From 226a998dbf3c6f9b85f67d08a52c5a2143ed9d88 Mon Sep 17 00:00:00 2001
From: "J. Bruce Fields" <bfields@citi.umich.edu>
Date: Wed, 14 Feb 2007 14:25:00 -0500
Subject: locks: trivial removal of unnecessary parentheses

Remove some unnecessary parentheses.

Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
---
 fs/locks.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

(limited to 'fs/locks.c')

diff --git a/fs/locks.c b/fs/locks.c
index 52a81005dab4..1a00b8bc65ed 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -1738,7 +1738,7 @@ again:
 	else {
 		for (;;) {
 			error = posix_lock_file(filp, file_lock);
-			if ((error != -EAGAIN) || (cmd == F_SETLK))
+			if (error != -EAGAIN || cmd == F_SETLK)
 				break;
 			error = wait_event_interruptible(file_lock->fl_wait,
 					!file_lock->fl_next);
@@ -1881,7 +1881,7 @@ again:
 	else {
 		for (;;) {
 			error = posix_lock_file(filp, file_lock);
-			if ((error != -EAGAIN) || (cmd == F_SETLK64))
+			if (error != -EAGAIN || cmd == F_SETLK64)
 				break;
 			error = wait_event_interruptible(file_lock->fl_wait,
 					!file_lock->fl_next);
-- 
cgit v1.2.3


From c2fa1b8a6c059dd08a802545fed3badc8df2adc1 Mon Sep 17 00:00:00 2001
From: "J. Bruce Fields" <bfields@citi.umich.edu>
Date: Tue, 20 Feb 2007 16:10:11 -0500
Subject: locks: create posix-to-flock helper functions

Factor out a bit of messy code by creating posix-to-flock counterparts
to the existing flock-to-posix helper functions.

Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
---
 fs/locks.c | 61 ++++++++++++++++++++++++++++++++++++-------------------------
 1 file changed, 36 insertions(+), 25 deletions(-)

(limited to 'fs/locks.c')

diff --git a/fs/locks.c b/fs/locks.c
index 1a00b8bc65ed..957775ba6468 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -1611,6 +1611,38 @@ asmlinkage long sys_flock(unsigned int fd, unsigned int cmd)
 	return error;
 }
 
+static int posix_lock_to_flock(struct flock *flock, struct file_lock *fl)
+{
+	flock->l_pid = fl->fl_pid;
+#if BITS_PER_LONG == 32
+	/*
+	 * Make sure we can represent the posix lock via
+	 * legacy 32bit flock.
+	 */
+	if (fl->fl_start > OFFT_OFFSET_MAX)
+		return -EOVERFLOW;
+	if (fl->fl_end != OFFSET_MAX && fl->fl_end > OFFT_OFFSET_MAX)
+		return -EOVERFLOW;
+#endif
+	flock->l_start = fl->fl_start;
+	flock->l_len = fl->fl_end == OFFSET_MAX ? 0 :
+		fl->fl_end - fl->fl_start + 1;
+	flock->l_whence = 0;
+	return 0;
+}
+
+#if BITS_PER_LONG == 32
+static void posix_lock_to_flock64(struct flock64 *flock, struct file_lock *fl)
+{
+	flock->l_pid = fl->fl_pid;
+	flock->l_start = fl->fl_start;
+	flock->l_len = fl->fl_end == OFFSET_MAX ? 0 :
+		fl->fl_end - fl->fl_start + 1;
+	flock->l_whence = 0;
+	flock->l_type = fl->fl_type;
+}
+#endif
+
 /* Report the first existing lock that would conflict with l.
  * This implements the F_GETLK command of fcntl().
  */
@@ -1645,24 +1677,9 @@ int fcntl_getlk(struct file *filp, struct flock __user *l)
  
 	flock.l_type = F_UNLCK;
 	if (fl != NULL) {
-		flock.l_pid = fl->fl_pid;
-#if BITS_PER_LONG == 32
-		/*
-		 * Make sure we can represent the posix lock via
-		 * legacy 32bit flock.
-		 */
-		error = -EOVERFLOW;
-		if (fl->fl_start > OFFT_OFFSET_MAX)
-			goto out;
-		if ((fl->fl_end != OFFSET_MAX)
-		    && (fl->fl_end > OFFT_OFFSET_MAX))
+		error = posix_lock_to_flock(&flock, fl);
+		if (error)
 			goto out;
-#endif
-		flock.l_start = fl->fl_start;
-		flock.l_len = fl->fl_end == OFFSET_MAX ? 0 :
-			fl->fl_end - fl->fl_start + 1;
-		flock.l_whence = 0;
-		flock.l_type = fl->fl_type;
 	}
 	error = -EFAULT;
 	if (!copy_to_user(l, &flock, sizeof(flock)))
@@ -1798,14 +1815,8 @@ int fcntl_getlk64(struct file *filp, struct flock64 __user *l)
 	}
  
 	flock.l_type = F_UNLCK;
-	if (fl != NULL) {
-		flock.l_pid = fl->fl_pid;
-		flock.l_start = fl->fl_start;
-		flock.l_len = fl->fl_end == OFFSET_MAX ? 0 :
-			fl->fl_end - fl->fl_start + 1;
-		flock.l_whence = 0;
-		flock.l_type = fl->fl_type;
-	}
+	if (fl != NULL)
+		posix_lock_to_flock64(&flock, fl);
 	error = -EFAULT;
 	if (!copy_to_user(l, &flock, sizeof(flock)))
 		error = 0;
-- 
cgit v1.2.3


From 70cc6487a4e08b8698c0e2ec935fb48d10490162 Mon Sep 17 00:00:00 2001
From: "J. Bruce Fields" <bfields@citi.umich.edu>
Date: Thu, 22 Feb 2007 18:48:53 -0500
Subject: locks: make ->lock release private data before returning in GETLK
 case

The file_lock argument to ->lock is used to return the conflicting lock
when found.  There's no reason for the filesystem to return any private
information with this conflicting lock, but nfsv4 is.

