fs/ufs: restore s_lock mutex

commit cdd9eefdf905e92e7fc6cc393314efe68dc6ff66 upstream.

Commit 0244756edc4b98c ("ufs: sb mutex merge + mutex_destroy") generated
deadlocks in read/write mode on mkdir.

This patch partially reverts it keeping fixes by Andrew Morton and
mutex_destroy()

[AV: fixed a missing bit in ufs_remount()]

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Reported-by: Ian Campbell <ian.campbell@citrix.com>
Suggested-by: Jan Kara <jack@suse.cz>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Evgeniy Dushistov <dushistov@mail.ru>
Cc: Alexey Khoroshilov <khoroshilov@ispras.ru>
Cc: Roger Pau Monne <roger.pau@citrix.com>
Cc: Ian Jackson <Ian.Jackson@eu.citrix.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

4 files changed, 36 insertions, 25 deletions

diff --git a/fs/ufs/balloc.c b/fs/ufs/balloc.c
index 2c1036080d52..a7106eda5024 100644
--- a/fs/ufs/balloc.c
+++ b/fs/ufs/balloc.c
@@ -51,8 +51,8 @@ void ufs_free_fragments(struct inode *inode, u64 fragment, unsigned count)
         
         if (ufs_fragnum(fragment) + count > uspi->s_fpg)
                 ufs_error (sb, "ufs_free_fragments", "internal error");
-        
-        lock_ufs(sb);
+
+        mutex_lock(&UFS_SB(sb)->s_lock);
         
         cgno = ufs_dtog(uspi, fragment);
         bit = ufs_dtogd(uspi, fragment);
@@ -115,13 +115,13 @@ void ufs_free_fragments(struct inode *inode, u64 fragment, unsigned count)
         if (sb->s_flags & MS_SYNCHRONOUS)
                 ubh_sync_block(UCPI_UBH(ucpi));
         ufs_mark_sb_dirty(sb);
-        
-        unlock_ufs(sb);
+
+        mutex_unlock(&UFS_SB(sb)->s_lock);
         UFSD("EXIT\n");
         return;
 
 failed:
-        unlock_ufs(sb);
+        mutex_unlock(&UFS_SB(sb)->s_lock);
         UFSD("EXIT (FAILED)\n");
         return;
 }
@@ -151,7 +151,7 @@ void ufs_free_blocks(struct inode *inode, u64 fragment, unsigned count)
                 goto failed;
         }
 
-        lock_ufs(sb);
+        mutex_lock(&UFS_SB(sb)->s_lock);
         
 do_more:
         overflow = 0;
@@ -211,12 +211,12 @@ do_more:
         }
 
         ufs_mark_sb_dirty(sb);
-        unlock_ufs(sb);
+        mutex_unlock(&UFS_SB(sb)->s_lock);
         UFSD("EXIT\n");
         return;
 
 failed_unlock:
-        unlock_ufs(sb);
+        mutex_unlock(&UFS_SB(sb)->s_lock);
 failed:
         UFSD("EXIT (FAILED)\n");
         return;
@@ -357,7 +357,7 @@ u64 ufs_new_fragments(struct inode *inode, void *p, u64 fragment,
         usb1 = ubh_get_usb_first(uspi);
         *err = -ENOSPC;
 
-        lock_ufs(sb);
+        mutex_lock(&UFS_SB(sb)->s_lock);
         tmp = ufs_data_ptr_to_cpu(sb, p);
 
