mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-26 02:39:48 +00:00
![Christoph Hellwig](/assets/img/avatar_default.png)
Now that we use the VFS i_size field throughout XFS there is no need for the i_new_size field any more given that the VFS i_size field gets updated in ->write_end before unlocking the page, and thus is always uptodate when writeback could see a page. Removing i_new_size also has the advantage that we will never have to trim back di_size during a failed buffered write, given that it never gets updated past i_size. Note that currently the generic direct I/O code only updates i_size after calling our end_io handler, which requires a small workaround to make sure di_size actually makes it to disk. I hope to fix this properly in the generic code. A downside is that we lose the support for parallel non-overlapping O_DIRECT appending writes that recently was added. I don't think keeping the complex and fragile i_new_size infrastructure for this is a good tradeoff - if we really care about parallel appending writers we should investigate turning the iolock into a range lock, which would also allow for parallel non-overlapping buffered writers. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Ben Myers <bpm@sgi.com>
1468 lines
35 KiB
C
1468 lines
35 KiB
C
/*
|
|
* Copyright (c) 2000-2005 Silicon Graphics, Inc.
|
|
* All Rights Reserved.
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License as
|
|
* published by the Free Software Foundation.
|
|
*
|
|
* This program is distributed in the hope that it would be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write the Free Software Foundation,
|
|
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
|
|
*/
|
|
#include "xfs.h"
|
|
#include "xfs_bit.h"
|
|
#include "xfs_log.h"
|
|
#include "xfs_inum.h"
|
|
#include "xfs_sb.h"
|
|
#include "xfs_ag.h"
|
|
#include "xfs_trans.h"
|
|
#include "xfs_mount.h"
|
|
#include "xfs_bmap_btree.h"
|
|
#include "xfs_dinode.h"
|
|
#include "xfs_inode.h"
|
|
#include "xfs_alloc.h"
|
|
#include "xfs_error.h"
|
|
#include "xfs_rw.h"
|
|
#include "xfs_iomap.h"
|
|
#include "xfs_vnodeops.h"
|
|
#include "xfs_trace.h"
|
|
#include "xfs_bmap.h"
|
|
#include <linux/gfp.h>
|
|
#include <linux/mpage.h>
|
|
#include <linux/pagevec.h>
|
|
#include <linux/writeback.h>
|
|
|
|
void
|
|
xfs_count_page_state(
|
|
struct page *page,
|
|
int *delalloc,
|
|
int *unwritten)
|
|
{
|
|
struct buffer_head *bh, *head;
|
|
|
|
*delalloc = *unwritten = 0;
|
|
|
|
bh = head = page_buffers(page);
|
|
do {
|
|
if (buffer_unwritten(bh))
|
|
(*unwritten) = 1;
|
|
else if (buffer_delay(bh))
|
|
(*delalloc) = 1;
|
|
} while ((bh = bh->b_this_page) != head);
|
|
}
|
|
|
|
STATIC struct block_device *
|
|
xfs_find_bdev_for_inode(
|
|
struct inode *inode)
|
|
{
|
|
struct xfs_inode *ip = XFS_I(inode);
|
|
struct xfs_mount *mp = ip->i_mount;
|
|
|
|
if (XFS_IS_REALTIME_INODE(ip))
|
|
return mp->m_rtdev_targp->bt_bdev;
|
|
else
|
|
return mp->m_ddev_targp->bt_bdev;
|
|
}
|
|
|
|
/*
|
|
* We're now finished for good with this ioend structure.
|
|
* Update the page state via the associated buffer_heads,
|
|
* release holds on the inode and bio, and finally free
|
|
* up memory. Do not use the ioend after this.
|
|
*/
|
|
STATIC void
|
|
xfs_destroy_ioend(
|
|
xfs_ioend_t *ioend)
|
|
{
|
|
struct buffer_head *bh, *next;
|
|
|
|
for (bh = ioend->io_buffer_head; bh; bh = next) {
|
|
next = bh->b_private;
|
|
bh->b_end_io(bh, !ioend->io_error);
|
|
}
|
|
|
|
if (ioend->io_iocb) {
|
|
if (ioend->io_isasync) {
|
|
aio_complete(ioend->io_iocb, ioend->io_error ?
|
|
ioend->io_error : ioend->io_result, 0);
|
|
}
|
|
inode_dio_done(ioend->io_inode);
|
|
}
|
|
|
|
mempool_free(ioend, xfs_ioend_pool);
|
|
}
|
|
|
|
/*
|
|
* If the end of the current ioend is beyond the current EOF,
|
|
* return the new EOF value, otherwise zero.
|
|
*/
|
|
STATIC xfs_fsize_t
|
|
xfs_ioend_new_eof(
|
|
xfs_ioend_t *ioend)
|
|
{
|
|
xfs_inode_t *ip = XFS_I(ioend->io_inode);
|
|
xfs_fsize_t isize;
|
|
xfs_fsize_t bsize;
|
|
|
|
bsize = ioend->io_offset + ioend->io_size;
|
|
isize = MIN(i_size_read(VFS_I(ip)), bsize);
|
|
return isize > ip->i_d.di_size ? isize : 0;
|
|
}
|
|
|
|
/*
|
|
* Fast and loose check if this write could update the on-disk inode size.
|
|
*/
|
|
static inline bool xfs_ioend_is_append(struct xfs_ioend *ioend)
|
|
{
|
|
return ioend->io_offset + ioend->io_size >
|
|
XFS_I(ioend->io_inode)->i_d.di_size;
|
|
}
|
|
|
|
/*
|
|
* Update on-disk file size now that data has been written to disk.
|
|
*
|
|
* This function does not block as blocking on the inode lock in IO completion
|
|
* can lead to IO completion order dependency deadlocks.. If it can't get the
|
|
* inode ilock it will return EAGAIN. Callers must handle this.
|
|
*/
|
|
STATIC int
|
|
xfs_setfilesize(
|
|
xfs_ioend_t *ioend)
|
|
{
|
|
xfs_inode_t *ip = XFS_I(ioend->io_inode);
|
|
xfs_fsize_t isize;
|
|
|
|
if (!xfs_ilock_nowait(ip, XFS_ILOCK_EXCL))
|
|
return EAGAIN;
|
|
|
|
isize = xfs_ioend_new_eof(ioend);
|
|
if (isize) {
|
|
trace_xfs_setfilesize(ip, ioend->io_offset, ioend->io_size);
|
|
ip->i_d.di_size = isize;
|
|
xfs_mark_inode_dirty(ip);
|
|
}
|
|
|
|
xfs_iunlock(ip, XFS_ILOCK_EXCL);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Schedule IO completion handling on the final put of an ioend.
|
|
*
|
|
* If there is no work to do we might as well call it a day and free the
|
|
* ioend right now.
|
|
*/
|
|
STATIC void
|
|
xfs_finish_ioend(
|
|
struct xfs_ioend *ioend)
|
|
{
|
|
if (atomic_dec_and_test(&ioend->io_remaining)) {
|
|
if (ioend->io_type == IO_UNWRITTEN)
|
|
queue_work(xfsconvertd_workqueue, &ioend->io_work);
|
|
else if (xfs_ioend_is_append(ioend))
|
|
queue_work(xfsdatad_workqueue, &ioend->io_work);
|
|
else
|
|
xfs_destroy_ioend(ioend);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* IO write completion.