Fix nfsv4 client, and modify locks.c to stop calling fl_release_private
for it in this case.

Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
Cc: "Trond Myklebust" <Trond.Myklebust@netapp.com>"
---
 fs/locks.c        | 4 ----
 fs/nfs/nfs4proc.c | 1 +
 2 files changed, 1 insertion(+), 4 deletions(-)

(limited to 'fs/locks.c')

diff --git a/fs/locks.c b/fs/locks.c
index 957775ba6468..b07e6e6f819b 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -1665,8 +1665,6 @@ int fcntl_getlk(struct file *filp, struct flock __user *l)
 
 	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
@@ -1804,8 +1802,6 @@ int fcntl_getlk64(struct file *filp, struct flock64 __user *l)
 
 	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
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index f52cf5c33c6c..d9000ec52f72 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -3018,6 +3018,7 @@ static int _nfs4_proc_getlk(struct nfs4_state *state, int cmd, struct file_lock
 		case -NFS4ERR_DENIED:
 			status = 0;
 	}
+	request->fl_ops->fl_release_private(request);
 out:
 	up_read(&clp->cl_sem);
 	return status;
-- 
cgit v1.2.3


From 9d6a8c5c213e34c475e72b245a8eb709258e968c Mon Sep 17 00:00:00 2001
From: Marc Eshel <eshel@almaden.ibm.com>
Date: Wed, 21 Feb 2007 00:55:18 -0500
Subject: locks: give posix_test_lock same interface as ->lock

posix_test_lock() and ->lock() do the same job but have gratuitously
different interfaces.  Modify posix_test_lock() so the two agree,
simplifying some code in the process.

Signed-off-by: Marc Eshel <eshel@almaden.ibm.com>
Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
---
 fs/fuse/file.c                |  3 +--
 fs/gfs2/locking/nolock/main.c |  8 +-------
 fs/gfs2/ops_file.c            |  7 +------
 fs/lockd/svclock.c            | 13 ++++++++-----
 fs/locks.c                    | 37 ++++++++++++++++---------------------
 fs/nfs/file.c                 |  7 +------
 fs/nfsd/nfs4state.c           |  6 +++---
 include/linux/fs.h            |  2 +-
 8 files changed, 32 insertions(+), 51 deletions(-)

(limited to 'fs/locks.c')

diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index 2fd06927e851..acfad65a6e8e 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -738,8 +738,7 @@ static int fuse_file_lock(struct file *file, int cmd, struct file_lock *fl)
 
 	if (cmd == F_GETLK) {
 		if (fc->no_lock) {
-			if (!posix_test_lock(file, fl, fl))
-				fl->fl_type = F_UNLCK;
+			posix_test_lock(file, fl);
 			err = 0;
 		} else
 			err = fuse_getlk(file, fl);
diff --git a/fs/gfs2/locking/nolock/main.c b/fs/gfs2/locking/nolock/main.c
index acfbc941f319..5cc1dfa7944a 100644
--- a/fs/gfs2/locking/nolock/main.c
+++ b/fs/gfs2/locking/nolock/main.c
@@ -164,13 +164,7 @@ static void nolock_unhold_lvb(void *lock, char *lvb)
 static int nolock_plock_get(void *lockspace, struct lm_lockname *name,
 			    struct file *file, struct file_lock *fl)
 {
-	struct file_lock tmp;
-	int ret;
-
-	ret = posix_test_lock(file, fl, &tmp);
-	fl->fl_type = F_UNLCK;
-	if (ret)
-		memcpy(fl, &tmp, sizeof(struct file_lock));
+	posix_test_lock(file, fl);
 
 	return 0;
 }
diff --git a/fs/gfs2/ops_file.c b/fs/gfs2/ops_file.c
index b50180e22779..48b248d7c823 100644
--- a/fs/gfs2/ops_file.c
+++ b/fs/gfs2/ops_file.c
@@ -513,12 +513,7 @@ static int gfs2_lock(struct file *file, int cmd, struct file_lock *fl)
 
 	if (sdp->sd_args.ar_localflocks) {
 		if (IS_GETLK(cmd)) {
-			struct file_lock tmp;
-			int ret;
-			ret = posix_test_lock(file, fl, &tmp);
-			fl->fl_type = F_UNLCK;
-			if (ret)
-				memcpy(fl, &tmp, sizeof(struct file_lock));
+			posix_test_lock(file, fl);
 			return 0;
 		} else {
 			return posix_lock_file_wait(file, fl);
diff --git a/fs/lockd/svclock.c b/fs/lockd/svclock.c
index cf51f849e76c..97b0160ef10f 100644
--- a/fs/lockd/svclock.c
+++ b/fs/lockd/svclock.c
@@ -426,15 +426,18 @@ nlmsvc_testlock(struct nlm_file *file, struct nlm_lock *lock,
 				(long long)lock->fl.fl_start,
 				(long long)lock->fl.fl_end);
 