         if (count + ufs_fragnum(fragment) > uspi->s_fpb) {
@@ -378,19 +378,19 @@ u64 ufs_new_fragments(struct inode *inode, void *p, u64 fragment,
                                   "fragment %llu, tmp %llu\n",
                                   (unsigned long long)fragment,
                                   (unsigned long long)tmp);
-                        unlock_ufs(sb);
+                        mutex_unlock(&UFS_SB(sb)->s_lock);
                         return INVBLOCK;
                 }
                 if (fragment < UFS_I(inode)->i_lastfrag) {
                         UFSD("EXIT (ALREADY ALLOCATED)\n");
-                        unlock_ufs(sb);
+                        mutex_unlock(&UFS_SB(sb)->s_lock);
                         return 0;
                 }
         }
         else {
                 if (tmp) {
                         UFSD("EXIT (ALREADY ALLOCATED)\n");
-                        unlock_ufs(sb);
+                        mutex_unlock(&UFS_SB(sb)->s_lock);
                         return 0;
                 }
         }
@@ -399,7 +399,7 @@ u64 ufs_new_fragments(struct inode *inode, void *p, u64 fragment,
          * There is not enough space for user on the device
          */
         if (!capable(CAP_SYS_RESOURCE) && ufs_freespace(uspi, UFS_MINFREE) <= 0) {
-                unlock_ufs(sb);
+                mutex_unlock(&UFS_SB(sb)->s_lock);
                 UFSD("EXIT (FAILED)\n");
                 return 0;
         }
@@ -424,7 +424,7 @@ u64 ufs_new_fragments(struct inode *inode, void *p, u64 fragment,
                         ufs_clear_frags(inode, result + oldcount,
                                         newcount - oldcount, locked_page != NULL);
                 }
-                unlock_ufs(sb);
+                mutex_unlock(&UFS_SB(sb)->s_lock);
                 UFSD("EXIT, result %llu\n", (unsigned long long)result);
                 return result;
         }
@@ -439,7 +439,7 @@ u64 ufs_new_fragments(struct inode *inode, void *p, u64 fragment,
                                                 fragment + count);
                 ufs_clear_frags(inode, result + oldcount, newcount - oldcount,
                                 locked_page != NULL);
-                unlock_ufs(sb);
+                mutex_unlock(&UFS_SB(sb)->s_lock);
                 UFSD("EXIT, result %llu\n", (unsigned long long)result);
                 return result;
         }
@@ -477,7 +477,7 @@ u64 ufs_new_fragments(struct inode *inode, void *p, u64 fragment,
                 *err = 0;
                 UFS_I(inode)->i_lastfrag = max(UFS_I(inode)->i_lastfrag,
                                                 fragment + count);
-                unlock_ufs(sb);
+                mutex_unlock(&UFS_SB(sb)->s_lock);
                 if (newcount < request)
                         ufs_free_fragments (inode, result + newcount, request - newcount);
                 ufs_free_fragments (inode, tmp, oldcount);
@@ -485,7 +485,7 @@ u64 ufs_new_fragments(struct inode *inode, void *p, u64 fragment,
                 return result;
         }
 
-        unlock_ufs(sb);
+        mutex_unlock(&UFS_SB(sb)->s_lock);
         UFSD("EXIT (FAILED)\n");
         return 0;
 }               
diff --git a/fs/ufs/ialloc.c b/fs/ufs/ialloc.c
index 7caa01652888..fd0203ce1f7f 100644
--- a/fs/ufs/ialloc.c
+++ b/fs/ufs/ialloc.c
@@ -69,11 +69,11 @@ void ufs_free_inode (struct inode * inode)
         
         ino = inode->i_ino;
 
-        lock_ufs(sb);
+        mutex_lock(&UFS_SB(sb)->s_lock);
 
         if (!((ino > 1) && (ino < (uspi->s_ncg * uspi->s_ipg )))) {
                 ufs_warning(sb, "ufs_free_inode", "reserved inode or nonexistent inode %u\n", ino);
-                unlock_ufs(sb);
+                mutex_unlock(&UFS_SB(sb)->s_lock);
                 return;
         }
         
@@ -81,7 +81,7 @@ void ufs_free_inode (struct inode * inode)
         bit = ufs_inotocgoff (ino);
         ucpi = ufs_load_cylinder (sb, cg);
         if (!ucpi) {
-                unlock_ufs(sb);
+                mutex_unlock(&UFS_SB(sb)->s_lock);
                 return;
         }
         ucg = ubh_get_ucg(UCPI_UBH(ucpi));
@@ -115,7 +115,7 @@ void ufs_free_inode (struct inode * inode)
                 ubh_sync_block(UCPI_UBH(ucpi));
         
         ufs_mark_sb_dirty(sb);
-        unlock_ufs(sb);
+        mutex_unlock(&UFS_SB(sb)->s_lock);
         UFSD("EXIT\n");
 }
 
@@ -193,7 +193,7 @@ struct inode *ufs_new_inode(struct inode *dir, umode_t mode)
         sbi = UFS_SB(sb);
         uspi = sbi->s_uspi;
 
-        lock_ufs(sb);
+        mutex_lock(&sbi->s_lock);
 
         /*
          * Try to place the inode in its parent directory
@@ -331,21 +331,21 @@ cg_found:
                         sync_dirty_buffer(bh);
                 brelse(bh);
         }
-        unlock_ufs(sb);
+        mutex_unlock(&sbi->s_lock);
 