|
|
*/
|
|
STATIC void
|
|
xfs_end_io(
|
|
struct work_struct *work)
|
|
{
|
|
xfs_ioend_t *ioend = container_of(work, xfs_ioend_t, io_work);
|
|
struct xfs_inode *ip = XFS_I(ioend->io_inode);
|
|
int error = 0;
|
|
|
|
if (XFS_FORCED_SHUTDOWN(ip->i_mount)) {
|
|
ioend->io_error = -EIO;
|
|
goto done;
|
|
}
|
|
if (ioend->io_error)
|
|
goto done;
|
|
|
|
/*
|
|
* For unwritten extents we need to issue transactions to convert a
|
|
* range to normal written extens after the data I/O has finished.
|
|
*/
|
|
if (ioend->io_type == IO_UNWRITTEN) {
|
|
error = xfs_iomap_write_unwritten(ip, ioend->io_offset,
|
|
ioend->io_size);
|
|
if (error) {
|
|
ioend->io_error = -error;
|
|
goto done;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* We might have to update the on-disk file size after extending
|
|
* writes.
|
|
*/
|
|
error = xfs_setfilesize(ioend);
|
|
ASSERT(!error || error == EAGAIN);
|
|
|
|
done:
|
|
/*
|
|
* If we didn't complete processing of the ioend, requeue it to the
|
|
* tail of the workqueue for another attempt later. Otherwise destroy
|
|
* it.
|
|
*/
|
|
if (error == EAGAIN) {
|
|
atomic_inc(&ioend->io_remaining);
|
|
xfs_finish_ioend(ioend);
|
|
/* ensure we don't spin on blocked ioends */
|
|
delay(1);
|
|
} else {
|
|
xfs_destroy_ioend(ioend);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Call IO completion handling in caller context on the final put of an ioend.
|
|
*/
|
|
STATIC void
|
|
xfs_finish_ioend_sync(
|
|
struct xfs_ioend *ioend)
|
|
{
|
|
if (atomic_dec_and_test(&ioend->io_remaining))
|
|
xfs_end_io(&ioend->io_work);
|
|
}
|
|
|
|
/*
|
|
* Allocate and initialise an IO completion structure.
|
|
* We need to track unwritten extent write completion here initially.
|
|
* We'll need to extend this for updating the ondisk inode size later
|
|
* (vs. incore size).
|
|
*/
|
|
STATIC xfs_ioend_t *
|
|
xfs_alloc_ioend(
|
|
struct inode *inode,
|
|
unsigned int type)
|
|
{
|
|
xfs_ioend_t *ioend;
|
|
|
|
ioend = mempool_alloc(xfs_ioend_pool, GFP_NOFS);
|
|
|
|
/*
|
|
* Set the count to 1 initially, which will prevent an I/O
|
|
* completion callback from happening before we have started
|
|
* all the I/O from calling the completion routine too early.
|
|
*/
|
|
atomic_set(&ioend->io_remaining, 1);
|
|
ioend->io_isasync = 0;
|
|
ioend->io_error = 0;
|
|
ioend->io_list = NULL;
|
|
ioend->io_type = type;
|
|
ioend->io_inode = inode;
|
|
ioend->io_buffer_head = NULL;
|
|
ioend->io_buffer_tail = NULL;
|
|
ioend->io_offset = 0;
|
|
ioend->io_size = 0;
|
|
ioend->io_iocb = NULL;
|
|
ioend->io_result = 0;
|
|
|
|
INIT_WORK(&ioend->io_work, xfs_end_io);
|
|
return ioend;
|
|
}
|
|
|
|
STATIC int
|
|
xfs_map_blocks(
|
|
struct inode *inode,
|
|
loff_t offset,
|
|
struct xfs_bmbt_irec *imap,
|
|
int type,
|
|
int nonblocking)
|
|
{
|
|
struct xfs_inode *ip = XFS_I(inode);
|
|
struct xfs_mount *mp = ip->i_mount;
|
|
ssize_t count = 1 << inode->i_blkbits;
|
|
xfs_fileoff_t offset_fsb, end_fsb;
|
|
int error = 0;
|
|
int bmapi_flags = XFS_BMAPI_ENTIRE;
|
|
int nimaps = 1;
|
|
|
|
if (XFS_FORCED_SHUTDOWN(mp))
|
|
return -XFS_ERROR(EIO);
|
|
|
|
if (type == IO_UNWRITTEN)
|
|
bmapi_flags |= XFS_BMAPI_IGSTATE;
|
|
|
|
if (!xfs_ilock_nowait(ip, XFS_ILOCK_SHARED)) {
|
|
if (nonblocking)
|
|
return -XFS_ERROR(EAGAIN);
|
|
xfs_ilock(ip, XFS_ILOCK_SHARED);
|
|
}
|
|
|
|
ASSERT(ip->i_d.di_format != XFS_DINODE_FMT_BTREE ||
|
|
(ip->i_df.if_flags & XFS_IFEXTENTS));
|
|
ASSERT(offset <= mp->m_maxioffset);
|
|
|
|
if (offset + count > mp->m_maxioffset)
|
|
count = mp->m_maxioffset - offset;
|
|
end_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)offset + count);
|
|
offset_fsb = XFS_B_TO_FSBT(mp, offset);
|
|
error = xfs_bmapi_read(ip, offset_fsb, end_fsb - offset_fsb,
|
|
imap, &nimaps, bmapi_flags);
|
|
xfs_iunlock(ip, XFS_ILOCK_SHARED);
|
|
|
|
if (error)
|
|
return -XFS_ERROR(error);
|
|
|
|
if (type == IO_DELALLOC &&
|
|
(!nimaps || isnullstartblock(imap->br_startblock))) {
|
|
error = xfs_iomap_write_allocate(ip, offset, count, imap);
|
|
if (!error)
|
|
trace_xfs_map_blocks_alloc(ip, offset, count, type, imap);
|
|
return -XFS_ERROR(error);
|
|
}
|
|
|
|
#ifdef DEBUG
|
|
if (type == IO_UNWRITTEN) {
|
|
ASSERT(nimaps);
|
|
ASSERT(imap->br_startblock != HOLESTARTBLOCK);
|
|
ASSERT(imap->br_startblock != DELAYSTARTBLOCK);
|
|
}
|
|
#endif
|
|
if (nimaps)
|
|
trace_xfs_map_blocks_found(ip, offset, count, type, imap);
|
|
return 0;
|
|
}
|
|
|
|
STATIC int
|
|
xfs_imap_valid(
|
|
struct inode *inode,
|
|
struct xfs_bmbt_irec *imap,
|
|
xfs_off_t offset)
|
|
{
|
|
offset >>= inode->i_blkbits;
|
|
|
|
return offset >= imap->br_startoff &&
|
|
offset < imap->br_startoff + imap->br_blockcount;
|
|
}
|
|
|
|
/*
|
|
* BIO completion handler for buffered IO.