-	if (posix_test_lock(file->f_file, &lock->fl, &conflock->fl)) {
+	if (posix_test_lock(file->f_file, &lock->fl)) {
 		dprintk("lockd: conflicting lock(ty=%d, %Ld-%Ld)\n",
-				conflock->fl.fl_type,
-				(long long)conflock->fl.fl_start,
-				(long long)conflock->fl.fl_end);
+				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 = conflock->fl.fl_pid;
+		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;
 		return nlm_lck_denied;
 	}
 
diff --git a/fs/locks.c b/fs/locks.c
index b07e6e6f819b..749a0dc7cd4b 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -666,11 +666,11 @@ static int locks_block_on_timeout(struct file_lock *blocker, struct file_lock *w
 }
 
 int
-posix_test_lock(struct file *filp, struct file_lock *fl,
-		struct file_lock *conflock)
+posix_test_lock(struct file *filp, struct file_lock *fl)
 {
 	struct file_lock *cfl;
 
+	fl->fl_type = F_UNLCK;
 	lock_kernel();
 	for (cfl = filp->f_path.dentry->d_inode->i_flock; cfl; cfl = cfl->fl_next) {
 		if (!IS_POSIX(cfl))
@@ -679,7 +679,7 @@ posix_test_lock(struct file *filp, struct file_lock *fl,
 			break;
 	}
 	if (cfl) {
-		__locks_copy_lock(conflock, cfl);
+		__locks_copy_lock(fl, cfl);
 		unlock_kernel();
 		return 1;
 	}
@@ -1648,7 +1648,7 @@ static void posix_lock_to_flock64(struct flock64 *flock, struct file_lock *fl)
  */
 int fcntl_getlk(struct file *filp, struct flock __user *l)
 {
-	struct file_lock *fl, cfl, file_lock;
+	struct file_lock file_lock;
 	struct flock flock;
 	int error;
 
@@ -1667,15 +1667,12 @@ int fcntl_getlk(struct file *filp, struct flock __user *l)
 		error = filp->f_op->lock(filp, F_GETLK, &file_lock);
 		if (error < 0)
 			goto out;
-		else
-		  fl = (file_lock.fl_type == F_UNLCK ? NULL : &file_lock);
-	} else {
-		fl = (posix_test_lock(filp, &file_lock, &cfl) ? &cfl : NULL);
-	}
+	} else
+		posix_test_lock(filp, &file_lock);
  
-	flock.l_type = F_UNLCK;
-	if (fl != NULL) {
-		error = posix_lock_to_flock(&flock, fl);
+	flock.l_type = file_lock.fl_type;
+	if (file_lock.fl_type != F_UNLCK) {
+		error = posix_lock_to_flock(&flock, &file_lock);
 		if (error)
 			goto out;
 	}
@@ -1785,7 +1782,7 @@ out:
  */
 int fcntl_getlk64(struct file *filp, struct flock64 __user *l)
 {
-	struct file_lock *fl, cfl, file_lock;
+	struct file_lock file_lock;
 	struct flock64 flock;
 	int error;
 
@@ -1804,15 +1801,13 @@ int fcntl_getlk64(struct file *filp, struct flock64 __user *l)
 		error = filp->f_op->lock(filp, F_GETLK, &file_lock);
 		if (error < 0)
 			goto out;
-		else
-		  fl = (file_lock.fl_type == F_UNLCK ? NULL : &file_lock);
-	} else {
-		fl = (posix_test_lock(filp, &file_lock, &cfl) ? &cfl : NULL);
-	}
+	} else
+		posix_test_lock(filp, &file_lock);
  
-	flock.l_type = F_UNLCK;
-	if (fl != NULL)
-		posix_lock_to_flock64(&flock, fl);
+	flock.l_type = file_lock.fl_type;
+	if (file_lock.fl_type != F_UNLCK)
+		posix_lock_to_flock64(&flock, &file_lock);
+
 	error = -EFAULT;
 	if (!copy_to_user(l, &flock, sizeof(flock)))
 		error = 0;
diff --git a/fs/nfs/file.c b/fs/nfs/file.c
index 8e66b5a2d490..5eaee6dd040b 100644
--- a/fs/nfs/file.c
+++ b/fs/nfs/file.c
@@ -391,17 +391,12 @@ out_swapfile:
 
 static int do_getlk(struct file *filp, int cmd, struct file_lock *fl)
 {
-	struct file_lock cfl;
 	struct inode *inode = filp->f_mapping->host;
 	int status = 0;
 
 	lock_kernel();
 	/* Try local locking first */
-	if (posix_test_lock(filp, fl, &cfl)) {
-		fl->fl_start = cfl.fl_start;
-		fl->fl_end = cfl.fl_end;
-		fl->fl_type = cfl.fl_type;
-		fl->fl_pid = cfl.fl_pid;
+	if (posix_test_lock(filp, fl)) {
 		goto out;
 	}
 
