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Date: Tue, 19 Apr 2011 00:41:23 -0700
From: Allison Henderson <achender@...ux.vnet.ibm.com>
To: linux-ext4@...r.kernel.org
Subject: [Ext4 punch hole 2/6 v5] Ext4 Punch Hole Support: Split Extents
The ext4_split_unwritten_extents routine has been modified
to also handle initialized extents and renamed to
ext4_ext_split_extents. This routine is used to split
an extent that needs to be partially converted to
an uninitialized extent.
Signed-off-by: Allison Henderson <achender@...ibm.com>
---
:100644 100644 6c1f415... a256ba3... M fs/ext4/ext4.h
:100644 100644 0b186d9... 4d9f06d... M fs/ext4/extents.c
fs/ext4/ext4.h | 5 ++++
fs/ext4/extents.c | 63 +++++++++++++++++++++++++++++++++++++++++-----------
2 files changed, 54 insertions(+), 14 deletions(-)
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 6c1f415..a256ba3 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -516,6 +516,11 @@ struct ext4_new_group_data {
#define EXT4_GET_BLOCKS_PUNCH_OUT_EXT 0x0020
/*
+ * Flags used by ext4_ext_split_extents
+ */
+#define EXT4_SPLIT_EXTENTS_UNWRITTEN 0x0001
+
+/*
* Flags used by ext4_free_blocks
*/
#define EXT4_FREE_BLOCKS_METADATA 0x0001
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 0b186d9..4d9f06d 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -46,6 +46,13 @@
#include <trace/events/ext4.h>
+static int ext4_ext_split_extents(handle_t *handle,
+ struct inode *inode,
+ struct ext4_map_blocks *map,
+ struct ext4_ext_path *path,
+ int map_blocks_flags,
+ int split_flags);
+
static int ext4_ext_truncate_extend_restart(handle_t *handle,
struct inode *inode,
int needed)
@@ -2868,13 +2875,27 @@ fix_extent_len:
* being filled will be convert to initialized by the end_io callback function
* via ext4_convert_unwritten_extents().
*
+ * @handle: The journal handle
+ * @inode: The files inode
+ * @map: Map structure that specifies
+ * which blocks need to be split out
+ * @path: The path to the extent
+ * @map_blocks_flags: Get blocks flags used to insert the new extent
+ * @split_flags: Optional split extents flag that may be used
+ *
+ * EXT4_SPLIT_EXTENTS_UNWRITTEN:
+ * Used to split unwriten extents. The extents
+ * that are split will be set to unwritten, or
+ * zero'd out if the split fails
+ *
* Returns the size of uninitialized extent to be written on success.
*/
-static int ext4_split_unwritten_extents(handle_t *handle,
+static int ext4_ext_split_extents(handle_t *handle,
struct inode *inode,
struct ext4_map_blocks *map,
struct ext4_ext_path *path,
- int flags)
+ int map_blocks_flags,
+ int split_flags)
{
struct ext4_extent *ex, newex, orig_ex;
struct ext4_extent *ex1 = NULL;
@@ -2885,8 +2906,9 @@ static int ext4_split_unwritten_extents(handle_t *handle,
ext4_fsblk_t newblock;
int err = 0;
int may_zeroout;
+ int uninitialized = 0;
- ext_debug("ext4_split_unwritten_extents: inode %lu, logical"
+ ext_debug("ext4_ext_split_extents: inode %lu, logical"
"block %llu, max_blocks %u\n", inode->i_ino,
(unsigned long long)map->m_lblk, map->m_len);
@@ -2902,6 +2924,9 @@ static int ext4_split_unwritten_extents(handle_t *handle,
allocated = ee_len - (map->m_lblk - ee_block);
newblock = map->m_lblk - ee_block + ext4_ext_pblock(ex);
+ uninitialized = split_flags & EXT4_SPLIT_EXTENTS_UNWRITTEN ?
+ 1 : ext4_ext_is_uninitialized(ex);
+
ex2 = ex;
orig_ex.ee_block = ex->ee_block;
orig_ex.ee_len = cpu_to_le16(ee_len);
@@ -2911,7 +2936,8 @@ static int ext4_split_unwritten_extents(handle_t *handle,
* It is safe to convert extent to initialized via explicit
* zeroout only if extent is fully insde i_size or new_size.
*/
- may_zeroout = ee_block + ee_len <= eof_block;
+ may_zeroout = split_flags & EXT4_SPLIT_EXTENTS_UNWRITTEN ?
