On Fri, Jul 31, 2009 at 11:56:55PM -0700, Mingming wrote:
> Hi,
>
> I want to throw out my first attempt to fix the DIO fallocate issue, to
> see if the approach makes sense. This is the approach I take will
>
> 1) DIO write to hole will not fall back to buffered IO. holes are
> marked as unwritten extents after block allocation.
> 2) New extents allocated at the end of file is also treated as unwritten
> extents
> 3) those unwritten extents, and fallocate extents, will be converted to
> written extents (and update disk isize if needed)when the IO is
> complete. The conversion is triggered using end_io call back function
> passing from ext4 fs to direct IO.
>
> 4) We need to tell direct IO do not force create =0 for write on holes.
> Does not want use blockdev_dio_own_locking(), instead,add another dio
> type which indicating DIO that fs still needs the lock handling at VFS
> layer, but wants to take care of the hole/unwritten stuff by fs itself.
>
> untested patch below...
>
> Signed-off-by: Mingming Cao <cmm@xxxxxxxxxx>
> ---
> fs/direct-io.c | 26 +++++++-
> fs/ext4/Makefile | 4 -
> fs/ext4/dio.c | 162 +++++++++++++++++++++++++++++++++++++++++++++++++++++
> fs/ext4/ext4.h | 22 ++++++-
> fs/ext4/extents.c | 66 +++++++++++++++++++++
> fs/ext4/inode.c | 83 ---------------------------
> fs/ext4/super.c | 11 +++
> include/linux/fs.h | 10 +++
> 8 files changed, 293 insertions(+), 91 deletions(-)
>
> Index: linux-2.6.31-rc4/fs/ext4/inode.c
> ===================================================================
> --- linux-2.6.31-rc4.orig/fs/ext4/inode.c 2009-07-31 12:57:53.000000000 -0700
> +++ linux-2.6.31-rc4/fs/ext4/inode.c 2009-07-31 14:48:27.000000000 -0700
> @@ -3279,89 +3279,6 @@ static int ext4_releasepage(struct page
> }
>
> /*
> - * If the O_DIRECT write will extend the file then add this inode to the
> - * orphan list. So recovery will truncate it back to the original size
> - * if the machine crashes during the write.
> - *
> - * If the O_DIRECT write is intantiating holes inside i_size and the machine
> - * crashes then stale disk data _may_ be exposed inside the file. But current
> - * VFS code falls back into buffered path in that case so we are safe.
> - */
> -static ssize_t ext4_direct_IO(int rw, struct kiocb *iocb,
> - const struct iovec *iov, loff_t offset,
> - unsigned long nr_segs)
> -{
> - struct file *file = iocb->ki_filp;
> - struct inode *inode = file->f_mapping->host;
> - struct ext4_inode_info *ei = EXT4_I(inode);
> - handle_t *handle;
> - ssize_t ret;
> - int orphan = 0;
> - size_t count = iov_length(iov, nr_segs);
> -
> - if (rw == WRITE) {
> - loff_t final_size = offset + count;
> -
> - if (final_size > inode->i_size) {
> - /* Credits for sb + inode write */
> - handle = ext4_journal_start(inode, 2);
> - if (IS_ERR(handle)) {
> - ret = PTR_ERR(handle);
> - goto out;
> - }
> - ret = ext4_orphan_add(handle, inode);
> - if (ret) {
> - ext4_journal_stop(handle);
> - goto out;
> - }
> - orphan = 1;
> - ei->i_disksize = inode->i_size;
> - ext4_journal_stop(handle);
> - }
> - }
> -
> - ret = blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov,
> - offset, nr_segs,
> - ext4_get_block, NULL);
> -
> - if (orphan) {
> - int err;
> -
> - /* Credits for sb + inode write */
> - handle = ext4_journal_start(inode, 2);
> - if (IS_ERR(handle)) {
> - /* This is really bad luck. We've written the data
> - * but cannot extend i_size. Bail out and pretend
> - * the write failed... */
> - ret = PTR_ERR(handle);
> - goto out;
> - }
> - if (inode->i_nlink)
> - ext4_orphan_del(handle, inode);
> - if (ret > 0) {
> - loff_t end = offset + ret;
> - if (end > inode->i_size) {
> - ei->i_disksize = end;
> - block_extend_i_size(inode, offset, ret);
> - /*
> - * We're going to return a positive `ret'
> - * here due to non-zero-length I/O, so there's
> - * no way of reporting error returns from
> - * ext4_mark_inode_dirty() to userspace. So
> - * ignore it.