|
|
*/
|
|
STATIC void
|
|
xfs_end_bio(
|
|
struct bio *bio,
|
|
int error)
|
|
{
|
|
xfs_ioend_t *ioend = bio->bi_private;
|
|
|
|
ASSERT(atomic_read(&bio->bi_cnt) >= 1);
|
|
ioend->io_error = test_bit(BIO_UPTODATE, &bio->bi_flags) ? 0 : error;
|
|
|
|
/* Toss bio and pass work off to an xfsdatad thread */
|
|
bio->bi_private = NULL;
|
|
bio->bi_end_io = NULL;
|
|
bio_put(bio);
|
|
|
|
xfs_finish_ioend(ioend);
|
|
}
|
|
|
|
STATIC void
|
|
xfs_submit_ioend_bio(
|
|
struct writeback_control *wbc,
|
|
xfs_ioend_t *ioend,
|
|
struct bio *bio)
|
|
{
|
|
atomic_inc(&ioend->io_remaining);
|
|
bio->bi_private = ioend;
|
|
bio->bi_end_io = xfs_end_bio;
|
|
|
|
/*
|
|
* If the I/O is beyond EOF we mark the inode dirty immediately
|
|
* but don't update the inode size until I/O completion.
|
|
*/
|
|
if (xfs_ioend_new_eof(ioend))
|
|
xfs_mark_inode_dirty(XFS_I(ioend->io_inode));
|
|
|
|
submit_bio(wbc->sync_mode == WB_SYNC_ALL ? WRITE_SYNC : WRITE, bio);
|
|
}
|
|
|
|
STATIC struct bio *
|
|
xfs_alloc_ioend_bio(
|
|
struct buffer_head *bh)
|
|
{
|
|
int nvecs = bio_get_nr_vecs(bh->b_bdev);
|
|
struct bio *bio = bio_alloc(GFP_NOIO, nvecs);
|
|
|
|
ASSERT(bio->bi_private == NULL);
|
|
bio->bi_sector = bh->b_blocknr * (bh->b_size >> 9);
|
|
bio->bi_bdev = bh->b_bdev;
|
|
return bio;
|
|
}
|
|
|
|
STATIC void
|
|
xfs_start_buffer_writeback(
|
|
struct buffer_head *bh)
|
|
{
|
|
ASSERT(buffer_mapped(bh));
|
|
ASSERT(buffer_locked(bh));
|
|
ASSERT(!buffer_delay(bh));
|
|
ASSERT(!buffer_unwritten(bh));
|
|
|
|
mark_buffer_async_write(bh);
|
|
set_buffer_uptodate(bh);
|
|
clear_buffer_dirty(bh);
|
|
}
|
|
|
|
STATIC void
|
|
xfs_start_page_writeback(
|
|
struct page *page,
|
|
int clear_dirty,
|
|
int buffers)
|
|
{
|
|
ASSERT(PageLocked(page));
|
|
ASSERT(!PageWriteback(page));
|
|
if (clear_dirty)
|
|
clear_page_dirty_for_io(page);
|
|
set_page_writeback(page);
|
|
unlock_page(page);
|
|
/* If no buffers on the page are to be written, finish it here */
|
|
if (!buffers)
|
|
end_page_writeback(page);
|
|
}
|
|
|
|
static inline int bio_add_buffer(struct bio *bio, struct buffer_head *bh)
|
|
{
|
|
return bio_add_page(bio, bh->b_page, bh->b_size, bh_offset(bh));
|
|
}
|
|
|
|
/*
|
|
* Submit all of the bios for all of the ioends we have saved up, covering the
|
|
* initial writepage page and also any probed pages.
|
|
*
|
|
* Because we may have multiple ioends spanning a page, we need to start
|
|
* writeback on all the buffers before we submit them for I/O. If we mark the
|
|
* buffers as we got, then we can end up with a page that only has buffers
|
|
* marked async write and I/O complete on can occur before we mark the other
|
|
* buffers async write.
|
|
*
|
|
* The end result of this is that we trip a bug in end_page_writeback() because
|
|
* we call it twice for the one page as the code in end_buffer_async_write()
|
|
* assumes that all buffers on the page are started at the same time.
|
|
*
|
|
* The fix is two passes across the ioend list - one to start writeback on the
|
|
* buffer_heads, and then submit them for I/O on the second pass.
|
|
*/
|
|
STATIC void
|
|
xfs_submit_ioend(
|
|
struct writeback_control *wbc,
|
|
xfs_ioend_t *ioend)
|
|
{
|
|
xfs_ioend_t *head = ioend;
|
|
xfs_ioend_t *next;
|
|
struct buffer_head *bh;
|
|
struct bio *bio;
|
|
sector_t lastblock = 0;
|
|
|
|
/* Pass 1 - start writeback */
|
|
do {
|
|
next = ioend->io_list;
|
|
for (bh = ioend->io_buffer_head; bh; bh = bh->b_private)
|
|
xfs_start_buffer_writeback(bh);
|
|
} while ((ioend = next) != NULL);
|
|
|
|
/* Pass 2 - submit I/O */
|
|
ioend = head;
|
|
do {
|
|
next = ioend->io_list;
|
|
bio = NULL;
|
|
|
|
for (bh = ioend->io_buffer_head; bh; bh = bh->b_private) {
|
|
|
|
if (!bio) {
|
|
retry:
|
|
bio = xfs_alloc_ioend_bio(bh);
|
|
} else if (bh->b_blocknr != lastblock + 1) {
|
|
xfs_submit_ioend_bio(wbc, ioend, bio);
|
|
goto retry;
|
|
}
|
|
|
|
if (bio_add_buffer(bio, bh) != bh->b_size) {
|
|
xfs_submit_ioend_bio(wbc, ioend, bio);
|
|
goto retry;
|
|
}
|
|
|
|
lastblock = bh->b_blocknr;
|
|
}
|
|
if (bio)
|
|
xfs_submit_ioend_bio(wbc, ioend, bio);
|
|
xfs_finish_ioend(ioend);
|
|
} while ((ioend = next) != NULL);
|
|
}
|
|
|
|
/*
|
|
* Cancel submission of all buffer_heads so far in this endio.
|
|
* Toss the endio too. Only ever called for the initial page
|
|
* in a writepage request, so only ever one page.
|
|
*/
|
|
STATIC void
|
|
xfs_cancel_ioend(
|
|
xfs_ioend_t *ioend)
|
|
{
|
|
xfs_ioend_t *next;
|
|
struct buffer_head *bh, *next_bh;
|
|
|
|
do {
|
|
next = ioend->io_list;
|
|
bh = ioend->io_buffer_head;
|
|
do {
|
|
next_bh = bh->b_private;
|
|
clear_buffer_async_write(bh);
|
|
unlock_buffer(bh);
|
|
} while ((bh = next_bh) != NULL);
|
|
|
|
mempool_free(ioend, xfs_ioend_pool);
|
|
} while ((ioend = next) != NULL);
|
|
}
|
|
|
|
/*
|
|
* Test to see if we've been building up a completion structure for
|
|
* earlier buffers -- if so, we try to append to this ioend if we
|
|
* can, otherwise we finish off any current ioend and start another.
