| // SPDX-License-Identifier: GPL-2.0 | |
| /* | |
| * Copyright (c) 2000-2005 Silicon Graphics, Inc. | |
| * Copyright (c) 2016-2025 Christoph Hellwig. | |
| * All Rights Reserved. | |
| */ | |
| #include "xfs_platform.h" | |
| #include "xfs_shared.h" | |
| #include "xfs_format.h" | |
| #include "xfs_log_format.h" | |
| #include "xfs_trans_resv.h" | |
| #include "xfs_mount.h" | |
| #include "xfs_inode.h" | |
| #include "xfs_trans.h" | |
| #include "xfs_iomap.h" | |
| #include "xfs_trace.h" | |
| #include "xfs_bmap.h" | |
| #include "xfs_bmap_util.h" | |
| #include "xfs_reflink.h" | |
| #include "xfs_errortag.h" | |
| #include "xfs_error.h" | |
| #include "xfs_icache.h" | |
| #include "xfs_ioend.h" | |
| #include "xfs_zone_alloc.h" | |
| #include "xfs_rtgroup.h" | |
| #include <linux/bio-integrity.h> | |
| struct xfs_writepage_ctx { | |
| struct iomap_writepage_ctx ctx; | |
| unsigned int data_seq; | |
| unsigned int cow_seq; | |
| }; | |
| static inline struct xfs_writepage_ctx * | |
| XFS_WPC(struct iomap_writepage_ctx *ctx) | |
| { | |
| return container_of(ctx, struct xfs_writepage_ctx, ctx); | |
| } | |
| /* | |
| * Update on-disk file size now that data has been written to disk. | |
| */ | |
| int | |
| xfs_setfilesize( | |
| struct xfs_inode *ip, | |
| xfs_off_t offset, | |
| size_t size) | |
| { | |
| struct xfs_mount *mp = ip->i_mount; | |
| struct xfs_trans *tp; | |
| xfs_fsize_t isize; | |
| int error; | |
| error = xfs_trans_alloc(mp, &M_RES(mp)->tr_fsyncts, 0, 0, 0, &tp); | |
| if (error) | |
| return error; | |
| xfs_ilock(ip, XFS_ILOCK_EXCL); | |
| isize = xfs_new_eof(ip, offset + size); | |
| if (!isize) { | |
| xfs_iunlock(ip, XFS_ILOCK_EXCL); | |
| xfs_trans_cancel(tp); | |
| return 0; | |
| } | |
| trace_xfs_setfilesize(ip, offset, size); | |
| ip->i_disk_size = isize; | |
| xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL); | |
| xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); | |
| return xfs_trans_commit(tp); | |
| } | |
| /* | |
| * We cannot cancel the ioend directly on error. We may have already set other | |
| * pages under writeback and hence we have to run I/O completion to mark the | |
| * error state of the pages under writeback appropriately. | |
| * | |
| * If the folio has delalloc blocks on it, the caller is asking us to punch them | |
| * out. If we don't, we can leave a stale delalloc mapping covered by a clean | |
| * page that needs to be dirtied again before the delalloc mapping can be | |
| * converted. This stale delalloc mapping can trip up a later direct I/O read | |
| * operation on the same region. | |
| * | |
| * We prevent this by truncating away the delalloc regions on the folio. 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). | |
| */ | |
| static void | |
| xfs_discard_folio( | |
| struct folio *folio, | |
| loff_t pos) | |
| { | |
| struct xfs_inode *ip = XFS_I(folio->mapping->host); | |
| struct xfs_mount *mp = ip->i_mount; | |
| if (xfs_is_shutdown(mp)) | |
| return; | |
| xfs_alert_ratelimited(mp, | |
| "page discard on page "PTR_FMT", inode 0x%llx, pos %llu.", | |
| folio, I_INO(ip), pos); | |
| /* | |
| * The end of the punch range is always the offset of the first | |
| * byte of the next folio. Hence the end offset is only dependent on the | |
| * folio itself and not the start offset that is passed in. | |
| */ | |
| xfs_bmap_punch_delalloc_range(ip, XFS_DATA_FORK, pos, | |
| folio_next_pos(folio), NULL); | |
| } | |
| /* | |
| * Fast revalidation of the cached writeback mapping. Return true if the current | |
| * mapping is valid, false otherwise. | |
| */ | |
| static bool | |
| xfs_imap_valid( | |
| struct iomap_writepage_ctx *wpc, | |
| struct xfs_inode *ip, | |
| loff_t offset) | |
| { | |
| if (offset < wpc->iomap.offset || | |