> - */
> - ext4_mark_inode_dirty(handle, inode);
> - }
> - }
> - err = ext4_journal_stop(handle);
> - if (ret == 0)
> - ret = err;
> - }
> -out:
> - return ret;
> -}
> -
> -/*
> * Pages can be marked dirty completely asynchronously from ext4's journalling
> * activity. By filemap_sync_pte(), try_to_unmap_one(), etc. We cannot do
> * much here because ->set_page_dirty is called under VFS locks. The page is
> Index: linux-2.6.31-rc4/fs/ext4/ext4.h
> ===================================================================
> --- linux-2.6.31-rc4.orig/fs/ext4/ext4.h 2009-07-31 12:57:53.000000000 -0700
> +++ linux-2.6.31-rc4/fs/ext4/ext4.h 2009-07-31 23:31:26.000000000 -0700
> @@ -111,6 +111,15 @@ struct ext4_allocation_request {
> unsigned int flags;
> };
>
> +typedef struct ext4_io_end{
> + struct inode *inode; /* file being written to */
> + unsigned int type; /* unwritten or written */
> + int error; /* I/O error code */
> + ext4_lblk_t offset; /* offset in the file */
> + size_t size; /* size of the extent */
> + struct work_struct work; /* data work queue */
> +}ext4_io_end_t;
> +
> /*
> * Special inodes numbers
> */
> @@ -330,8 +339,8 @@ struct ext4_new_group_data {
> /* Call ext4_da_update_reserve_space() after successfully
> allocating the blocks */
> #define EXT4_GET_BLOCKS_UPDATE_RESERVE_SPACE 0x0008
> -
> -
> +#define EXT4_GET_BLOCKS_DIO 0x0010
> +#define EXT4_GET_BLOCKS_CONVERT_UNINIT 0x0020
> /*
> * ioctl commands
> */
> @@ -960,6 +969,9 @@ struct ext4_sb_info {
>
> unsigned int s_log_groups_per_flex;
> struct flex_groups *s_flex_groups;
> +
> + /* workqueue for dio unwritten */
> + struct workqueue_struct *dio_unwritten_wq;
> };
>
> static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
> @@ -1453,6 +1465,10 @@ extern __le16 ext4_group_desc_csum(struc
> struct ext4_group_desc *gdp);
> extern int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 group,
> struct ext4_group_desc *gdp);
> +/* dio.c */
> +extern ssize_t ext4_direct_IO(int rw, struct kiocb *iocb,
> + const struct iovec *iov, loff_t offset,
> + unsigned long nr_segs);
>
> static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
> {
> @@ -1650,6 +1666,8 @@ extern void ext4_ext_init(struct super_b
> extern void ext4_ext_release(struct super_block *);
> extern long ext4_fallocate(struct inode *inode, int mode, loff_t offset,
> loff_t len);
> +extern long ext4_convert_unwritten(struct inode *inode, loff_t offset,
> + loff_t len);
> extern int ext4_get_blocks(handle_t *handle, struct inode *inode,
> sector_t block, unsigned int max_blocks,
> struct buffer_head *bh, int flags);
> Index: linux-2.6.31-rc4/fs/ext4/dio.c
> ===================================================================
> --- /dev/null 1970-01-01 00:00:00.000000000 +0000
> +++ linux-2.6.31-rc4/fs/ext4/dio.c 2009-07-31 23:24:25.000000000 -0700
> @@ -0,0 +1,162 @@
> +/*
> + * linux/fs/ext4/dio.c
> + *
> + */
> +
> +#include <linux/fs.h>
> +#include <linux/jbd2.h>
> +#include <linux/buffer_head.h>
> +#include <linux/writeback.h>
> +#include <linux/bio.h>
> +#include <linux/workqueue.h>
> +
> +#include "ext4_jbd2.h"
> +
> +struct workqueue_struct *ext4_unwritten_queue;
> +
> +/* Maximum number of blocks we map for direct IO at once. */
> +#define DIO_MAX_BLOCKS 4096
> +int ext4_get_block_dio(struct inode *inode, sector_t iblock,
> + struct buffer_head *bh_result, int create)
> +{
> + handle_t *handle;
> + int ret = 0, started = 0;
> + unsigned max_blocks = bh_result->b_size >> inode->i_blkbits;
> + int dio_credits;
> + loff_t offset = (loff_t)iblock << inode->i_blkbits;
> + unsigned int flags = 0;
> +
> + if (create) {
> + if (max_blocks > DIO_MAX_BLOCKS)
> + max_blocks = DIO_MAX_BLOCKS;
> + dio_credits = ext4_chunk_trans_blocks(inode, max_blocks);
> + handle = ext4_journal_start(inode, dio_credits);
> + if (IS_ERR(handle)) {
> + ret = PTR_ERR(handle);
> + goto out;
> + }
> + started = 1;
> +
> + flags = EXT4_GET_BLOCKS_CREATE_UNINIT_EXT;
That would imply we are always creating uninit extent. You will have to make
sure we do the right thing with bh_flag of bh_result in this case. We have
ignored bh_flag update for EXT4_GET_BLOCKS_CREATE_UNINIT_EXT because that was
initially done only from the fallocate call path which didn't look at the flag
at all.
