ext4: Handle -EDQUOT error on write

We need to release the journal before we do a write_inode.  Otherwise
we could deadlock.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>

1 files changed, 18 insertions, 14 deletions

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index c818972c8302..60b3a19e9927 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -1835,24 +1835,12 @@ repeat:
          * later. Real quota accounting is done at pages writeout
          * time.
          */
-        if (vfs_dq_reserve_block(inode, md_needed + 1)) {
-                /* 
-                 * We tend to badly over-estimate the amount of
-                 * metadata blocks which are needed, so if we have
-                 * reserved any metadata blocks, try to force out the
-                 * inode and see if we have any better luck.
-                 */
-                if (md_reserved && retries++ <= 3)
-                        goto retry;
+        if (vfs_dq_reserve_block(inode, md_needed + 1))
                 return -EDQUOT;
-        }
 
         if (ext4_claim_free_blocks(sbi, md_needed + 1)) {
                 vfs_dq_release_reservation_block(inode, md_needed + 1);
                 if (ext4_should_retry_alloc(inode->i_sb, &retries)) {
-                retry:
-                        if (md_reserved)
-                                write_inode_now(inode, (retries == 3));
                         yield();
                         goto repeat;
                 }
@@ -3032,7 +3020,7 @@ static int ext4_da_write_begin(struct file *file, struct address_space *mapping,
                                loff_t pos, unsigned len, unsigned flags,
                                struct page **pagep, void **fsdata)
 {
-        int ret, retries = 0;
+        int ret, retries = 0, quota_retries = 0;
         struct page *page;
         pgoff_t index;
         unsigned from, to;
@@ -3091,6 +3079,22 @@ retry:
 
         if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
                 goto retry;
+
+        if ((ret == -EDQUOT) &&
+            EXT4_I(inode)->i_reserved_meta_blocks &&
+            (quota_retries++ < 3)) {
+                /*
+                 * Since we often over-estimate the number of meta
+                 * data blocks required, we may sometimes get a
+                 * spurios out of quota error even though there would
+                 * be enough space once we write the data blocks and
+                 * find out how many meta data blocks were _really_
+                 * required.  So try forcing the inode write to see if
+                 * that helps.
+                 */
+                write_inode_now(inode, (quota_retries == 3));
+                goto retry;
+        }
 out:
         return ret;
 }