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index af360705e551..e42c7a0eb6fa 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -2813,7 +2813,6 @@ nfsd4_lockt(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
 	struct inode *inode;
 	struct file file;
 	struct file_lock file_lock;
-	struct file_lock conflock;
 	__be32 status;
 
 	if (nfs4_in_grace())
@@ -2878,9 +2877,10 @@ nfsd4_lockt(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
 	file.f_path.dentry = cstate->current_fh.fh_dentry;
 
 	status = nfs_ok;
-	if (posix_test_lock(&file, &file_lock, &conflock)) {
+	posix_test_lock(&file, &file_lock);
+	if (file_lock.fl_type != F_UNLCK) {
 		status = nfserr_denied;
-		nfs4_set_lock_denied(&conflock, &lockt->lt_denied);
+		nfs4_set_lock_denied(&file_lock, &lockt->lt_denied);
 	}
 out:
 	nfs4_unlock_state();
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 86ec3f4a7da6..9e1ddffe3884 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -851,7 +851,7 @@ extern void locks_init_lock(struct file_lock *);
 extern void locks_copy_lock(struct file_lock *, struct file_lock *);
 extern void locks_remove_posix(struct file *, fl_owner_t);
 extern void locks_remove_flock(struct file *);
-extern int posix_test_lock(struct file *, struct file_lock *, struct file_lock *);
+extern int posix_test_lock(struct file *, struct file_lock *);
 extern int posix_lock_file_conf(struct file *, struct file_lock *, struct file_lock *);
 extern int posix_lock_file(struct file *, struct file_lock *);
 extern int posix_lock_file_wait(struct file *, struct file_lock *);
-- 
cgit v1.2.3


From 3ee17abd14c728d4e0ca7a991c58f2250cb091af Mon Sep 17 00:00:00 2001
From: "J. Bruce Fields" <bfields@citi.umich.edu>
Date: Wed, 21 Feb 2007 00:58:50 -0500
Subject: locks: factor out generic/filesystem switch from test_lock

Factor out the code that switches between generic and filesystem-specific lock
methods; eventually we want to call this from lock managers (lockd and nfsd)
too; currently they only call the generic methods.

This patch does that for test_lock.

Note that this hasn't been necessary until recently, because the few
filesystems that define ->lock() (nfs, cifs...) aren't exportable via NFS.
However GFS (and, in the future, other cluster filesystems) need to implement
their own locking to get cluster-coherent locking, and also want to be able to
export locking to NFS (lockd and NFSv4).

So we accomplish this by factoring out code such as this and exporting it for
the use of lockd and nfsd.

Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
---
 fs/locks.c         | 38 +++++++++++++++++++++++++-------------
 include/linux/fs.h |  1 +
 2 files changed, 26 insertions(+), 13 deletions(-)

(limited to 'fs/locks.c')

diff --git a/fs/locks.c b/fs/locks.c
index 749a0dc7cd4b..a31648e3ec1b 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -1611,6 +1611,24 @@ asmlinkage long sys_flock(unsigned int fd, unsigned int cmd)
 	return error;
 }
 
+/**
+ * vfs_test_lock - test file byte range lock
+ * @filp: The file to test lock for
+ * @fl: The lock to test
+ * @conf: Place to return a copy of the conflicting lock, if found
+ *
+ * Returns -ERRNO on failure.  Indicates presence of conflicting lock by
+ * setting conf->fl_type to something other than F_UNLCK.
+ */
+int vfs_test_lock(struct file *filp, struct file_lock *fl)
+{
+	if (filp->f_op && filp->f_op->lock)
+		return filp->f_op->lock(filp, F_GETLK, fl);
+	posix_test_lock(filp, fl);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(vfs_test_lock);
+
 static int posix_lock_to_flock(struct flock *flock, struct file_lock *fl)
 {
 	flock->l_pid = fl->fl_pid;
@@ -1663,12 +1681,9 @@ int fcntl_getlk(struct file *filp, struct flock __user *l)
 	if (error)
 		goto out;
 
-	if (filp->f_op && filp->f_op->lock) {
-		error = filp->f_op->lock(filp, F_GETLK, &file_lock);
-		if (error < 0)
-			goto out;
-	} else
-		posix_test_lock(filp, &file_lock);
+	error = vfs_test_lock(filp, &file_lock);
+	if (error)
+		goto out;
  
 	flock.l_type = file_lock.fl_type;
 	if (file_lock.fl_type != F_UNLCK) {
@@ -1797,13 +1812,10 @@ int fcntl_getlk64(struct file *filp, struct flock64 __user *l)
 	if (error)
 		goto out;
 
-	if (filp->f_op && filp->f_op->lock) {
-		error = filp->f_op->lock(filp, F_GETLK, &file_lock);
-		if (error < 0)
-			goto out;
-	} else
-		posix_test_lock(filp, &file_lock);
- 
+	error = vfs_test_lock(filp, &file_lock);
+	if (error)
+		goto out;
+
 	flock.l_type = file_lock.fl_type;
 	if (file_lock.fl_type != F_UNLCK)
 		posix_lock_to_flock64(&flock, &file_lock);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 9e1ddffe3884..2a2a43988f50 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -856,6 +856,7 @@ extern int posix_lock_file_conf(struct file *, struct file_lock *, struct file_l
 extern int posix_lock_file(struct file *, struct file_lock *);
 extern int posix_lock_file_wait(struct file *, struct file_lock *);
 extern int posix_unblock_lock(struct file *, struct file_lock *);
+extern int vfs_test_lock(struct file *, struct file_lock *);
 extern int flock_lock_file_wait(struct file *filp, struct file_lock *fl);
 extern int __break_lease(struct inode *inode, unsigned int flags);
 extern void lease_get_mtime(struct inode *, struct timespec *time);
-- 
cgit v1.2.3


From 7723ec9777d9832849b76475b1a21a2872a40d20 Mon Sep 17 00:00:00 2001
From: Marc Eshel <eshel@almaden.ibm.com>
Date: Thu, 18 Jan 2007 15:08:55 -0500
Subject: locks: factor out generic/filesystem switch from setlock code

Factor out the code that switches between generic and filesystem-specific lock
methods; eventually we want to call this from lock managers (lockd and nfsd)
too; currently they only call the generic methods.