|
|
* Return true if we've finished the given ioend.
|
|
*/
|
|
STATIC void
|
|
xfs_add_to_ioend(
|
|
struct inode *inode,
|
|
struct buffer_head *bh,
|
|
xfs_off_t offset,
|
|
unsigned int type,
|
|
xfs_ioend_t **result,
|
|
int need_ioend)
|
|
{
|
|
xfs_ioend_t *ioend = *result;
|
|
|
|
if (!ioend || need_ioend || type != ioend->io_type) {
|
|
xfs_ioend_t *previous = *result;
|
|
|
|
ioend = xfs_alloc_ioend(inode, type);
|
|
ioend->io_offset = offset;
|
|
ioend->io_buffer_head = bh;
|
|
ioend->io_buffer_tail = bh;
|
|
if (previous)
|
|
previous->io_list = ioend;
|
|
*result = ioend;
|
|
} else {
|
|
ioend->io_buffer_tail->b_private = bh;
|
|
ioend->io_buffer_tail = bh;
|
|
}
|
|
|
|
bh->b_private = NULL;
|
|
ioend->io_size += bh->b_size;
|
|
}
|
|
|
|
STATIC void
|
|
xfs_map_buffer(
|
|
struct inode *inode,
|
|
struct buffer_head *bh,
|
|
struct xfs_bmbt_irec *imap,
|
|
xfs_off_t offset)
|
|
{
|
|
sector_t bn;
|
|
struct xfs_mount *m = XFS_I(inode)->i_mount;
|
|
xfs_off_t iomap_offset = XFS_FSB_TO_B(m, imap->br_startoff);
|
|
xfs_daddr_t iomap_bn = xfs_fsb_to_db(XFS_I(inode), imap->br_startblock);
|
|
|
|
ASSERT(imap->br_startblock != HOLESTARTBLOCK);
|
|
ASSERT(imap->br_startblock != DELAYSTARTBLOCK);
|
|
|
|
bn = (iomap_bn >> (inode->i_blkbits - BBSHIFT)) +
|
|
((offset - iomap_offset) >> inode->i_blkbits);
|
|
|
|
ASSERT(bn || XFS_IS_REALTIME_INODE(XFS_I(inode)));
|
|
|
|
bh->b_blocknr = bn;
|
|
set_buffer_mapped(bh);
|
|
}
|
|
|
|
STATIC void
|
|
xfs_map_at_offset(
|
|
struct inode *inode,
|
|
struct buffer_head *bh,
|
|
struct xfs_bmbt_irec *imap,
|
|
xfs_off_t offset)
|
|
{
|
|
ASSERT(imap->br_startblock != HOLESTARTBLOCK);
|
|
ASSERT(imap->br_startblock != DELAYSTARTBLOCK);
|
|
|
|
xfs_map_buffer(inode, bh, imap, offset);
|
|
set_buffer_mapped(bh);
|
|
clear_buffer_delay(bh);
|
|
clear_buffer_unwritten(bh);
|
|
}
|
|
|
|
/*
|
|
* Test if a given page is suitable for writing as part of an unwritten
|
|
* or delayed allocate extent.
|
|
*/
|
|
STATIC int
|
|
xfs_is_delayed_page(
|
|
struct page *page,
|
|
unsigned int type)
|
|
{
|
|
if (PageWriteback(page))
|
|
return 0;
|
|
|
|
if (page->mapping && page_has_buffers(page)) {
|
|
struct buffer_head *bh, *head;
|
|
int acceptable = 0;
|
|
|
|
bh = head = page_buffers(page);
|
|
do {
|
|
if (buffer_unwritten(bh))
|
|
acceptable = (type == IO_UNWRITTEN);
|
|
else if (buffer_delay(bh))
|
|
acceptable = (type == IO_DELALLOC);
|
|
else if (buffer_dirty(bh) && buffer_mapped(bh))
|
|
acceptable = (type == IO_OVERWRITE);
|
|
else
|
|
break;
|
|
} while ((bh = bh->b_this_page) != head);
|
|
|
|
if (acceptable)
|
|
return 1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Allocate & map buffers for page given the extent map. Write it out.
|
|
* except for the original page of a writepage, this is called on
|
|
* delalloc/unwritten pages only, for the original page it is possible
|
|
* that the page has no mapping at all.
|
|
*/
|
|
STATIC int
|
|
xfs_convert_page(
|
|
struct inode *inode,
|
|
struct page *page,
|
|
loff_t tindex,
|
|
struct xfs_bmbt_irec *imap,
|
|
xfs_ioend_t **ioendp,
|
|
struct writeback_control *wbc)
|
|
{
|
|
struct buffer_head *bh, *head;
|
|
xfs_off_t end_offset;
|
|
unsigned long p_offset;
|
|
unsigned int type;
|
|
int len, page_dirty;
|
|
int count = 0, done = 0, uptodate = 1;
|
|
xfs_off_t offset = page_offset(page);
|
|
|
|
if (page->index != tindex)
|
|
goto fail;
|
|
if (!trylock_page(page))
|
|
goto fail;
|
|
if (PageWriteback(page))
|
|
goto fail_unlock_page;
|
|
if (page->mapping != inode->i_mapping)
|
|
goto fail_unlock_page;
|
|
if (!xfs_is_delayed_page(page, (*ioendp)->io_type))
|
|
goto fail_unlock_page;
|
|
|
|
/*
|
|
* page_dirty is initially a count of buffers on the page before
|
|
* EOF and is decremented as we move each into a cleanable state.
|
|
*
|
|
* Derivation:
|
|
*
|
|
* End offset is the highest offset that this page should represent.
|
|
* If we are on the last page, (end_offset & (PAGE_CACHE_SIZE - 1))
|
|
* will evaluate non-zero and be less than PAGE_CACHE_SIZE and
|
|
* hence give us the correct page_dirty count. On any other page,
|
|
* it will be zero and in that case we need page_dirty to be the
|
|
* count of buffers on the page.
