Revert "ext4: fix suboptimal seek_{data,hole} extents traversial"
This reverts commit 14516bb7bb6ffbd49f35389f9ece3b2045ba5815.
This was causing regression test failures with generic/285 with an ext3
filesystem using CONFIG_EXT4_USE_FOR_EXT23.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index 513c12c..8131be8 100644
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -273,19 +273,24 @@
* we determine this extent as a data or a hole according to whether the
* page cache has data or not.
*/
-static int ext4_find_unwritten_pgoff(struct inode *inode, int whence,
- loff_t endoff, loff_t *offset)
+static int ext4_find_unwritten_pgoff(struct inode *inode,
+ int whence,
+ struct ext4_map_blocks *map,
+ loff_t *offset)
{
struct pagevec pvec;
+ unsigned int blkbits;
pgoff_t index;
pgoff_t end;
+ loff_t endoff;
loff_t startoff;
loff_t lastoff;
int found = 0;
+ blkbits = inode->i_sb->s_blocksize_bits;
startoff = *offset;
lastoff = startoff;
-
+ endoff = (loff_t)(map->m_lblk + map->m_len) << blkbits;
index = startoff >> PAGE_CACHE_SHIFT;
end = endoff >> PAGE_CACHE_SHIFT;
@@ -403,144 +408,147 @@
static loff_t ext4_seek_data(struct file *file, loff_t offset, loff_t maxsize)
{
struct inode *inode = file->f_mapping->host;
- struct fiemap_extent_info fie;
- struct fiemap_extent ext[2];
- loff_t next;
- int i, ret = 0;
+ struct ext4_map_blocks map;
+ struct extent_status es;
+ ext4_lblk_t start, last, end;
+ loff_t dataoff, isize;
+ int blkbits;
+ int ret = 0;
mutex_lock(&inode->i_mutex);
- if (offset >= inode->i_size) {
+
+ isize = i_size_read(inode);
+ if (offset >= isize) {
mutex_unlock(&inode->i_mutex);
return -ENXIO;
}
- fie.fi_flags = 0;
- fie.fi_extents_max = 2;
- fie.fi_extents_start = (struct fiemap_extent __user *) &ext;
- while (1) {
- mm_segment_t old_fs = get_fs();
- fie.fi_extents_mapped = 0;
- memset(ext, 0, sizeof(*ext) * fie.fi_extents_max);
+ blkbits = inode->i_sb->s_blocksize_bits;
+ start = offset >> blkbits;
+ last = start;
+ end = isize >> blkbits;
+ dataoff = offset;
- set_fs(get_ds());
- ret = ext4_fiemap(inode, &fie, offset, maxsize - offset);
- set_fs(old_fs);
- if (ret)
- break;
-
- /* No extents found, EOF */
- if (!fie.fi_extents_mapped) {
- ret = -ENXIO;
+ do {
+ map.m_lblk = last;
+ map.m_len = end - last + 1;
+ ret = ext4_map_blocks(NULL, inode, &map, 0);
+ if (ret > 0 && !(map.m_flags & EXT4_MAP_UNWRITTEN)) {
+ if (last != start)
+ dataoff = (loff_t)last << blkbits;
break;
}
- for (i = 0; i < fie.fi_extents_mapped; i++) {
- next = (loff_t)(ext[i].fe_length + ext[i].fe_logical);
- if (offset < (loff_t)ext[i].fe_logical)
- offset = (loff_t)ext[i].fe_logical;
- /*
- * If extent is not unwritten, then it contains valid
- * data, mapped or delayed.
- */
- if (!(ext[i].fe_flags & FIEMAP_EXTENT_UNWRITTEN))
- goto out;
-
- /*
- * If there is a unwritten extent at this offset,
- * it will be as a data or a hole according to page
- * cache that has data or not.
- */
- if (ext4_find_unwritten_pgoff(inode, SEEK_DATA,
- next, &offset))
- goto out;
-
- if (ext[i].fe_flags & FIEMAP_EXTENT_LAST) {
- ret = -ENXIO;
- goto out;
- }
- offset = next;
+ /*
+ * If there is a delay extent at this offset,
+ * it will be as a data.
+ */
+ ext4_es_find_delayed_extent_range(inode, last, last, &es);
+ if (es.es_len != 0 && in_range(last, es.es_lblk, es.es_len)) {
+ if (last != start)
+ dataoff = (loff_t)last << blkbits;
+ break;
}
- }
- if (offset > inode->i_size)
- offset = inode->i_size;
-out:
+
+ /*
+ * If there is a unwritten extent at this offset,
+ * it will be as a data or a hole according to page
+ * cache that has data or not.