         UFSD("allocating inode %lu\n", inode->i_ino);
         UFSD("EXIT\n");
         return inode;
 
 fail_remove_inode:
-        unlock_ufs(sb);
+        mutex_unlock(&sbi->s_lock);
         clear_nlink(inode);
         unlock_new_inode(inode);
         iput(inode);
         UFSD("EXIT (FAILED): err %d\n", err);
         return ERR_PTR(err);
 failed:
-        unlock_ufs(sb);
+        mutex_unlock(&sbi->s_lock);
         make_bad_inode(inode);
         iput (inode);
         UFSD("EXIT (FAILED): err %d\n", err);
diff --git a/fs/ufs/super.c b/fs/ufs/super.c
index b3bc3e7ae79d..afe9955654c8 100644
--- a/fs/ufs/super.c
+++ b/fs/ufs/super.c
@@ -694,6 +694,7 @@ static int ufs_sync_fs(struct super_block *sb, int wait)
         unsigned flags;
 
         lock_ufs(sb);
+        mutex_lock(&UFS_SB(sb)->s_lock);
 
         UFSD("ENTER\n");
 
@@ -711,6 +712,7 @@ static int ufs_sync_fs(struct super_block *sb, int wait)
         ufs_put_cstotal(sb);
 
         UFSD("EXIT\n");
+        mutex_unlock(&UFS_SB(sb)->s_lock);
         unlock_ufs(sb);
 
         return 0;
@@ -1277,6 +1279,7 @@ static int ufs_remount (struct super_block *sb, int *mount_flags, char *data)
 
         sync_filesystem(sb);
         lock_ufs(sb);
+        mutex_lock(&UFS_SB(sb)->s_lock);
         uspi = UFS_SB(sb)->s_uspi;
         flags = UFS_SB(sb)->s_flags;
         usb1 = ubh_get_usb_first(uspi);
@@ -1290,6 +1293,7 @@ static int ufs_remount (struct super_block *sb, int *mount_flags, char *data)
         new_mount_opt = 0;
         ufs_set_opt (new_mount_opt, ONERROR_LOCK);
         if (!ufs_parse_options (data, &new_mount_opt)) {
+                mutex_unlock(&UFS_SB(sb)->s_lock);
                 unlock_ufs(sb);
                 return -EINVAL;
         }
@@ -1297,12 +1301,14 @@ static int ufs_remount (struct super_block *sb, int *mount_flags, char *data)
                 new_mount_opt |= ufstype;
         } else if ((new_mount_opt & UFS_MOUNT_UFSTYPE) != ufstype) {
                 pr_err("ufstype can't be changed during remount\n");
+                mutex_unlock(&UFS_SB(sb)->s_lock);
                 unlock_ufs(sb);
                 return -EINVAL;
         }
 
         if ((*mount_flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) {
                 UFS_SB(sb)->s_mount_opt = new_mount_opt;
+                mutex_unlock(&UFS_SB(sb)->s_lock);
                 unlock_ufs(sb);
                 return 0;
         }
@@ -1326,6 +1332,7 @@ static int ufs_remount (struct super_block *sb, int *mount_flags, char *data)
          */
 #ifndef CONFIG_UFS_FS_WRITE
                 pr_err("ufs was compiled with read-only support, can't be mounted as read-write\n");
+                mutex_unlock(&UFS_SB(sb)->s_lock);
                 unlock_ufs(sb);
                 return -EINVAL;
 #else
@@ -1335,11 +1342,13 @@ static int ufs_remount (struct super_block *sb, int *mount_flags, char *data)
                     ufstype != UFS_MOUNT_UFSTYPE_SUNx86 &&
                     ufstype != UFS_MOUNT_UFSTYPE_UFS2) {
                         pr_err("this ufstype is read-only supported\n");
+                        mutex_unlock(&UFS_SB(sb)->s_lock);
                         unlock_ufs(sb);
                         return -EINVAL;
                 }
                 if (!ufs_read_cylinder_structures(sb)) {
                         pr_err("failed during remounting\n");
+                        mutex_unlock(&UFS_SB(sb)->s_lock);
                         unlock_ufs(sb);
                         return -EPERM;
                 }
@@ -1347,6 +1356,7 @@ static int ufs_remount (struct super_block *sb, int *mount_flags, char *data)
 #endif
         }
         UFS_SB(sb)->s_mount_opt = new_mount_opt;
+        mutex_unlock(&UFS_SB(sb)->s_lock);
         unlock_ufs(sb);
         return 0;
 }
diff --git a/fs/ufs/ufs.h b/fs/ufs/ufs.h
index 2a07396d5f9e..cf6368d42d4a 100644
--- a/fs/ufs/ufs.h
+++ b/fs/ufs/ufs.h
@@ -30,6 +30,7 @@ struct ufs_sb_info {
         int work_queued; /* non-zero if the delayed work is queued */
         struct delayed_work sync_work; /* FS sync delayed work */
         spinlock_t work_lock; /* protects sync_work and work_queued */
+        struct mutex s_lock;
 };
 
 struct ufs_inode_info {