|
|
*/
|
|
end_offset = min_t(unsigned long long,
|
|
(xfs_off_t)(page->index + 1) << PAGE_CACHE_SHIFT,
|
|
i_size_read(inode));
|
|
|
|
len = 1 << inode->i_blkbits;
|
|
p_offset = min_t(unsigned long, end_offset & (PAGE_CACHE_SIZE - 1),
|
|
PAGE_CACHE_SIZE);
|
|
p_offset = p_offset ? roundup(p_offset, len) : PAGE_CACHE_SIZE;
|
|
page_dirty = p_offset / len;
|
|
|
|
bh = head = page_buffers(page);
|
|
do {
|
|
if (offset >= end_offset)
|
|
break;
|
|
if (!buffer_uptodate(bh))
|
|
uptodate = 0;
|
|
if (!(PageUptodate(page) || buffer_uptodate(bh))) {
|
|
done = 1;
|
|
continue;
|
|
}
|
|
|
|
if (buffer_unwritten(bh) || buffer_delay(bh) ||
|
|
buffer_mapped(bh)) {
|
|
if (buffer_unwritten(bh))
|
|
type = IO_UNWRITTEN;
|
|
else if (buffer_delay(bh))
|
|
type = IO_DELALLOC;
|
|
else
|
|
type = IO_OVERWRITE;
|
|
|
|
if (!xfs_imap_valid(inode, imap, offset)) {
|
|
done = 1;
|
|
continue;
|
|
}
|
|
|
|
lock_buffer(bh);
|
|
if (type != IO_OVERWRITE)
|
|
xfs_map_at_offset(inode, bh, imap, offset);
|
|
xfs_add_to_ioend(inode, bh, offset, type,
|
|
ioendp, done);
|
|
|
|
page_dirty--;
|
|
count++;
|
|
} else {
|
|
done = 1;
|
|
}
|
|
} while (offset += len, (bh = bh->b_this_page) != head);
|
|
|
|
if (uptodate && bh == head)
|
|
SetPageUptodate(page);
|
|
|
|
if (count) {
|
|
if (--wbc->nr_to_write <= 0 &&
|
|
wbc->sync_mode == WB_SYNC_NONE)
|
|
done = 1;
|
|
}
|
|
xfs_start_page_writeback(page, !page_dirty, count);
|
|
|
|
return done;
|
|
fail_unlock_page:
|
|
unlock_page(page);
|
|
fail:
|
|
return 1;
|
|
}
|
|
|
|
/*
|
|
* Convert & write out a cluster of pages in the same extent as defined
|
|
* by mp and following the start page.
|
|
*/
|
|
STATIC void
|
|
xfs_cluster_write(
|
|
struct inode *inode,
|
|
pgoff_t tindex,
|
|
struct xfs_bmbt_irec *imap,
|
|
xfs_ioend_t **ioendp,
|
|
struct writeback_control *wbc,
|
|
pgoff_t tlast)
|
|
{
|
|
struct pagevec pvec;
|
|
int done = 0, i;
|
|
|
|
pagevec_init(&pvec, 0);
|
|
while (!done && tindex <= tlast) {
|
|
unsigned len = min_t(pgoff_t, PAGEVEC_SIZE, tlast - tindex + 1);
|
|
|
|
if (!pagevec_lookup(&pvec, inode->i_mapping, tindex, len))
|
|
break;
|
|
|
|
for (i = 0; i < pagevec_count(&pvec); i++) {
|
|
done = xfs_convert_page(inode, pvec.pages[i], tindex++,
|
|
imap, ioendp, wbc);
|
|
if (done)
|
|
break;
|
|
}
|
|
|
|
pagevec_release(&pvec);
|
|
cond_resched();
|
|
}
|
|
}
|
|
|
|
STATIC void
|
|
xfs_vm_invalidatepage(
|
|
struct page *page,
|
|
unsigned long offset)
|
|
{
|
|
trace_xfs_invalidatepage(page->mapping->host, page, offset);
|
|
block_invalidatepage(page, offset);
|
|
}
|
|
|
|
/*
|
|
* If the page has delalloc buffers on it, we need to punch them out before we
|
|
* invalidate the page. If we don't, we leave a stale delalloc mapping on the
|
|
* inode that can trip a BUG() in xfs_get_blocks() later on if a direct IO read
|
|
* is done on that same region - the delalloc extent is returned when none is
|
|
* supposed to be there.
|
|
*
|
|
* We prevent this by truncating away the delalloc regions on the page before
|
|
* invalidating it. Because they are delalloc, we can do this without needing a
|
|
* transaction. Indeed - if we get ENOSPC errors, we have to be able to do this
|
|
* truncation without a transaction as there is no space left for block
|
|
* reservation (typically why we see a ENOSPC in writeback).
|
|
*
|
|
* This is not a performance critical path, so for now just do the punching a
|
|
* buffer head at a time.
|
|
*/
|
|
STATIC void
|
|
xfs_aops_discard_page(
|
|
struct page *page)
|
|
{
|
|
struct inode *inode = page->mapping->host;
|
|
struct xfs_inode *ip = XFS_I(inode);
|
|
struct buffer_head *bh, *head;
|
|
loff_t offset = page_offset(page);
|
|
|
|
if (!xfs_is_delayed_page(page, IO_DELALLOC))
|
|
goto out_invalidate;
|
|
|
|
if (XFS_FORCED_SHUTDOWN(ip->i_mount))
|
|
goto out_invalidate;
|
|
|
|
xfs_alert(ip->i_mount,
|
|
"page discard on page %p, inode 0x%llx, offset %llu.",
|
|
page, ip->i_ino, offset);
|
|
|
|
xfs_ilock(ip, XFS_ILOCK_EXCL);
|
|
bh = head = page_buffers(page);
|
|
do {
|
|
int error;
|
|
xfs_fileoff_t start_fsb;
|
|
|
|
if (!buffer_delay(bh))
|
|
goto next_buffer;
|
|
|
|
start_fsb = XFS_B_TO_FSBT(ip->i_mount, offset);
|
|
error = xfs_bmap_punch_delalloc_range(ip, start_fsb, 1);
|
|
if (error) {
|
|
/* something screwed, just bail */
|
|
if (!XFS_FORCED_SHUTDOWN(ip->i_mount)) {
|
|
xfs_alert(ip->i_mount,
|
|
"page discard unable to remove delalloc mapping.");
|
|
}
|
|
break;
|
|
}
|
|
next_buffer:
|
|
offset += 1 << inode->i_blkbits;
|
|
|
|
} while ((bh = bh->b_this_page) != head);
|
|
|
|
xfs_iunlock(ip, XFS_ILOCK_EXCL);
|
|
out_invalidate:
|
|
xfs_vm_invalidatepage(page, 0);
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Write out a dirty page.
|
|
*
|
|
* For delalloc space on the page we need to allocate space and flush it.
|
|
* For unwritten space on the page we need to start the conversion to
|
|
* regular allocated space.
|
|
* For any other dirty buffer heads on the page we should flush them.
|
|
*/
|
|
STATIC int
|
|
xfs_vm_writepage(
|
|
struct page *page,
|
|
struct writeback_control *wbc)
|
|
{
|
|
struct inode *inode = page->mapping->host;
|
|
struct buffer_head *bh, *head;
|
|
struct xfs_bmbt_irec imap;
|
|
xfs_ioend_t *ioend = NULL, *iohead = NULL;
|
|
loff_t offset;
|
|
unsigned int type;
|
|
__uint64_t end_offset;
|
|
pgoff_t end_index, last_index;
|
|
ssize_t len;
|
|
int err, imap_valid = 0, uptodate = 1;
|
|
int count = 0;
|
|
int nonblocking = 0;
|
|
|
|
trace_xfs_writepage(inode, page, 0);
|
|
|
|
ASSERT(page_has_buffers(page));
|
|
|
|
/*
|
|
* Refuse to write the page out if we are called from reclaim context.
|
|
*
|
|
* This avoids stack overflows when called from deeply used stacks in
|
|
* random callers for direct reclaim or memcg reclaim. We explicitly
|
|
* allow reclaim from kswapd as the stack usage there is relatively low.
|
|
*
|
|
* This should never happen except in the case of a VM regression so
|
|
* warn about it.