> + }
> +
> + ret = ext4_get_blocks(handle, inode, iblock, max_blocks, bh_result,
> + flags);
> + if (ret > 0) {
> + bh_result->b_size = (ret << inode->i_blkbits);
> + ret = 0;
> + }
> + if (started)
> + ext4_journal_stop(handle);
> +out:
> + return ret;
> +}
> +
> +#define DIO_UNWRITTEN 0x1
> +
> +/*
> + * IO write completion for unwritten extents.
> + *
> + * convert a buffer range from unwritten to written extents.
> + */
> +static void ext4_end_dio_unwritten(struct work_struct *work)
> +{
> + ext4_io_end_t *io = container_of(work, ext4_io_end_t, work);
> + struct inode *inode = io->inode;
> + loff_t offset = io->offset;
> + size_t size = io->size;
> +
> + ext4_convert_unwritten(inode, offset, size);
> +
> + kfree(io);
> +}
> +
> +ext4_io_end_t *ext4_init_io_end (struct inode *inode, unsigned int type)
> +{
> + ext4_io_end_t *io = NULL;
> +
> + io = kmalloc(sizeof(*io), GFP_NOFS);
> +
> + if (io) {
> + io->inode = inode;
> + io->type = type;
> + io->offset = 0;
> + io->size = 0;
> + io->error = 0;
> + INIT_WORK(&io->work, ext4_end_dio_unwritten);
> + }
> +
> + return io;
> +}
> +
> +static void ext4_end_io_dio(struct kiocb *iocb, loff_t offset,
> + ssize_t size, void *private)
> +{
> + ext4_io_end_t *io_end = iocb->private;
> + struct workqueue_struct *wq;
> + /*FIX ME call ext4 code to convert the extents, commit the log*/
> +
> + /* if not hole or unwritten extents, just simple return */
> + if (!io_endi || !size)
> + return;
> + io_end->offset = offset;
> + io_end->size = size;
> + wq = EXT4_SB(io_end->inode->i_sb)->dio_unwritten_wq;
> +
> + /* We need to convert unwritten extents to written */
> + queue_work(wq, &io_end->work);
> +
> + if (is_sync_kiocb(iocb))
> + flush_workqueue(wq);
> +
> + iocb->private = NULL;
> +}
> +/*
> + * If the O_DIRECT write will extend the file then add this inode to the
> + * orphan list. So recovery will truncate it back to the original size
> + * if the machine crashes during the write.
> + *
> + * If the O_DIRECT write is filling unintialized space inside i_size,
> + * convertion to initialized extent should happen after data written to disk
> + * to ensure we don't expose stale disk data after crash.
> + */
> +ssize_t ext4_direct_IO(int rw, struct kiocb *iocb,
> + const struct iovec *iov, loff_t offset,
> + unsigned long nr_segs)
> +{
> + struct file *file = iocb->ki_filp;
> + struct inode *inode = file->f_mapping->host;
> + struct ext4_inode_info *ei = EXT4_I(inode);
> + handle_t *handle;
> + ssize_t ret;
> + int orphan = 0;
> + size_t count = iov_length(iov, nr_segs);
> +
> + if (rw == WRITE) {
> + /*
> + * we treat blocks allocated for DIO as
> + * as unwritten extents, need to convert them
> + * to written extents when IO is complete.