+ ee_block + ee_len <= eof_block : 0;
/*
* If the uninitialized extent begins at the same logical
@@ -2928,7 +2954,8 @@ static int ext4_split_unwritten_extents(handle_t *handle,
if (map->m_lblk > ee_block) {
ex1 = ex;
ex1->ee_len = cpu_to_le16(map->m_lblk - ee_block);
- ext4_ext_mark_uninitialized(ex1);
+ if (uninitialized)
+ ext4_ext_mark_uninitialized(ex1);
ex2 = &newex;
}
/*
@@ -2945,8 +2972,10 @@ static int ext4_split_unwritten_extents(handle_t *handle,
ex3->ee_block = cpu_to_le32(map->m_lblk + map->m_len);
ext4_ext_store_pblock(ex3, newblock + map->m_len);
ex3->ee_len = cpu_to_le16(allocated - map->m_len);
- ext4_ext_mark_uninitialized(ex3);
- err = ext4_ext_insert_extent(handle, inode, path, ex3, flags);
+ if (uninitialized)
+ ext4_ext_mark_uninitialized(ex3);
+ err = ext4_ext_insert_extent(handle, inode, path, ex3,
+ map_blocks_flags);
if (err == -ENOSPC && may_zeroout) {
err = ext4_ext_zeroout(inode, &orig_ex);
if (err)
@@ -2973,7 +3002,8 @@ static int ext4_split_unwritten_extents(handle_t *handle,
*/
ee_len -= ext4_ext_get_actual_len(ex3);
orig_ex.ee_len = cpu_to_le16(ee_len);
- may_zeroout = ee_block + ee_len <= eof_block;
+ may_zeroout = split_flags & EXT4_SPLIT_EXTENTS_UNWRITTEN ?
+ ee_block + ee_len <= eof_block : 0;
depth = newdepth;
ext4_ext_drop_refs(path);
@@ -3000,7 +3030,8 @@ static int ext4_split_unwritten_extents(handle_t *handle,
if (ex1 && ex1 != ex) {
ex1 = ex;
ex1->ee_len = cpu_to_le16(map->m_lblk - ee_block);
- ext4_ext_mark_uninitialized(ex1);
+ if (uninitialized)
+ ext4_ext_mark_uninitialized(ex1);
ex2 = &newex;
}
/*
@@ -3010,7 +3041,8 @@ static int ext4_split_unwritten_extents(handle_t *handle,
ex2->ee_block = cpu_to_le32(map->m_lblk);
ext4_ext_store_pblock(ex2, newblock);
ex2->ee_len = cpu_to_le16(allocated);
- ext4_ext_mark_uninitialized(ex2);
+ if (uninitialized)
+ ext4_ext_mark_uninitialized(ex2);
if (ex2 != ex)
goto insert;
/* Mark modified extent as dirty */
@@ -3018,7 +3050,8 @@ static int ext4_split_unwritten_extents(handle_t *handle,
ext_debug("out here\n");
goto out;
insert:
- err = ext4_ext_insert_extent(handle, inode, path, &newex, flags);
+ err = ext4_ext_insert_extent(handle, inode, path, &newex,
+ map_blocks_flags);
if (err == -ENOSPC && may_zeroout) {
err = ext4_ext_zeroout(inode, &orig_ex);
if (err)
@@ -3040,7 +3073,8 @@ fix_extent_len:
ex->ee_block = orig_ex.ee_block;
ex->ee_len = orig_ex.ee_len;
ext4_ext_store_pblock(ex, ext4_ext_pblock(&orig_ex));
- ext4_ext_mark_uninitialized(ex);
+ if (uninitialized)
+ ext4_ext_mark_uninitialized(ex);
ext4_ext_dirty(handle, inode, path + depth);
return err;
}
@@ -3175,8 +3209,9 @@ ext4_ext_handle_uninitialized_extents(handle_t *handle, struct inode *inode,
/* get_block() before submit the IO, split the extent */
if ((flags & EXT4_GET_BLOCKS_PRE_IO)) {
- ret = ext4_split_unwritten_extents(handle, inode, map,
- path, flags);
+ ret = ext4_ext_split_extents(handle, inode, map,
+ path, flags,
+ EXT4_SPLIT_EXTENTS_UNWRITTEN);
/*
* Flag the inode(non aio case) or end_io struct (aio case)
* that this IO needs to convertion to written when IO is
--
1.7.1
--
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