;
struct file_lock *fl = list_entry(tmp, struct file_lock, fl_link);
+
+ if (!vx_check(fl->fl_xid, VS_WATCH_P|VS_IDENT))
+ continue;
+
lock_get_status(q, fl, ++i, "");
move_lock_status(&q, &pos, offset);
EXPORT_SYMBOL(lock_may_write);
-static inline void __steal_locks(struct file *file, fl_owner_t from)
-{
- struct inode *inode = file->f_dentry->d_inode;
- struct file_lock *fl = inode->i_flock;
-
- while (fl) {
- if (fl->fl_file == file && fl->fl_owner == from)
- fl->fl_owner = current->files;
- fl = fl->fl_next;
- }
-}
-
-/* When getting ready for executing a binary, we make sure that current
- * has a files_struct on its own. Before dropping the old files_struct,
- * we take over ownership of all locks for all file descriptors we own.
- * Note that we may accidentally steal a lock for a file that a sibling
- * has created since the unshare_files() call.
- */
-void steal_locks(fl_owner_t from)
-{
- struct files_struct *files = current->files;
- int i, j;
-
- if (from == files)
- return;
-
- lock_kernel();
- j = 0;
- for (;;) {
- unsigned long set;
- i = j * __NFDBITS;
- if (i >= files->max_fdset || i >= files->max_fds)
- break;
- set = files->open_fds->fds_bits[j++];
- while (set) {
- if (set & 1) {
- struct file *file = files->fd[i];
- if (file)
- __steal_locks(file, from);
- }
- i++;
- set >>= 1;
- }
- }
- unlock_kernel();
-}
-EXPORT_SYMBOL(steal_locks);
-
static int __init filelock_init(void)
{
filelock_cache = kmem_cache_create("file_lock_cache",
git://git.onelab.eu / linux-2.6.git / blobdiff