diff options
Diffstat (limited to 'fs/xfs/linux-2.6/xfs_aops.c')
| -rw-r--r-- | fs/xfs/linux-2.6/xfs_aops.c | 1499 |
1 files changed, 0 insertions, 1499 deletions
diff --git a/fs/xfs/linux-2.6/xfs_aops.c b/fs/xfs/linux-2.6/xfs_aops.c deleted file mode 100644 index 63e971e..0000000 --- a/fs/xfs/linux-2.6/xfs_aops.c +++ /dev/null @@ -1,1499 +0,0 @@ -/* - * 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> - - -/* - * Prime number of hash buckets since address is used as the key. - */ -#define NVSYNC 37 -#define to_ioend_wq(v) (&xfs_ioend_wq[((unsigned long)v) % NVSYNC]) -static wait_queue_head_t xfs_ioend_wq[NVSYNC]; - -void __init -xfs_ioend_init(void) -{ - int i; - - for (i = 0; i < NVSYNC; i++) - init_waitqueue_head(&xfs_ioend_wq[i]); -} - -void -xfs_ioend_wait( - xfs_inode_t *ip) -{ - wait_queue_head_t *wq = to_ioend_wq(ip); - - wait_event(*wq, (atomic_read(&ip->i_iocount) == 0)); -} - -STATIC void -xfs_ioend_wake( - xfs_inode_t *ip) -{ - if (atomic_dec_and_test(&ip->i_iocount)) - wake_up(to_ioend_wq(ip)); -} - -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; - struct xfs_inode *ip = XFS_I(ioend->io_inode); - - for (bh = ioend->io_buffer_head; bh; bh = next) { - next = bh->b_private; - bh->b_end_io(bh, !ioend->io_error); - } - - /* - * Volume managers supporting multiple paths can send back ENODEV - * when the final path disappears. In this case continuing to fill - * the page cache with dirty data which cannot be written out is - * evil, so prevent that. - */ - if (unlikely(ioend->io_error == -ENODEV)) { - xfs_do_force_shutdown(ip->i_mount, SHUTDOWN_DEVICE_REQ, - __FILE__, __LINE__); - } - - xfs_ioend_wake(ip); - 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 = MAX(ip->i_size, ip->i_new_size); - isize = MIN(isize, bsize); - return isize > ip->i_d.di_size ? isize : 0; -} - -/* - * Update on-disk file size now that data has been written to disk. The - * current in-memory file size is i_size. If a write is beyond eof i_new_size - * will be the intended file size until i_size is updated. If this write does - * not extend all the way to the valid file size then restrict this update to - * the end of the write. - * - * 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 (unlikely(ioend->io_error)) - return 0; - - 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. - */ -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 - queue_work(xfsdatad_workqueue, &ioend->io_work); - } -} - -/* - * 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; - - /* - * 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 && - likely(!ioend->io_error && !XFS_FORCED_SHUTDOWN(ip->i_mount))) { - - error = xfs_iomap_write_unwritten(ip, ioend->io_offset, - ioend->io_size); - if (error) - ioend->io_error = error; - } - - /* - * We might have to update the on-disk file size after extending - * writes. - */ - error = xfs_setfilesize(ioend); - ASSERT(!error || error == EAGAIN); - - /* - * 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 { - if (ioend->io_iocb) - aio_complete(ioend->io_iocb, ioend->io_result, 0); - 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_error = 0; - ioend->io_list = NULL; - ioend->io_type = type; - ioend->io_inode = inode; - ioend->io_buffer_head = NULL; - ioend->io_buffer_tail = NULL; - atomic_inc(&XFS_I(ioend->io_inode)->i_iocount); - 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(NULL, ip, offset_fsb, end_fsb - offset_fsb, - bmapi_flags, NULL, 0, imap, &nimaps, NULL); - 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); - - xfs_ioend_wake(XFS_I(ioend->io_inode)); - 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 really be done by the core VM, but until that happens - * filesystems like XFS, btrfs and ext4 have to take care of this - * by themselves. - */ - if ((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(NULL, ip, offset_fsb, end_fsb - offset_fsb, - XFS_BMAPI_ENTIRE, NULL, 0, &imap, &nimaps, NULL); - 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; - - /* - * 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; - if (private && size > 0) - ioend->io_type = IO_UNWRITTEN; - - if (is_async) { - /* - * If we are converting an unwritten extent we need to delay - * the AIO completion until after the unwrittent extent - * conversion has completed, otherwise do it ASAP. - */ - if (ioend->io_type == IO_UNWRITTEN) { - ioend->io_iocb = iocb; - ioend->io_result = ret; - } else { - aio_complete(iocb, ret, 0); - } - xfs_finish_ioend(ioend); - } else { - xfs_finish_ioend_sync(ioend); - } - - /* XXX: probably should move into the real I/O completion handler */ - inode_dio_done(ioend->io_inode); -} - -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. We - * don't call xfs_setattr() to do this as we may be in the - * middle of a multi-iovec write and so the vfs inode->i_size - * will not match the xfs ip->i_size and so it will zero too - * much. Hence we jus truncate the page cache to zero what is - * necessary and punch the delalloc blocks directly. - */ - 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, -}; |