This patch does that for all the setlk code.

Signed-off-by: Marc Eshel <eshel@almaden.ibm.com>
Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
---
 fs/locks.c         | 68 +++++++++++++++++++++++++++++-------------------------
 include/linux/fs.h |  1 +
 2 files changed, 37 insertions(+), 32 deletions(-)

(limited to 'fs/locks.c')

diff --git a/fs/locks.c b/fs/locks.c
index a31648e3ec1b..f4fd1515b6e2 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -1698,6 +1698,21 @@ out:
 	return error;
 }
 
+/**
+ * vfs_lock_file - file byte range lock
+ * @filp: The file to apply the lock to
+ * @cmd: type of locking operation (F_SETLK, F_GETLK, etc.)
+ * @fl: The lock to be applied
+ */
+int vfs_lock_file(struct file *filp, unsigned int cmd, struct file_lock *fl)
+{
+	if (filp->f_op && filp->f_op->lock)
+		return filp->f_op->lock(filp, cmd, fl);
+	else
+		return posix_lock_file(filp, fl);
+}
+EXPORT_SYMBOL_GPL(vfs_lock_file);
+
 /* Apply the lock described by l to an open file descriptor.
  * This implements both the F_SETLK and F_SETLKW commands of fcntl().
  */
@@ -1760,21 +1775,17 @@ again:
 	if (error)
 		goto out;
 
-	if (filp->f_op && filp->f_op->lock != NULL)
-		error = filp->f_op->lock(filp, cmd, file_lock);
-	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;
-
-			locks_delete_block(file_lock);
+	for (;;) {
+		error = vfs_lock_file(filp, cmd, file_lock);
+		if (error != -EAGAIN || cmd == F_SETLK)
 			break;
-		}
+		error = wait_event_interruptible(file_lock->fl_wait,
+				!file_lock->fl_next);
+		if (!error)
+			continue;
+
+		locks_delete_block(file_lock);
+		break;
 	}
 
 	/*
@@ -1890,21 +1901,17 @@ again:
 	if (error)
 		goto out;
 
-	if (filp->f_op && filp->f_op->lock != NULL)
-		error = filp->f_op->lock(filp, cmd, file_lock);
-	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;
-
-			locks_delete_block(file_lock);
+	for (;;) {
+		error = vfs_lock_file(filp, cmd, file_lock);
+		if (error != -EAGAIN || cmd == F_SETLK64)
 			break;
-		}
+		error = wait_event_interruptible(file_lock->fl_wait,
+				!file_lock->fl_next);
+		if (!error)
+			continue;
+
+		locks_delete_block(file_lock);
+		break;
 	}
 
 	/*
@@ -1949,10 +1956,7 @@ void locks_remove_posix(struct file *filp, fl_owner_t owner)
 	lock.fl_ops = NULL;
 	lock.fl_lmops = NULL;
 
-	if (filp->f_op && filp->f_op->lock != NULL)
-		filp->f_op->lock(filp, F_SETLK, &lock);
-	else
-		posix_lock_file(filp, &lock);
+	vfs_lock_file(filp, F_SETLK, &lock);
 
 	if (lock.fl_ops && lock.fl_ops->fl_release_private)
 		lock.fl_ops->fl_release_private(&lock);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 2a2a43988f50..1d5ccdd7c68d 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -857,6 +857,7 @@ extern int posix_lock_file(struct file *, struct file_lock *);
 extern int posix_lock_file_wait(struct file *, struct file_lock *);
 extern int posix_unblock_lock(struct file *, struct file_lock *);
 extern int vfs_test_lock(struct file *, struct file_lock *);
+extern int vfs_lock_file(struct file *, unsigned int, struct file_lock *);
 extern int flock_lock_file_wait(struct file *filp, struct file_lock *fl);
 extern int __break_lease(struct inode *inode, unsigned int flags);
 extern void lease_get_mtime(struct inode *, struct timespec *time);
-- 
cgit v1.2.3


From 150b393456e5a23513cace286a019e87151e47f0 Mon Sep 17 00:00:00 2001
From: Marc Eshel <eshel@almaden.ibm.com>
Date: Thu, 18 Jan 2007 16:15:35 -0500
Subject: locks: allow {vfs,posix}_lock_file to return conflicting lock

The nfsv4 protocol's lock operation, in the case of a conflict, returns
information about the conflicting lock.

It's unclear how clients can use this, so for now we're not going so far as to
add a filesystem method that can return a conflicting lock, but we may as well
return something in the local case when it's easy to.

Signed-off-by: Marc Eshel <eshel@almaden.ibm.com>
Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
---
 fs/lockd/svclock.c  |  6 +++---
 fs/lockd/svcsubs.c  |  2 +-
 fs/locks.c          | 45 ++++++++++++++++++++-------------------------
 fs/nfsd/nfs4state.c | 10 ++++++----
 include/linux/fs.h  |  5 ++---
 5 files changed, 32 insertions(+), 36 deletions(-)

(limited to 'fs/locks.c')

diff --git a/fs/lockd/svclock.c b/fs/lockd/svclock.c
index 97b0160ef10f..3b0e7a4b817b 100644
--- a/fs/lockd/svclock.c
+++ b/fs/lockd/svclock.c
@@ -363,7 +363,7 @@ again:
 	} else
 		lock = &block->b_call->a_args.lock;
 