> + *
> + * In the case of AIO DIO, since VFS dio code
> + * does not wait for io complete, here
> + * i_size update needs to be buddled at the
> + * time DIO IO is completed, not here
> + */
> + iocb->private = ext4_init_io_end(inode, DIO_UNWRITTEN);
> + if (!iocb->private)
> + return -ENOMEM;
> + }
> +
> + ret = blockdev_direct_IO_hole(rw, iocb, inode,
> + inode->i_sb->s_bdev, iov,
> + offset, nr_segs,
> + ext4_get_block_dio, ext4_end_io_dio);
> +
> + /* In the case of AIO DIO, VFS dio,
> + * does not wait for io complete, here
> + * i_size update needs to be buddled at the
> + * time DIO IO is completed, not here
> + */
> + return ret;
> +}
> Index: linux-2.6.31-rc4/fs/ext4/Makefile
> ===================================================================
> --- linux-2.6.31-rc4.orig/fs/ext4/Makefile 2009-07-31 14:51:38.000000000 -0700
> +++ linux-2.6.31-rc4/fs/ext4/Makefile 2009-07-31 15:07:54.000000000 -0700
> @@ -6,8 +6,8 @@ obj-$(CONFIG_EXT4_FS) += ext4.o
>
> ext4-y := balloc.o bitmap.o dir.o file.o fsync.o ialloc.o inode.o \
> ioctl.o namei.o super.o symlink.o hash.o resize.o extents.o \
> - ext4_jbd2.o migrate.o mballoc.o block_validity.o move_extent.o
> -
> + ext4_jbd2.o migrate.o mballoc.o block_validity.o \
> + move_extent.o dio.o
> ext4-$(CONFIG_EXT4_FS_XATTR) += xattr.o xattr_user.o xattr_trusted.o
> ext4-$(CONFIG_EXT4_FS_POSIX_ACL) += acl.o
> ext4-$(CONFIG_EXT4_FS_SECURITY) += xattr_security.o
> Index: linux-2.6.31-rc4/fs/ext4/super.c
> ===================================================================
> --- linux-2.6.31-rc4.orig/fs/ext4/super.c 2009-07-31 15:26:23.000000000 -0700
> +++ linux-2.6.31-rc4/fs/ext4/super.c 2009-07-31 15:57:52.000000000 -0700
> @@ -578,6 +578,9 @@ static void ext4_put_super(struct super_
> struct ext4_super_block *es = sbi->s_es;
> int i, err;
>
> + flush_workqueue(sbi->dio_unwritten_wq);
> + destroy_workqueue(sbi->dio_unwritten_wq);
> +
> lock_super(sb);
> lock_kernel();
> if (sb->s_dirt)
> @@ -2781,6 +2784,12 @@ no_journal:
> clear_opt(sbi->s_mount_opt, NOBH);
> }
> }
> + EXT4_SB(sb)->dio_unwritten_wq = create_workqueue("ext4-dio-unwritten");
> + if (!EXT4_SB(sb)->dio_unwritten_wq) {
> + printk(KERN_ERR "EXT4-fs: failed to create DIO workqueue\n");
> + goto failed_mount_wq;
> + }
> +
> /*
> * The jbd2_journal_load will have done any necessary log recovery,
> * so we can safely mount the rest of the filesystem now.