|
|
*/
|
|
if (WARN_ON_ONCE((current->flags & (PF_MEMALLOC|PF_KSWAPD)) ==
|
|
PF_MEMALLOC))
|
|
goto redirty;
|
|
|
|
/*
|
|
* Given that we do not allow direct reclaim to call us, we should
|
|
* never be called while in a filesystem transaction.
|
|
*/
|
|
if (WARN_ON(current->flags & PF_FSTRANS))
|
|
goto redirty;
|
|
|
|
/* Is this page beyond the end of the file? */
|
|
offset = i_size_read(inode);
|
|
end_index = offset >> PAGE_CACHE_SHIFT;
|
|
last_index = (offset - 1) >> PAGE_CACHE_SHIFT;
|
|
if (page->index >= end_index) {
|
|
if ((page->index >= end_index + 1) ||
|
|
!(i_size_read(inode) & (PAGE_CACHE_SIZE - 1))) {
|
|
unlock_page(page);
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
end_offset = min_t(unsigned long long,
|
|
(xfs_off_t)(page->index + 1) << PAGE_CACHE_SHIFT,
|
|
offset);
|
|
len = 1 << inode->i_blkbits;
|
|
|
|
bh = head = page_buffers(page);
|
|
offset = page_offset(page);
|
|
type = IO_OVERWRITE;
|
|
|
|
if (wbc->sync_mode == WB_SYNC_NONE)
|
|
nonblocking = 1;
|
|
|
|
do {
|
|
int new_ioend = 0;
|
|
|
|
if (offset >= end_offset)
|
|
break;
|
|
if (!buffer_uptodate(bh))
|
|
uptodate = 0;
|
|
|
|
/*
|
|
* set_page_dirty dirties all buffers in a page, independent
|
|
* of their state. The dirty state however is entirely
|
|
* meaningless for holes (!mapped && uptodate), so skip
|
|
* buffers covering holes here.
|
|
*/
|
|
if (!buffer_mapped(bh) && buffer_uptodate(bh)) {
|
|
imap_valid = 0;
|
|
continue;
|
|
}
|
|
|
|
if (buffer_unwritten(bh)) {
|
|
if (type != IO_UNWRITTEN) {
|
|
type = IO_UNWRITTEN;
|
|
imap_valid = 0;
|
|
}
|
|
} else if (buffer_delay(bh)) {
|
|
if (type != IO_DELALLOC) {
|
|
type = IO_DELALLOC;
|
|
imap_valid = 0;
|
|
}
|
|
} else if (buffer_uptodate(bh)) {
|
|
if (type != IO_OVERWRITE) {
|
|
type = IO_OVERWRITE;
|
|
imap_valid = 0;
|
|
}
|
|
} else {
|
|
if (PageUptodate(page)) {
|
|
ASSERT(buffer_mapped(bh));
|
|
imap_valid = 0;
|
|
}
|
|
continue;
|
|
}
|
|
|
|
if (imap_valid)
|
|
imap_valid = xfs_imap_valid(inode, &imap, offset);
|
|
if (!imap_valid) {
|
|
/*
|
|
* If we didn't have a valid mapping then we need to
|
|
* put the new mapping into a separate ioend structure.
|
|
* This ensures non-contiguous extents always have
|
|
* separate ioends, which is particularly important
|
|
* for unwritten extent conversion at I/O completion
|
|
* time.
|
|
*/
|
|
new_ioend = 1;
|
|
err = xfs_map_blocks(inode, offset, &imap, type,
|
|
nonblocking);
|
|
if (err)
|
|
goto error;
|
|
imap_valid = xfs_imap_valid(inode, &imap, offset);
|
|
}
|
|
if (imap_valid) {
|
|
lock_buffer(bh);
|
|
if (type != IO_OVERWRITE)
|
|
xfs_map_at_offset(inode, bh, &imap, offset);
|
|
xfs_add_to_ioend(inode, bh, offset, type, &ioend,
|
|
new_ioend);
|
|
count++;
|
|
}
|
|
|
|
if (!iohead)
|
|
iohead = ioend;
|
|
|
|
} while (offset += len, ((bh = bh->b_this_page) != head));
|
|
|
|
if (uptodate && bh == head)
|
|
SetPageUptodate(page);
|
|
|
|
xfs_start_page_writeback(page, 1, count);
|
|
|
|
if (ioend && imap_valid) {
|
|
xfs_off_t end_index;
|
|
|
|
end_index = imap.br_startoff + imap.br_blockcount;
|
|
|
|
/* to bytes */
|
|
end_index <<= inode->i_blkbits;
|
|
|
|
/* to pages */
|
|
end_index = (end_index - 1) >> PAGE_CACHE_SHIFT;
|
|
|
|
/* check against file size */
|
|
if (end_index > last_index)
|
|
end_index = last_index;
|
|
|
|
xfs_cluster_write(inode, page->index + 1, &imap, &ioend,
|
|
wbc, end_index);
|
|
}
|
|
|
|
if (iohead)
|
|
xfs_submit_ioend(wbc, iohead);
|
|
|
|
return 0;
|
|
|
|
error:
|
|
if (iohead)
|
|
xfs_cancel_ioend(iohead);
|
|
|
|
if (err == -EAGAIN)
|
|
goto redirty;
|
|
|
|
xfs_aops_discard_page(page);
|
|
ClearPageUptodate(page);
|
|
unlock_page(page);
|
|
return err;
|
|
|
|
redirty:
|
|
redirty_page_for_writepage(wbc, page);
|
|
unlock_page(page);
|
|
return 0;
|
|
}
|
|
|
|
STATIC int
|
|
xfs_vm_writepages(
|
|
struct address_space *mapping,
|
|
struct writeback_control *wbc)
|
|
{
|
|
xfs_iflags_clear(XFS_I(mapping->host), XFS_ITRUNCATED);
|
|
return generic_writepages(mapping, wbc);
|
|
}
|
|
|
|
/*
|
|
* Called to move a page into cleanable state - and from there
|
|
* to be released. The page should already be clean. We always
|
|
* have buffer heads in this call.
|
|
*
|
|
* Returns 1 if the page is ok to release, 0 otherwise.