-	error = posix_lock_file(file->f_file, &lock->fl);
+	error = posix_lock_file(file->f_file, &lock->fl, NULL);
 	lock->fl.fl_flags &= ~FL_SLEEP;
 
 	dprintk("lockd: posix_lock_file returned %d\n", error);
@@ -467,7 +467,7 @@ nlmsvc_unlock(struct nlm_file *file, struct nlm_lock *lock)
 	nlmsvc_cancel_blocked(file, lock);
 
 	lock->fl.fl_type = F_UNLCK;
-	error = posix_lock_file(file->f_file, &lock->fl);
+	error = posix_lock_file(file->f_file, &lock->fl, NULL);
 
 	return (error < 0)? nlm_lck_denied_nolocks : nlm_granted;
 }
@@ -569,7 +569,7 @@ nlmsvc_grant_blocked(struct nlm_block *block)
 
 	/* Try the lock operation again */
 	lock->fl.fl_flags |= FL_SLEEP;
-	error = posix_lock_file(file->f_file, &lock->fl);
+	error = posix_lock_file(file->f_file, &lock->fl, NULL);
 	lock->fl.fl_flags &= ~FL_SLEEP;
 
 	switch (error) {
diff --git a/fs/lockd/svcsubs.c b/fs/lockd/svcsubs.c
index c0df00c74ce3..50957089be1f 100644
--- a/fs/lockd/svcsubs.c
+++ b/fs/lockd/svcsubs.c
@@ -182,7 +182,7 @@ again:
 			lock.fl_type  = F_UNLCK;
 			lock.fl_start = 0;
 			lock.fl_end   = OFFSET_MAX;
-			if (posix_lock_file(file->f_file, &lock) < 0) {
+			if (posix_lock_file(file->f_file, &lock, NULL) < 0) {
 				printk("lockd: unlock failure in %s:%d\n",
 						__FILE__, __LINE__);
 				return 1;
diff --git a/fs/locks.c b/fs/locks.c
index f4fd1515b6e2..ee46584c1a40 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -801,7 +801,7 @@ out:
 	return error;
 }
 
-static int __posix_lock_file_conf(struct inode *inode, struct file_lock *request, struct file_lock *conflock)
+static int __posix_lock_file(struct inode *inode, struct file_lock *request, struct file_lock *conflock)
 {
 	struct file_lock *fl;
 	struct file_lock *new_fl = NULL;
@@ -1007,6 +1007,7 @@ static int __posix_lock_file_conf(struct inode *inode, struct file_lock *request
  * posix_lock_file - 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.
  *
  * Add a POSIX style lock to a file.
  * We merge adjacent & overlapping locks whenever possible.
@@ -1016,26 +1017,12 @@ static int __posix_lock_file_conf(struct inode *inode, struct file_lock *request
  * 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_conf(filp->f_path.dentry->d_inode, fl, NULL);
-}
-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,
+int posix_lock_file(struct file *filp, struct file_lock *fl,
 			struct file_lock *conflock)
 {
-	return __posix_lock_file_conf(filp->f_path.dentry->d_inode, fl, conflock);
+	return __posix_lock_file(filp->f_path.dentry->d_inode, fl, conflock);
 }
-EXPORT_SYMBOL(posix_lock_file_conf);
+EXPORT_SYMBOL(posix_lock_file);
 
 /**
  * posix_lock_file_wait - Apply a POSIX-style lock to a file
@@ -1051,7 +1038,7 @@ int posix_lock_file_wait(struct file *filp, struct file_lock *fl)
 	int error;
 	might_sleep ();
 	for (;;) {
-		error = posix_lock_file(filp, fl);
+		error = posix_lock_file(filp, fl, NULL);
 		if ((error != -EAGAIN) || !(fl->fl_flags & FL_SLEEP))
 			break;
 		error = wait_event_interruptible(fl->fl_wait, !fl->fl_next);
@@ -1123,7 +1110,7 @@ int locks_mandatory_area(int read_write, struct inode *inode,
 	fl.fl_end = offset + count - 1;
 
 	for (;;) {
-		error = __posix_lock_file_conf(inode, &fl, NULL);
+		error = __posix_lock_file(inode, &fl, NULL);
 		if (error != -EAGAIN)
 			break;
 		if (!(fl.fl_flags & FL_SLEEP))
@@ -1703,13 +1690,21 @@ out:
  * @filp: The file to apply the lock to
  * @cmd: type of locking operation (F_SETLK, F_GETLK, etc.)
  * @fl: The lock to be applied
+ * @conf: Place to return a copy of the conflicting lock, if found.
+ *
+ * A caller that doesn't care about the conflicting lock may pass NULL
+ * as the final argument.
+ *
+ * If the filesystem defines a private ->lock() method, then @conf will
+ * be left unchanged; so a caller that cares should initialize it to
+ * some acceptable default.
  */
-int vfs_lock_file(struct file *filp, unsigned int cmd, struct file_lock *fl)
+int vfs_lock_file(struct file *filp, unsigned int cmd, struct file_lock *fl, struct file_lock *conf)
 {
 	if (filp->f_op && filp->f_op->lock)
 		return filp->f_op->lock(filp, cmd, fl);
 	else
-		return posix_lock_file(filp, fl);
+		return posix_lock_file(filp, fl, conf);
 }
 EXPORT_SYMBOL_GPL(vfs_lock_file);
 