+ */
+ if (map.m_flags & EXT4_MAP_UNWRITTEN) {
+ int unwritten;
+ unwritten = ext4_find_unwritten_pgoff(inode, SEEK_DATA,
+ &map, &dataoff);
+ if (unwritten)
+ break;
+ }
+
+ last++;
+ dataoff = (loff_t)last << blkbits;
+ } while (last <= end);
+
mutex_unlock(&inode->i_mutex);
- if (ret)
- return ret;
- return vfs_setpos(file, offset, maxsize);
+ if (dataoff > isize)
+ return -ENXIO;
+
+ return vfs_setpos(file, dataoff, maxsize);
}
/*
- * ext4_seek_hole() retrieves the offset for SEEK_HOLE
+ * ext4_seek_hole() retrieves the offset for SEEK_HOLE.
*/
static loff_t ext4_seek_hole(struct file *file, loff_t offset, loff_t maxsize)
{
struct inode *inode = file->f_mapping->host;
- struct fiemap_extent_info fie;
- struct fiemap_extent ext[2];
- loff_t next;
- int i, ret = 0;
+ struct ext4_map_blocks map;
+ struct extent_status es;
+ ext4_lblk_t start, last, end;
+ loff_t holeoff, isize;
+ int blkbits;
+ int ret = 0;
mutex_lock(&inode->i_mutex);
- if (offset >= inode->i_size) {
+
+ isize = i_size_read(inode);
+ if (offset >= isize) {
mutex_unlock(&inode->i_mutex);
return -ENXIO;
}
- fie.fi_flags = 0;
- fie.fi_extents_max = 2;
- fie.fi_extents_start = (struct fiemap_extent __user *)&ext;
- while (1) {
- mm_segment_t old_fs = get_fs();
+ blkbits = inode->i_sb->s_blocksize_bits;
+ start = offset >> blkbits;
+ last = start;
+ end = isize >> blkbits;
+ holeoff = offset;
- fie.fi_extents_mapped = 0;
- memset(ext, 0, sizeof(*ext));
+ do {
+ map.m_lblk = last;
+ map.m_len = end - last + 1;
+ ret = ext4_map_blocks(NULL, inode, &map, 0);
+ if (ret > 0 && !(map.m_flags & EXT4_MAP_UNWRITTEN)) {
+ last += ret;
+ holeoff = (loff_t)last << blkbits;
+ continue;
+ }
- set_fs(get_ds());
- ret = ext4_fiemap(inode, &fie, offset, maxsize - offset);
- set_fs(old_fs);
- if (ret)
- break;
+ /*
+ * If there is a delay extent at this offset,
+ * we will skip this extent.
+ */
+ ext4_es_find_delayed_extent_range(inode, last, last, &es);
+ if (es.es_len != 0 && in_range(last, es.es_lblk, es.es_len)) {
+ last = es.es_lblk + es.es_len;
+ holeoff = (loff_t)last << blkbits;
+ continue;
+ }
- /* No extents found */
- if (!fie.fi_extents_mapped)
- break;
-
- for (i = 0; i < fie.fi_extents_mapped; i++) {
- next = (loff_t)(ext[i].fe_logical + ext[i].fe_length);
- /*
- * If extent is not unwritten, then it contains valid
- * data, mapped or delayed.
- */
- if (!(ext[i].fe_flags & FIEMAP_EXTENT_UNWRITTEN)) {
- if (offset < (loff_t)ext[i].fe_logical)
- goto out;
- offset = next;
+ /*
+ * If there is a unwritten extent at this offset,
+ * it will be as a data or a hole according to page
+ * cache that has data or not.
+ */
+ if (map.m_flags & EXT4_MAP_UNWRITTEN) {
+ int unwritten;
+ unwritten = ext4_find_unwritten_pgoff(inode, SEEK_HOLE,
+ &map, &holeoff);
+ if (!unwritten) {
+ last += ret;
+ holeoff = (loff_t)last << blkbits;
continue;
}
- /*
- * If there is a unwritten extent at this offset,
- * it will be as a data or a hole according to page
- * cache that has data or not.
- */
- if (ext4_find_unwritten_pgoff(inode, SEEK_HOLE,
- next, &offset))
- goto out;
-
- offset = next;
- if (ext[i].fe_flags & FIEMAP_EXTENT_LAST)
- goto out;
}
- }
- if (offset > inode->i_size)
- offset = inode->i_size;
-out:
- mutex_unlock(&inode->i_mutex);
- if (ret)
- return ret;
- return vfs_setpos(file, offset, maxsize);
+ /* find a hole */
+ break;
+ } while (last <= end);
+
+ mutex_unlock(&inode->i_mutex);
+
+ if (holeoff > isize)
+ holeoff = isize;
+
+ return vfs_setpos(file, holeoff, maxsize);
}
/*