|
|
*/
|
|
STATIC int
|
|
xfs_vm_releasepage(
|
|
struct page *page,
|
|
gfp_t gfp_mask)
|
|
{
|
|
int delalloc, unwritten;
|
|
|
|
trace_xfs_releasepage(page->mapping->host, page, 0);
|
|
|
|
xfs_count_page_state(page, &delalloc, &unwritten);
|
|
|
|
if (WARN_ON(delalloc))
|
|
return 0;
|
|
if (WARN_ON(unwritten))
|
|
return 0;
|
|
|
|
return try_to_free_buffers(page);
|
|
}
|
|
|
|
STATIC int
|
|
__xfs_get_blocks(
|
|
struct inode *inode,
|
|
sector_t iblock,
|
|
struct buffer_head *bh_result,
|
|
int create,
|
|
int direct)
|
|
{
|
|
struct xfs_inode *ip = XFS_I(inode);
|
|
struct xfs_mount *mp = ip->i_mount;
|
|
xfs_fileoff_t offset_fsb, end_fsb;
|
|
int error = 0;
|
|
int lockmode = 0;
|
|
struct xfs_bmbt_irec imap;
|
|
int nimaps = 1;
|
|
xfs_off_t offset;
|
|
ssize_t size;
|
|
int new = 0;
|
|
|
|
if (XFS_FORCED_SHUTDOWN(mp))
|
|
return -XFS_ERROR(EIO);
|
|
|
|
offset = (xfs_off_t)iblock << inode->i_blkbits;
|
|
ASSERT(bh_result->b_size >= (1 << inode->i_blkbits));
|
|
size = bh_result->b_size;
|
|
|
|
if (!create && direct && offset >= i_size_read(inode))
|
|
return 0;
|
|
|
|
if (create) {
|
|
lockmode = XFS_ILOCK_EXCL;
|
|
xfs_ilock(ip, lockmode);
|
|
} else {
|
|
lockmode = xfs_ilock_map_shared(ip);
|
|
}
|
|
|
|
ASSERT(offset <= mp->m_maxioffset);
|
|
if (offset + size > mp->m_maxioffset)
|
|
size = mp->m_maxioffset - offset;
|
|
end_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)offset + size);
|
|
offset_fsb = XFS_B_TO_FSBT(mp, offset);
|
|
|
|
error = xfs_bmapi_read(ip, offset_fsb, end_fsb - offset_fsb,
|
|
&imap, &nimaps, XFS_BMAPI_ENTIRE);
|
|
if (error)
|
|
goto out_unlock;
|
|
|
|
if (create &&
|
|
(!nimaps ||
|
|
(imap.br_startblock == HOLESTARTBLOCK ||
|
|
imap.br_startblock == DELAYSTARTBLOCK))) {
|
|
if (direct) {
|
|
error = xfs_iomap_write_direct(ip, offset, size,
|
|
&imap, nimaps);
|
|
} else {
|
|
error = xfs_iomap_write_delay(ip, offset, size, &imap);
|
|
}
|
|
if (error)
|
|
goto out_unlock;
|
|
|
|
trace_xfs_get_blocks_alloc(ip, offset, size, 0, &imap);
|
|
} else if (nimaps) {
|
|
trace_xfs_get_blocks_found(ip, offset, size, 0, &imap);
|
|
} else {
|
|
trace_xfs_get_blocks_notfound(ip, offset, size);
|
|
goto out_unlock;
|
|
}
|
|
xfs_iunlock(ip, lockmode);
|
|
|
|
if (imap.br_startblock != HOLESTARTBLOCK &&
|
|
imap.br_startblock != DELAYSTARTBLOCK) {
|
|
/*
|
|
* For unwritten extents do not report a disk address on
|
|
* the read case (treat as if we're reading into a hole).
|
|
*/
|
|
if (create || !ISUNWRITTEN(&imap))
|
|
xfs_map_buffer(inode, bh_result, &imap, offset);
|
|
if (create && ISUNWRITTEN(&imap)) {
|
|
if (direct)
|
|
bh_result->b_private = inode;
|
|
set_buffer_unwritten(bh_result);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* If this is a realtime file, data may be on a different device.
|
|
* to that pointed to from the buffer_head b_bdev currently.
|
|
*/
|
|
bh_result->b_bdev = xfs_find_bdev_for_inode(inode);
|
|
|
|
/*
|
|
* If we previously allocated a block out beyond eof and we are now
|
|
* coming back to use it then we will need to flag it as new even if it
|
|
* has a disk address.
|
|
*
|
|
* With sub-block writes into unwritten extents we also need to mark
|
|
* the buffer as new so that the unwritten parts of the buffer gets
|
|
* correctly zeroed.
|
|
*/
|
|
if (create &&
|
|
((!buffer_mapped(bh_result) && !buffer_uptodate(bh_result)) ||
|
|
(offset >= i_size_read(inode)) ||
|
|
(new || ISUNWRITTEN(&imap))))
|
|
set_buffer_new(bh_result);
|
|
|
|
if (imap.br_startblock == DELAYSTARTBLOCK) {
|
|
BUG_ON(direct);
|
|
if (create) {
|
|
set_buffer_uptodate(bh_result);
|
|
set_buffer_mapped(bh_result);
|
|
set_buffer_delay(bh_result);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* If this is O_DIRECT or the mpage code calling tell them how large
|
|
* the mapping is, so that we can avoid repeated get_blocks calls.
|
|
*/
|
|
if (direct || size > (1 << inode->i_blkbits)) {
|
|
xfs_off_t mapping_size;
|
|
|
|
mapping_size = imap.br_startoff + imap.br_blockcount - iblock;
|
|
mapping_size <<= inode->i_blkbits;
|
|
|
|
ASSERT(mapping_size > 0);
|
|
if (mapping_size > size)
|
|
mapping_size = size;
|
|
if (mapping_size > LONG_MAX)
|
|
mapping_size = LONG_MAX;
|
|
|
|
bh_result->b_size = mapping_size;
|
|
}
|
|
|
|
return 0;
|
|
|
|
out_unlock:
|
|
xfs_iunlock(ip, lockmode);
|
|
return -error;
|
|
}
|
|
|
|
int
|
|
xfs_get_blocks(
|
|
struct inode *inode,
|
|
sector_t iblock,
|
|
struct buffer_head *bh_result,
|
|
int create)
|
|
{
|
|
return __xfs_get_blocks(inode, iblock, bh_result, create, 0);
|
|
}
|
|
|
|
STATIC int
|
|
xfs_get_blocks_direct(
|
|
struct inode *inode,
|
|
sector_t iblock,
|
|
struct buffer_head *bh_result,
|
|
int create)
|
|
{
|
|
return __xfs_get_blocks(inode, iblock, bh_result, create, 1);
|
|
}
|
|
|
|
/*
|
|
* Complete a direct I/O write request.
|
|
*
|
|
* If the private argument is non-NULL __xfs_get_blocks signals us that we
|
|
* need to issue a transaction to convert the range from unwritten to written
|
|
* extents. In case this is regular synchronous I/O we just call xfs_end_io
|
|
* to do this and we are done. But in case this was a successful AIO
|
|
* request this handler is called from interrupt context, from which we
|
|
* can't start transactions. In that case offload the I/O completion to
|
|
* the workqueues we also use for buffered I/O completion.
|
|
*/
|
|
STATIC void
|
|
xfs_end_io_direct_write(
|
|
struct kiocb *iocb,
|
|
loff_t offset,
|
|
ssize_t size,
|
|
void *private,
|
|
int ret,
|
|
bool is_async)
|
|
{
|
|
struct xfs_ioend *ioend = iocb->private;
|
|
|
|
/*
|
|
* While the generic direct I/O code updates the inode size, it does
|
|
* so only after the end_io handler is called, which means our
|
|
* end_io handler thinks the on-disk size is outside the in-core
|
|
* size. To prevent this just update it a little bit earlier here.
