[GFS2] Quotas non-functional - fix another bug

This patch fixes a bug where gfs2 was writing update quota usage
information to the wrong location in the quota file.

Signed-off-by: Abhijith Das <adas@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

2 files changed, 17 insertions, 4 deletions

diff --git a/fs/gfs2/ondisk.c b/fs/gfs2/ondisk.c
index cd4cf055c37d..a5b05ea3d4c7 100644
--- a/fs/gfs2/ondisk.c
+++ b/fs/gfs2/ondisk.c
@@ -121,6 +121,16 @@ void gfs2_quota_in(struct gfs2_quota_host *qu, const void *buf)
         qu->qu_value = be64_to_cpu(str->qu_value);
 }
 
+void gfs2_quota_out(const struct gfs2_quota_host *qu, void *buf)
+{
+        struct gfs2_quota *str = buf;
+
+        str->qu_limit = cpu_to_be64(qu->qu_limit);
+        str->qu_warn = cpu_to_be64(qu->qu_warn);
+        str->qu_value = cpu_to_be64(qu->qu_value);
+        memset(&str->qu_reserved, 0, sizeof(str->qu_reserved));
+}
+
 void gfs2_dinode_out(const struct gfs2_inode *ip, void *buf)
 {
         const struct gfs2_dinode_host *di = &ip->i_di;
diff --git a/fs/gfs2/quota.c b/fs/gfs2/quota.c
index fcd3ee2c5b96..8a58815dea08 100644
--- a/fs/gfs2/quota.c
+++ b/fs/gfs2/quota.c
@@ -573,12 +573,13 @@ static int gfs2_adjust_quota(struct gfs2_inode *ip, loff_t loc,
         struct inode *inode = &ip->i_inode;
         struct address_space *mapping = inode->i_mapping;
         unsigned long index = loc >> PAGE_CACHE_SHIFT;
-        unsigned offset = loc & (PAGE_CACHE_SHIFT - 1);
+        unsigned offset = loc & (PAGE_CACHE_SIZE - 1);
         unsigned blocksize, iblock, pos;
         struct buffer_head *bh;
         struct page *page;
         void *kaddr;
-        __be64 *ptr;
+        char *ptr;
+        struct gfs2_quota_host qp;
         s64 value;
         int err = -EIO;
 
@@ -620,8 +621,10 @@ static int gfs2_adjust_quota(struct gfs2_inode *ip, loff_t loc,
 
         kaddr = kmap_atomic(page, KM_USER0);
         ptr = kaddr + offset;
-        value = (s64)be64_to_cpu(*ptr) + change;
-        *ptr = cpu_to_be64(value);
+        gfs2_quota_in(&qp, ptr);
+        qp.qu_value += change;
+        value = qp.qu_value;
+        gfs2_quota_out(&qp, ptr);
         flush_dcache_page(page);
         kunmap_atomic(kaddr, KM_USER0);
         err = 0;