@@ -1776,7 +1771,7 @@ again:
 		goto out;
 
 	for (;;) {
-		error = vfs_lock_file(filp, cmd, file_lock);
+		error = vfs_lock_file(filp, cmd, file_lock, NULL);
 		if (error != -EAGAIN || cmd == F_SETLK)
 			break;
 		error = wait_event_interruptible(file_lock->fl_wait,
@@ -1902,7 +1897,7 @@ again:
 		goto out;
 
 	for (;;) {
-		error = vfs_lock_file(filp, cmd, file_lock);
+		error = vfs_lock_file(filp, cmd, file_lock, NULL);
 		if (error != -EAGAIN || cmd == F_SETLK64)
 			break;
 		error = wait_event_interruptible(file_lock->fl_wait,
@@ -1956,7 +1951,7 @@ void locks_remove_posix(struct file *filp, fl_owner_t owner)
 	lock.fl_ops = NULL;
 	lock.fl_lmops = NULL;
 
-	vfs_lock_file(filp, F_SETLK, &lock);
+	vfs_lock_file(filp, F_SETLK, &lock, NULL);
 
 	if (lock.fl_ops && lock.fl_ops->fl_release_private)
 		lock.fl_ops->fl_release_private(&lock);
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index e42c7a0eb6fa..03b0578781cb 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -2657,6 +2657,7 @@ nfsd4_lock(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
 	struct file_lock conflock;
 	__be32 status = 0;
 	unsigned int strhashval;
+	unsigned int cmd;
 	int err;
 
 	dprintk("NFSD: nfsd4_lock: start=%Ld length=%Ld\n",
@@ -2739,10 +2740,12 @@ nfsd4_lock(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
 		case NFS4_READ_LT:
 		case NFS4_READW_LT:
 			file_lock.fl_type = F_RDLCK;
+			cmd = F_SETLK;
 		break;
 		case NFS4_WRITE_LT:
 		case NFS4_WRITEW_LT:
 			file_lock.fl_type = F_WRLCK;
+			cmd = F_SETLK;
 		break;
 		default:
 			status = nfserr_inval;
@@ -2769,9 +2772,8 @@ nfsd4_lock(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
 
 	/* XXX?: Just to divert the locks_release_private at the start of
 	 * locks_copy_lock: */
-	conflock.fl_ops = NULL;
-	conflock.fl_lmops = NULL;
-	err = posix_lock_file_conf(filp, &file_lock, &conflock);
+	locks_init_lock(&conflock);
+	err = posix_lock_file(filp, &file_lock, &conflock);
 	switch (-err) {
 	case 0: /* success! */
 		update_stateid(&lock_stp->st_stateid);
@@ -2933,7 +2935,7 @@ nfsd4_locku(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
 	/*
 	*  Try to unlock the file in the VFS.
 	*/
-	err = posix_lock_file(filp, &file_lock);
+	err = posix_lock_file(filp, &file_lock, NULL);
 	if (err) {
 		dprintk("NFSD: nfs4_locku: posix_lock_file failed!\n");
 		goto out_nfserr;
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 1d5ccdd7c68d..c92d0bdff39f 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -852,12 +852,11 @@ extern void locks_copy_lock(struct file_lock *, struct file_lock *);
 extern void locks_remove_posix(struct file *, fl_owner_t);
 extern void locks_remove_flock(struct file *);
 extern int posix_test_lock(struct file *, struct file_lock *);
-extern int posix_lock_file_conf(struct file *, struct file_lock *, struct file_lock *);
-extern int posix_lock_file(struct file *, struct file_lock *);
+extern int posix_lock_file(struct file *, struct file_lock *, struct file_lock *);
 extern int posix_lock_file_wait(struct file *, struct file_lock *);
 extern int posix_unblock_lock(struct file *, struct file_lock *);
 extern int vfs_test_lock(struct file *, struct file_lock *);
-extern int vfs_lock_file(struct file *, unsigned int, struct file_lock *);
+extern int vfs_lock_file(struct file *, unsigned int, struct file_lock *, struct file_lock *);
 extern int flock_lock_file_wait(struct file *filp, struct file_lock *fl);
 extern int __break_lease(struct inode *inode, unsigned int flags);
 extern void lease_get_mtime(struct inode *, struct timespec *time);
-- 
cgit v1.2.3


From 9b9d2ab4154a42ea4a119f7d3e4e0288bfe0bb79 Mon Sep 17 00:00:00 2001
From: Marc Eshel <eshel@almaden.ibm.com>
Date: Thu, 18 Jan 2007 17:52:58 -0500
Subject: locks: add lock cancel command

Lock managers need to be able to cancel pending lock requests.  In the case
where the exported filesystem manages its own locks, it's not sufficient just
to call posix_unblock_lock(); we need to let the filesystem know what's
happening too.

We do this by adding a new fcntl lock command: FL_CANCELLK.  Some day this
might also be made available to userspace applications that could benefit from
an asynchronous locking api.

Signed-off-by: Marc Eshel <eshel@almaden.ibm.com>
Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
---
 fs/locks.c            | 16 ++++++++++++++++
 include/linux/fcntl.h |  4 ++++
 include/linux/fs.h    |  1 +
 3 files changed, 21 insertions(+)

(limited to 'fs/locks.c')

diff --git a/fs/locks.c b/fs/locks.c
index ee46584c1a40..242328e17f32 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -2028,6 +2028,22 @@ posix_unblock_lock(struct file *filp, struct file_lock *waiter)
 
 EXPORT_SYMBOL(posix_unblock_lock);
 