> @@ -2893,6 +2902,8 @@ cantfind_ext4:
>
> failed_mount4:
> ext4_msg(sb, KERN_ERR, "mount failed");
> + destroy_workqueue(EXT4_SB(sb)->dio_unwritten_wq);
> +failed_mount_wq:
> ext4_release_system_zone(sb);
> if (sbi->s_journal) {
> jbd2_journal_destroy(sbi->s_journal);
> Index: linux-2.6.31-rc4/fs/direct-io.c
> ===================================================================
> --- linux-2.6.31-rc4.orig/fs/direct-io.c 2009-07-31 17:12:30.000000000 -0700
> +++ linux-2.6.31-rc4/fs/direct-io.c 2009-07-31 17:25:17.000000000 -0700
> @@ -240,7 +240,7 @@ static int dio_complete(struct dio *dio,
> if (dio->end_io && dio->result)
> dio->end_io(dio->iocb, offset, transferred,
> dio->map_bh.b_private);
> - if (dio->lock_type == DIO_LOCKING)
> + if (dio->lock_type == DIO_LOCKING || dio->lock_type == DIO_LOCKING_HOLE)
> /* lockdep: non-owner release */
> up_read_non_owner(&dio->inode->i_alloc_sem);
>
> @@ -516,6 +516,17 @@ static int get_more_blocks(struct dio *d
> map_bh->b_size = fs_count << dio->inode->i_blkbits;
>
> create = dio->rw & WRITE;
> + /*
> + * If the dio lock type does not indicate the underlying
> + * fs could handle unwritten extents, pass create as 0 to
> + * just do a plain block look up. If it is a hole, DIO will
> + * falls back to buffered IO to prevent stale data out after
> + * crash before IO complete.
> + *
> + * if the dio lock type is DIO_LOCKING_HOLE
> + * then dio will preserve the create flag, and let the
> + * underlying filesystem to handle the hole issue.
> + */
> if (dio->lock_type == DIO_LOCKING) {
> if (dio->block_in_file < (i_size_read(dio->inode) >>
> dio->blkbits))
> @@ -1042,7 +1053,8 @@ direct_io_worker(int rw, struct kiocb *i
> * we can let i_mutex go now that its achieved its purpose
> * of protecting us from looking up uninitialized blocks.
> */
> - if ((rw == READ) && (dio->lock_type == DIO_LOCKING))
> + if ((rw == READ) && (dio->lock_type == DIO_LOCKING ||
> + dio->lock_type == DIO_LOCKING_HOLE))
> mutex_unlock(&dio->inode->i_mutex);
>
> /*
> @@ -1097,6 +1109,10 @@ direct_io_worker(int rw, struct kiocb *i
> * For reads, i_mutex is not held on entry, but it is taken and dropped before
> * returning.
> *
> + * DIO_LOCKING_HOLE (simple locking for regular files)
> + * Same as above, except that filesystem support unwritten extents thus
> + * allow DIO to write to holes, no need to fall back to buffered IO.
> + *
> * DIO_OWN_LOCKING (filesystem provides synchronisation and handling of
> * uninitialised data, allowing parallel direct readers and writers)
> * For writes we are called without i_mutex, return without it, never touch it.
> @@ -1190,7 +1206,8 @@ __blockdev_direct_IO(int rw, struct kioc
> }
> }
>
> - if (dio_lock_type == DIO_LOCKING)
> + if (dio_lock_type == DIO_LOCKING ||
> + dio_lock_type == DIO_LOCKING_HOLE)
> /* lockdep: not the owner will release it */
> down_read_non_owner(&inode->i_alloc_sem);
> }
> @@ -1220,7 +1237,8 @@ __blockdev_direct_IO(int rw, struct kioc
> vmtruncate(inode, isize);
> }
>
> - if (rw == READ && dio_lock_type == DIO_LOCKING)
> + if (rw == READ && (dio_lock_type == DIO_LOCKING ||
> + dio_lock_type == DIO_LOCKING_HOLE))
> release_i_mutex = 0;
>
> out:
> Index: linux-2.6.31-rc4/include/linux/fs.h
> ===================================================================
> --- linux-2.6.31-rc4.orig/include/linux/fs.h 2009-07-31 17:09:07.000000000 -0700
> +++ linux-2.6.31-rc4/include/linux/fs.h 2009-07-31 17:20:39.000000000 -0700
> @@ -2255,6 +2255,7 @@ enum {
> DIO_LOCKING = 1, /* need locking between buffered and direct access */
> DIO_NO_LOCKING, /* bdev; no locking at all between buffered/direct */
> DIO_OWN_LOCKING, /* filesystem locks buffered and direct internally */
