xfs: unlock i_mutex in xfs_break_layouts

We want to drop all I/O path locks when recalling layouts, and that includes
i_mutex for the write path.  Without this we get stuck processe when recalls
take too long.

[dchinner: fix build with !CONFIG_PNFS]

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>

5 files changed, 13 insertions, 7 deletions

diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index edeaccc7961a..f63aeddd31d5 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -555,7 +555,7 @@ restart:
         if (error)
                 return error;
 
-        error = xfs_break_layouts(inode, iolock);
+        error = xfs_break_layouts(inode, iolock, true);
         if (error)
                 return error;
 
@@ -842,7 +842,7 @@ xfs_file_fallocate(
                 return -EOPNOTSUPP;
 
         xfs_ilock(ip, iolock);
-        error = xfs_break_layouts(inode, &iolock);
+        error = xfs_break_layouts(inode, &iolock, false);
         if (error)
                 goto out_unlock;
 
diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
index ac4feae45eb3..3a21cc71fda0 100644
--- a/fs/xfs/xfs_ioctl.c
+++ b/fs/xfs/xfs_ioctl.c
@@ -639,7 +639,7 @@ xfs_ioc_space(
                 return error;
 
         xfs_ilock(ip, iolock);
-        error = xfs_break_layouts(inode, &iolock);
+        error = xfs_break_layouts(inode, &iolock, false);
         if (error)
                 goto out_unlock;
 
diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
index d7782ae1af3c..1d4efee4be17 100644
--- a/fs/xfs/xfs_iops.c
+++ b/fs/xfs/xfs_iops.c
@@ -988,7 +988,7 @@ xfs_vn_setattr(
                 uint            iolock = XFS_IOLOCK_EXCL;
 
                 xfs_ilock(ip, iolock);
-                error = xfs_break_layouts(dentry->d_inode, &iolock);
+                error = xfs_break_layouts(dentry->d_inode, &iolock, true);
                 if (!error)
                         error = xfs_setattr_size(ip, iattr);
                 xfs_iunlock(ip, iolock);
diff --git a/fs/xfs/xfs_pnfs.c b/fs/xfs/xfs_pnfs.c
index 4b33ef112400..cbb424f4d93a 100644
--- a/fs/xfs/xfs_pnfs.c
+++ b/fs/xfs/xfs_pnfs.c
@@ -31,7 +31,8 @@
 int
 xfs_break_layouts(
         struct inode            *inode,
-        uint                    *iolock)
+        uint                    *iolock,
+        bool                    with_imutex)
 {
         struct xfs_inode        *ip = XFS_I(inode);
         int                     error;
@@ -40,8 +41,12 @@ xfs_break_layouts(
 
         while ((error = break_layout(inode, false) == -EWOULDBLOCK)) {
                 xfs_iunlock(ip, *iolock);
+                if (with_imutex && (*iolock & XFS_IOLOCK_EXCL))
+                        mutex_unlock(&inode->i_mutex);
                 error = break_layout(inode, true);
                 *iolock = XFS_IOLOCK_EXCL;
+                if (with_imutex)
+                        mutex_lock(&inode->i_mutex);
                 xfs_ilock(ip, *iolock);
         }
 
diff --git a/fs/xfs/xfs_pnfs.h b/fs/xfs/xfs_pnfs.h
index b7fbfce660f6..8147ac108820 100644
--- a/fs/xfs/xfs_pnfs.h
+++ b/fs/xfs/xfs_pnfs.h
@@ -8,9 +8,10 @@ int xfs_fs_map_blocks(struct inode *inode, loff_t offset, u64 length,
 int xfs_fs_commit_blocks(struct inode *inode, struct iomap *maps, int nr_maps,
                 struct iattr *iattr);
 
-int xfs_break_layouts(struct inode *inode, uint *iolock);
+int xfs_break_layouts(struct inode *inode, uint *iolock, bool with_imutex);
 #else
-static inline int xfs_break_layouts(struct inode *inode, uint *iolock)
+static inline int
+xfs_break_layouts(struct inode *inode, uint *iolock, bool with_imutex)
 {
         return 0;
 }