|
|
*/
|
|
if (offset + size > i_size_read(ioend->io_inode))
|
|
i_size_write(ioend->io_inode, offset + size);
|
|
|
|
/*
|
|
* blockdev_direct_IO can return an error even after the I/O
|
|
* completion handler was called. Thus we need to protect
|
|
* against double-freeing.
|
|
*/
|
|
iocb->private = NULL;
|
|
|
|
ioend->io_offset = offset;
|
|
ioend->io_size = size;
|
|
ioend->io_iocb = iocb;
|
|
ioend->io_result = ret;
|
|
if (private && size > 0)
|
|
ioend->io_type = IO_UNWRITTEN;
|
|
|
|
if (is_async) {
|
|
ioend->io_isasync = 1;
|
|
xfs_finish_ioend(ioend);
|
|
} else {
|
|
xfs_finish_ioend_sync(ioend);
|
|
}
|
|
}
|
|
|
|
STATIC ssize_t
|
|
xfs_vm_direct_IO(
|
|
int rw,
|
|
struct kiocb *iocb,
|
|
const struct iovec *iov,
|
|
loff_t offset,
|
|
unsigned long nr_segs)
|
|
{
|
|
struct inode *inode = iocb->ki_filp->f_mapping->host;
|
|
struct block_device *bdev = xfs_find_bdev_for_inode(inode);
|
|
ssize_t ret;
|
|
|
|
if (rw & WRITE) {
|
|
iocb->private = xfs_alloc_ioend(inode, IO_DIRECT);
|
|
|
|
ret = __blockdev_direct_IO(rw, iocb, inode, bdev, iov,
|
|
offset, nr_segs,
|
|
xfs_get_blocks_direct,
|
|
xfs_end_io_direct_write, NULL, 0);
|
|
if (ret != -EIOCBQUEUED && iocb->private)
|
|
xfs_destroy_ioend(iocb->private);
|
|
} else {
|
|
ret = __blockdev_direct_IO(rw, iocb, inode, bdev, iov,
|
|
offset, nr_segs,
|
|
xfs_get_blocks_direct,
|
|
NULL, NULL, 0);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
STATIC void
|
|
xfs_vm_write_failed(
|
|
struct address_space *mapping,
|
|
loff_t to)
|
|
{
|
|
struct inode *inode = mapping->host;
|
|
|
|
if (to > inode->i_size) {
|
|
/*
|
|
* Punch out the delalloc blocks we have already allocated.
|
|
*
|
|
* Don't bother with xfs_setattr given that nothing can have
|
|
* made it to disk yet as the page is still locked at this
|
|
* point.
|
|
*/
|
|
struct xfs_inode *ip = XFS_I(inode);
|
|
xfs_fileoff_t start_fsb;
|
|
xfs_fileoff_t end_fsb;
|
|
int error;
|
|
|
|
truncate_pagecache(inode, to, inode->i_size);
|
|
|
|
/*
|
|
* Check if there are any blocks that are outside of i_size
|
|
* that need to be trimmed back.
|
|
*/
|
|
start_fsb = XFS_B_TO_FSB(ip->i_mount, inode->i_size) + 1;
|
|
end_fsb = XFS_B_TO_FSB(ip->i_mount, to);
|
|
if (end_fsb <= start_fsb)
|
|
return;
|
|
|
|
xfs_ilock(ip, XFS_ILOCK_EXCL);
|
|
error = xfs_bmap_punch_delalloc_range(ip, start_fsb,
|
|
end_fsb - start_fsb);
|
|
if (error) {
|
|
/* something screwed, just bail */
|
|
if (!XFS_FORCED_SHUTDOWN(ip->i_mount)) {
|
|
xfs_alert(ip->i_mount,
|
|
"xfs_vm_write_failed: unable to clean up ino %lld",
|
|
ip->i_ino);
|
|
}
|
|
}
|
|
xfs_iunlock(ip, XFS_ILOCK_EXCL);
|
|
}
|
|
}
|
|
|
|
STATIC int
|
|
xfs_vm_write_begin(
|
|
struct file *file,
|
|
struct address_space *mapping,
|
|
loff_t pos,
|
|
unsigned len,
|
|
unsigned flags,
|
|
struct page **pagep,
|
|
void **fsdata)
|
|
{
|
|
int ret;
|
|
|
|
ret = block_write_begin(mapping, pos, len, flags | AOP_FLAG_NOFS,
|
|
pagep, xfs_get_blocks);
|
|
if (unlikely(ret))
|
|
xfs_vm_write_failed(mapping, pos + len);
|
|
return ret;
|
|
}
|
|
|
|
STATIC int
|
|
xfs_vm_write_end(
|
|
struct file *file,
|
|
struct address_space *mapping,
|
|
loff_t pos,
|
|
unsigned len,
|
|
unsigned copied,
|
|
struct page *page,
|
|
void *fsdata)
|
|
{
|
|
int ret;
|
|
|
|
ret = generic_write_end(file, mapping, pos, len, copied, page, fsdata);
|
|
if (unlikely(ret < len))
|
|
xfs_vm_write_failed(mapping, pos + len);
|
|
return ret;
|
|
}
|
|
|
|
STATIC sector_t
|
|
xfs_vm_bmap(
|
|
struct address_space *mapping,
|
|
sector_t block)
|
|
{
|
|
struct inode *inode = (struct inode *)mapping->host;
|
|
struct xfs_inode *ip = XFS_I(inode);
|
|
|
|
trace_xfs_vm_bmap(XFS_I(inode));
|
|
xfs_ilock(ip, XFS_IOLOCK_SHARED);
|
|
xfs_flush_pages(ip, (xfs_off_t)0, -1, 0, FI_REMAPF);
|
|
xfs_iunlock(ip, XFS_IOLOCK_SHARED);
|
|
return generic_block_bmap(mapping, block, xfs_get_blocks);
|
|
}
|
|
|
|
STATIC int
|
|
xfs_vm_readpage(
|
|
struct file *unused,
|
|
struct page *page)
|
|
{
|
|
return mpage_readpage(page, xfs_get_blocks);
|
|
}
|
|
|
|
STATIC int
|
|
xfs_vm_readpages(
|
|
struct file *unused,
|
|
struct address_space *mapping,
|
|
struct list_head *pages,
|
|
unsigned nr_pages)
|
|
{
|
|
return mpage_readpages(mapping, pages, nr_pages, xfs_get_blocks);
|
|
}
|
|
|
|
const struct address_space_operations xfs_address_space_operations = {
|
|
.readpage = xfs_vm_readpage,
|
|
.readpages = xfs_vm_readpages,
|
|
.writepage = xfs_vm_writepage,
|
|
.writepages = xfs_vm_writepages,
|
|
.releasepage = xfs_vm_releasepage,
|
|
.invalidatepage = xfs_vm_invalidatepage,
|
|
.write_begin = xfs_vm_write_begin,
|
|
.write_end = xfs_vm_write_end,
|
|
.bmap = xfs_vm_bmap,
|
|
.direct_IO = xfs_vm_direct_IO,
|
|
.migratepage = buffer_migrate_page,
|
|
.is_partially_uptodate = block_is_partially_uptodate,
|
|
.error_remove_page = generic_error_remove_page,
|
|
};
|