ext4: move i_size,i_disksize update routines to helper function

Cc: stable@vger.kernel.org # needed for bug fix patches
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 4d95c330177513a432a7e6b9dffd5c3d9a4ff7f3..b0c225cdb52cd20ba5927149c338d9749e951f57 100644 (file)
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -2454,6 +2454,22 @@ static inline void ext4_update_i_disksize(struct inode *inode, loff_t newsize)
        up_write(&EXT4_I(inode)->i_data_sem);
 }
 
+/* Update i_size, i_disksize. Requires i_mutex to avoid races with truncate */
+static inline int ext4_update_inode_size(struct inode *inode, loff_t newsize)
+{
+       int changed = 0;
+
+       if (newsize > inode->i_size) {
+               i_size_write(inode, newsize);
+               changed = 1;
+       }
+       if (newsize > EXT4_I(inode)->i_disksize) {
+               ext4_update_i_disksize(inode, newsize);
+               changed |= 2;
+       }
+       return changed;
+}
+
 struct ext4_group_info {
        unsigned long   bb_state;
        struct rb_root  bb_free_root;

diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 76c2df382b7d05619bbe4093d2115ca6dafa617e..f0e6934291dd2ff592644aa5d4fe1c8c866e37f7 100644 (file)
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -4839,12 +4839,8 @@ static long ext4_zero_range(struct file *file, loff_t offset,
        }
 
        inode->i_mtime = inode->i_ctime = ext4_current_time(inode);
-
        if (new_size) {
-               if (new_size > i_size_read(inode))
-                       i_size_write(inode, new_size);
-               if (new_size > EXT4_I(inode)->i_disksize)
-                       ext4_update_i_disksize(inode, new_size);
+               ext4_update_inode_size(inode, new_size);
        } else {
                /*
                * Mark that we allocate beyond EOF so the subsequent truncate
@@ -4886,7 +4882,6 @@ long ext4_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
        int ret = 0;
        int flags;
        ext4_lblk_t lblk;
-       struct timespec tv;
        unsigned int blkbits = inode->i_blkbits;
 
        /* Return error if mode is not supported */
@@ -4945,15 +4940,11 @@ long ext4_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
        if (IS_ERR(handle))
                goto out;
 
-       tv = inode->i_ctime = ext4_current_time(inode);
+       inode->i_ctime = ext4_current_time(inode);
 
        if (new_size) {
-               if (new_size > i_size_read(inode)) {
-                       i_size_write(inode, new_size);
-                       inode->i_mtime = tv;
-               }
-               if (new_size > EXT4_I(inode)->i_disksize)
-                       ext4_update_i_disksize(inode, new_size);
+               if (ext4_update_inode_size(inode, new_size) & 0x1)
+                       inode->i_mtime = inode->i_ctime;
        } else {
                /*
                * Mark that we allocate beyond EOF so the subsequent truncate

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 367a60c07cf034e6983d8a51cf0eb321394b6209..b1ddd93526445ccc31067486760869adba3923e3 100644 (file)
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -1055,27 +1055,11 @@ static int ext4_write_end(struct file *file,
        } else
                copied = block_write_end(file, mapping, pos,
                                         len, copied, page, fsdata);
-
        /*
-        * No need to use i_size_read() here, the i_size
-        * cannot change under us because we hole i_mutex.
-        *
-        * But it's important to update i_size while still holding page lock:
+        * it's important to update i_size while still holding page lock:
         * page writeout could otherwise come in and zero beyond i_size.
         */
-       if (pos + copied > inode->i_size) {
-               i_size_write(inode, pos + copied);
-               i_size_changed = 1;
-       }
-
-       if (pos + copied > EXT4_I(inode)->i_disksize) {
-               /* We need to mark inode dirty even if
-                * new_i_size is less that inode->i_size
-                * but greater than i_disksize. (hint delalloc)
-                */
-               ext4_update_i_disksize(inode, (pos + copied));
-               i_size_changed = 1;
-       }
+       i_size_changed = ext4_update_inode_size(inode, pos + copied);
        unlock_page(page);
        page_cache_release(page);
 
@@ -1123,7 +1107,7 @@ static int ext4_journalled_write_end(struct file *file,
        int ret = 0, ret2;
        int partial = 0;
        unsigned from, to;
-       loff_t new_i_size;
+       int size_changed = 0;
 
        trace_ext4_journalled_write_end(inode, pos, len, copied);
        from = pos & (PAGE_CACHE_SIZE - 1);
@@ -1146,20 +1130,18 @@ static int ext4_journalled_write_end(struct file *file,
                if (!partial)
                        SetPageUptodate(page);
        }
-       new_i_size = pos + copied;
-       if (new_i_size > inode->i_size)
-               i_size_write(inode, pos+copied);
+       size_changed = ext4_update_inode_size(inode, pos + copied);
        ext4_set_inode_state(inode, EXT4_STATE_JDATA);
        EXT4_I(inode)->i_datasync_tid = handle->h_transaction->t_tid;
-       if (new_i_size > EXT4_I(inode)->i_disksize) {
-               ext4_update_i_disksize(inode, new_i_size);
+       unlock_page(page);
+       page_cache_release(page);
+
+       if (size_changed) {
                ret2 = ext4_mark_inode_dirty(handle, inode);
                if (!ret)
                        ret = ret2;
        }
 
-       unlock_page(page);
-       page_cache_release(page);
        if (pos + len > inode->i_size && ext4_can_truncate(inode))
                /* if we have allocated more blocks and copied
                 * less. We will have blocks allocated outside