1 files changed, 35 insertions, 14 deletions

diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 4e2bdc26b85c..ca62d748cc65 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -3688,6 +3688,7 @@ static int ext4_ext_fiemap_cb(struct inode *inode, struct ext4_ext_path *path,
                 pgoff_t         last_offset;
                 pgoff_t         offset;
                 pgoff_t         index;
+                pgoff_t         start_index = 0;
                 struct page     **pages = NULL;
                 struct buffer_head *bh = NULL;
                 struct buffer_head *head = NULL;
@@ -3714,39 +3715,57 @@ out:
                                 kfree(pages);
                                 return EXT_CONTINUE;
                         }
+                        index = 0;
 
+next_page:
                         /* Try to find the 1st mapped buffer. */
-                        end = ((__u64)pages[0]->index << PAGE_SHIFT) >>
+                        end = ((__u64)pages[index]->index << PAGE_SHIFT) >>
                                   blksize_bits;
-                        if (!page_has_buffers(pages[0]))
+                        if (!page_has_buffers(pages[index]))
                                 goto out;
-                        head = page_buffers(pages[0]);
+                        head = page_buffers(pages[index]);
                         if (!head)
                                 goto out;
 
+                        index++;
                         bh = head;
                         do {
-                                if (buffer_mapped(bh)) {
+                                if (end >= newex->ec_block +
+                                        newex->ec_len)
+                                        /* The buffer is out of
+                                         * the request range.
+                                         */
+                                        goto out;
+
+                                if (buffer_mapped(bh) &&
+                                    end >= newex->ec_block) {
+                                        start_index = index - 1;
                                         /* get the 1st mapped buffer. */
-                                        if (end > newex->ec_block +
-                                                newex->ec_len)
-                                                /* The buffer is out of
-                                                 * the request range.
-                                                 */
-                                                goto out;
                                         goto found_mapped_buffer;
                                 }
+
                                 bh = bh->b_this_page;
                                 end++;
                         } while (bh != head);
 
-                        /* No mapped buffer found. */
-                        goto out;
+                        /* No mapped buffer in the range found in this page,
+                         * We need to look up next page.
+                         */
+                        if (index >= ret) {
+                                /* There is no page left, but we need to limit
+                                 * newex->ec_len.
+                                 */
+                                newex->ec_len = end - newex->ec_block;
+                                goto out;
+                        }
+                        goto next_page;
                 } else {
                         /*Find contiguous delayed buffers. */
                         if (ret > 0 && pages[0]->index == last_offset)
                                 head = page_buffers(pages[0]);
                         bh = head;
+                        index = 1;
+                        start_index = 0;
                 }
 
 found_mapped_buffer:
@@ -3769,7 +3788,7 @@ found_mapped_buffer:
                                 end++;
                         } while (bh != head);
 
-                        for (index = 1; index < ret; index++) {
+                        for (; index < ret; index++) {
                                 if (!page_has_buffers(pages[index])) {
                                         bh = NULL;
                                         break;
@@ -3779,8 +3798,10 @@ found_mapped_buffer:
                                         bh = NULL;
                                         break;
                                 }
+
                                 if (pages[index]->index !=
-                                        pages[0]->index + index) {
+                                    pages[start_index]->index + index
+                                    - start_index) {
                                         /* Blocks are not contiguous. */
                                         bh = NULL;
                                         break;