+/**
+ * vfs_cancel_lock - file byte range unblock lock
+ * @filp: The file to apply the unblock to
+ * @fl: The lock to be unblocked
+ *
+ * Used by lock managers to cancel blocked requests
+ */
+int vfs_cancel_lock(struct file *filp, struct file_lock *fl)
+{
+	if (filp->f_op && filp->f_op->lock)
+		return filp->f_op->lock(filp, F_CANCELLK, fl);
+	return 0;
+}
+
+EXPORT_SYMBOL_GPL(vfs_cancel_lock);
+
 static void lock_get_status(char* out, struct file_lock *fl, int id, char *pfx)
 {
 	struct inode *inode = NULL;
diff --git a/include/linux/fcntl.h b/include/linux/fcntl.h
index 996f5611cd59..40b93265d4ba 100644
--- a/include/linux/fcntl.h
+++ b/include/linux/fcntl.h
@@ -3,6 +3,10 @@
 
 #include <asm/fcntl.h>
 
+/* Cancel a blocking posix lock; internal use only until we expose an
+ * asynchronous lock api to userspace: */
+#define F_CANCELLK	(F_LINUX_SPECIFIC_BASE+5)
+
 #define F_SETLEASE	(F_LINUX_SPECIFIC_BASE+0)
 #define F_GETLEASE	(F_LINUX_SPECIFIC_BASE+1)
 
diff --git a/include/linux/fs.h b/include/linux/fs.h
index c92d0bdff39f..64b8ae205309 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -857,6 +857,7 @@ extern int posix_lock_file_wait(struct file *, struct file_lock *);
 extern int posix_unblock_lock(struct file *, struct file_lock *);
 extern int vfs_test_lock(struct file *, struct file_lock *);
 extern int vfs_lock_file(struct file *, unsigned int, struct file_lock *, struct file_lock *);
+extern int vfs_cancel_lock(struct file *filp, struct file_lock *fl);
 extern int flock_lock_file_wait(struct file *filp, struct file_lock *fl);
 extern int __break_lease(struct inode *inode, unsigned int flags);
 extern void lease_get_mtime(struct inode *, struct timespec *time);
-- 
cgit v1.2.3


From 2beb6614f5e36c6165b704c167d82ef3e4ceaa0c Mon Sep 17 00:00:00 2001
From: Marc Eshel <eshel@almaden.ibm.com>
Date: Tue, 5 Dec 2006 23:31:28 -0500
Subject: locks: add fl_grant callback for asynchronous lock return

Acquiring a lock on a cluster filesystem may require communication with
remote hosts, and to avoid blocking lockd or nfsd threads during such
communication, we allow the results to be returned asynchronously.

When a ->lock() call needs to block, the file system will return
-EINPROGRESS, and then later return the results with a call to the
routine in the fl_grant field of the lock_manager_operations struct.

This differs from the case when ->lock returns -EAGAIN to a blocking
lock request; in that case, the filesystem calls fl_notify when the lock
is granted, and the caller retries the original lock.  So while
fl_notify is merely a hint to the caller that it should retry, fl_grant
actually communicates the final result of the lock operation (with the
lock already acquired in the succesful case).

Therefore fl_grant takes a lock, a status and, for the test lock case, a
conflicting lock.  We also allow fl_grant to return an error to the
filesystem, to handle the case where the fl_grant requests arrives after
the lock manager has already given up waiting for it.

Signed-off-by: Marc Eshel <eshel@almaden.ibm.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
---
 fs/locks.c         | 19 +++++++++++++++++++
 include/linux/fs.h |  1 +
 2 files changed, 20 insertions(+)

(limited to 'fs/locks.c')

diff --git a/fs/locks.c b/fs/locks.c
index 242328e17f32..53b0cd153202 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -1698,6 +1698,25 @@ out:
  * If the filesystem defines a private ->lock() method, then @conf will
  * be left unchanged; so a caller that cares should initialize it to
  * some acceptable default.
+ *
+ * To avoid blocking kernel daemons, such as lockd, that need to acquire POSIX
+ * locks, the ->lock() interface may return asynchronously, before the lock has
+ * been granted or denied by the underlying filesystem, if (and only if)
+ * fl_grant is set. Callers expecting ->lock() to return asynchronously
+ * will only use F_SETLK, not F_SETLKW; they will set FL_SLEEP if (and only if)
+ * the request is for a blocking lock. When ->lock() does return asynchronously,
+ * it must return -EINPROGRESS, and call ->fl_grant() when the lock
+ * request completes.
+ * If the request is for non-blocking lock the file system should return
+ * -EINPROGRESS then try to get the lock and call the callback routine with
+ * the result. If the request timed out the callback routine will return a
+ * nonzero return code and the file system should release the lock. The file
+ * system is also responsible to keep a corresponding posix lock when it
+ * grants a lock so the VFS can find out which locks are locally held and do
+ * the correct lock cleanup when required.
+ * The underlying filesystem must not drop the kernel lock or call
+ * ->fl_grant() before returning to the caller with a -EINPROGRESS
+ * return code.
  */
 int vfs_lock_file(struct file *filp, unsigned int cmd, struct file_lock *fl, struct file_lock *conf)
 {
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 64b8ae205309..b22991d5f16b 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -785,6 +785,7 @@ struct file_lock_operations {
 struct lock_manager_operations {
 	int (*fl_compare_owner)(struct file_lock *, struct file_lock *);
 	void (*fl_notify)(struct file_lock *);	/* unblock callback */
+	int (*fl_grant)(struct file_lock *, struct file_lock *, int);
 	void (*fl_copy_lock)(struct file_lock *, struct file_lock *);
 	void (*fl_release_private)(struct file_lock *);
 	void (*fl_break)(struct file_lock *);
-- 
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