> + DIO_LOCKING_HOLE /* need locking, but allow DIO write to holes */
> };
>
> static inline ssize_t blockdev_direct_IO(int rw, struct kiocb *iocb,
> @@ -2283,6 +2284,15 @@ static inline ssize_t blockdev_direct_IO
> return __blockdev_direct_IO(rw, iocb, inode, bdev, iov, offset,
> nr_segs, get_block, end_io, DIO_OWN_LOCKING);
> }
> +
> +static inline ssize_t blockdev_direct_IO_hole(int rw, struct kiocb *iocb,
> + struct inode *inode, struct block_device *bdev, const struct iovec *iov,
> + loff_t offset, unsigned long nr_segs, get_block_t get_block,
> + dio_iodone_t end_io)
> +{
> + return __blockdev_direct_IO(rw, iocb, inode, bdev, iov, offset,
> + nr_segs, get_block, end_io, DIO_LOCKING_HOLE);
> +}
> #endif
>
> extern const struct file_operations generic_ro_fops;
> Index: linux-2.6.31-rc4/fs/ext4/extents.c
> ===================================================================
> --- linux-2.6.31-rc4.orig/fs/ext4/extents.c 2009-07-31 22:45:58.000000000 -0700
> +++ linux-2.6.31-rc4/fs/ext4/extents.c 2009-07-31 23:37:20.000000000 -0700
> @@ -3170,6 +3170,72 @@ retry:
> return ret > 0 ? ret2 : ret;
> }
>
> +long ext4_convert_unwritten(struct inode *inode, loff_t offset, loff_t len)
> +{
> + handle_t *handle;
> + ext4_lblk_t block;
> + loff_t new_size;
> + unsigned int max_blocks;
> + int ret = 0;
> + int ret2 = 0;
> + struct buffer_head map_bh;
> + unsigned int credits, blkbits = inode->i_blkbits;
> +
> + if (!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL))
> + return -EOPNOTSUPP;
> +
> + block = offset >> blkbits;
> + /*
> + * We can't just convert len to max_blocks because
> + * If blocksize = 4096 offset = 3072 and len = 2048
> + */
> + max_blocks = (EXT4_BLOCK_ALIGN(len + offset, blkbits) >> blkbits)
> + - block;
> + /*
> + * credits to insert 1 extent into extent tree
> + */
> + credits = ext4_chunk_trans_blocks(inode, max_blocks);
> + while (ret >= 0 && ret < max_blocks) {
> + block = block + ret;
> + max_blocks = max_blocks - ret;
> + handle = ext4_journal_start(inode, credits);
> + if (IS_ERR(handle)) {
> + ret = PTR_ERR(handle);
> + break;
> + }
> + map_bh.b_state = 0;
> + ret = ext4_get_blocks(handle, inode, block,
> + max_blocks, &map_bh,
> + EXT4_GET_BLOCKS_CONVERT_UNINIT_EXT)
Where is EXT4_GET_BLOCKS_CONVERT_UNINIT_EXT defined ? Assuming it is
EXT4_GET_BLOCKS_CREATE, it implies we can endup doing block allocation
here. If we don't have enough space, we zero-out the full extent. Which
implies we would endup overwritting the already wrote contents.
;
> + if (ret <= 0) {
> + WARN_ON(ret <= 0);
> + printk(KERN_ERR "%s: ext4_ext_get_blocks "
> + "returned error inode#%lu, block=%u, "
> + "max_blocks=%u", __func__,
> + inode->i_ino, block, max_blocks);
> + ext4_mark_inode_dirty(handle, inode);
> + ret2 = ext4_journal_stop(handle);
> + break;
> + }
> +
> + if ((block + ret) >= (EXT4_BLOCK_ALIGN(offset + len,
> + blkbits) >> blkbits))
> + new_size = offset + len;
> + else
> + new_size = (block + ret) << blkbits;
> +
> + if (new_size > i_size_read(inode))
> + i_size_write(inode, new_size);
shouldn't i_size update always happen with inode->i_mutex held. I guess
we can't do a i_size update in end_io call back.
> + if (new_size > EXT4_I(inode)->i_disksize)
> + ext4_update_i_disksize(inode, new_size);
> +
> + ext4_mark_inode_dirty(handle, inode);
> + ret2 = ext4_journal_stop(handle);
> + if (ret2)
> + break;
> + }
> + return ret > 0 ? ret2 : ret;
> +}
> /*
> * Callback function called for each extent to gather FIEMAP information.
> */
>
>
Can you send it as a multi patch series. Having only ext4 specific changes
to look at will makes this review easier.
-aneesh
--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
