[PATCH] xfs: unlock i_mutex in xfs_break_layouts

[Christoph Hellwig <hch@xxxxxx>]

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.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
 fs/xfs/xfs_file.c  | 4 ++--
 fs/xfs/xfs_ioctl.c | 2 +-
 fs/xfs/xfs_iops.c  | 2 +-
 fs/xfs/xfs_pnfs.c  | 7 ++++++-
 fs/xfs/xfs_pnfs.h  | 2 +-
 5 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index a2e1cb8..963dfb2 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -559,7 +559,7 @@ restart:
        if (error)
                return error;
 
-       error = xfs_break_layouts(inode, iolock);
+       error = xfs_break_layouts(inode, iolock, true);
        if (error)
                return error;
 
@@ -843,7 +843,7 @@ 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 ac4feae..3a21cc7 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 e53a903..79520c7 100644
--- a/fs/xfs/xfs_iops.c
+++ b/fs/xfs/xfs_iops.c
@@ -975,7 +975,7 @@ 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 365dd57..981a657 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 b7fbfce..f749475 100644
--- a/fs/xfs/xfs_pnfs.h
+++ b/fs/xfs/xfs_pnfs.h
@@ -8,7 +8,7 @@ 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)
 {
-- 
1.9.1