| offset >= wpc->iomap.offset + wpc->iomap.length) | |
| return false; | |
| /* | |
| * If this is a COW mapping, it is sufficient to check that the mapping | |
| * covers the offset. Be careful to check this first because the caller | |
| * can revalidate a COW mapping without updating the data seqno. | |
| */ | |
| if (wpc->iomap.flags & IOMAP_F_SHARED) | |
| return true; | |
| /* | |
| * This is not a COW mapping. Check the sequence number of the data fork | |
| * because concurrent changes could have invalidated the extent. Check | |
| * the COW fork because concurrent changes since the last time we | |
| * checked (and found nothing at this offset) could have added | |
| * overlapping blocks. | |
| */ | |
| if (XFS_WPC(wpc)->data_seq != READ_ONCE(ip->i_df.if_seq)) { | |
| trace_xfs_wb_data_iomap_invalid(ip, &wpc->iomap, | |
| XFS_WPC(wpc)->data_seq, XFS_DATA_FORK); | |
| return false; | |
| } | |
| if (xfs_inode_has_cow_data(ip) && | |
| XFS_WPC(wpc)->cow_seq != READ_ONCE(ip->i_cowfp->if_seq)) { | |
| trace_xfs_wb_cow_iomap_invalid(ip, &wpc->iomap, | |
| XFS_WPC(wpc)->cow_seq, XFS_COW_FORK); | |
| return false; | |
| } | |
| return true; | |
| } | |
| static int | |
| xfs_map_blocks( | |
| struct iomap_writepage_ctx *wpc, | |
| loff_t offset, | |
| unsigned int len) | |
| { | |
| struct xfs_inode *ip = XFS_I(wpc->inode); | |
| struct xfs_mount *mp = ip->i_mount; | |
| ssize_t count = i_blocksize(wpc->inode); | |
| xfs_fileoff_t offset_fsb = XFS_B_TO_FSBT(mp, offset); | |
| xfs_fileoff_t end_fsb = XFS_B_TO_FSB(mp, offset + count); | |
| xfs_fileoff_t cow_fsb; | |
| int whichfork; | |
| struct xfs_bmbt_irec imap; | |
| struct xfs_iext_cursor icur; | |
| int retries = 0; | |
| int error = 0; | |
| unsigned int *seq; | |
| if (xfs_is_shutdown(mp)) | |
| return -EIO; | |
| XFS_ERRORTAG_DELAY(mp, XFS_ERRTAG_WB_DELAY_MS); | |
| /* | |
| * COW fork blocks can overlap data fork blocks even if the blocks | |
| * aren't shared. COW I/O always takes precedent, so we must always | |
| * check for overlap on reflink inodes unless the mapping is already a | |
| * COW one, or the COW fork hasn't changed from the last time we looked | |
| * at it. | |
| * | |
| * It's safe to check the COW fork if_seq here without the ILOCK because | |
| * we've indirectly protected against concurrent updates: writeback has | |
| * the page locked, which prevents concurrent invalidations by reflink | |
| * and directio and prevents concurrent buffered writes to the same | |
| * page. Changes to if_seq always happen under i_lock, which protects | |
| * against concurrent updates and provides a memory barrier on the way | |
| * out that ensures that we always see the current value. | |
| */ | |
| if (xfs_imap_valid(wpc, ip, offset)) | |
| return 0; | |
| /* | |
| * If we don't have a valid map, now it's time to get a new one for this | |
| * offset. This will convert delayed allocations (including COW ones) | |
| * into real extents. If we return without a valid map, it means we | |
| * landed in a hole and we skip the block. | |
| */ | |
| retry: | |
| cow_fsb = NULLFILEOFF; | |
| whichfork = XFS_DATA_FORK; | |
| xfs_ilock(ip, XFS_ILOCK_SHARED); | |
| ASSERT(!xfs_need_iread_extents(&ip->i_df)); | |
| /* | |
| * Check if this is offset is covered by a COW extents, and if yes use | |
| * it directly instead of looking up anything in the data fork. | |
| */ | |
| if (xfs_inode_has_cow_data(ip) && | |
| xfs_iext_lookup_extent(ip, ip->i_cowfp, offset_fsb, &icur, &imap)) | |
| cow_fsb = imap.br_startoff; | |
| if (cow_fsb != NULLFILEOFF && cow_fsb <= offset_fsb) { | |
| XFS_WPC(wpc)->cow_seq = READ_ONCE(ip->i_cowfp->if_seq); | |
| xfs_iunlock(ip, XFS_ILOCK_SHARED); | |
| whichfork = XFS_COW_FORK; | |
| goto allocate_blocks; | |
| } | |
| /* | |
| * No COW extent overlap. Revalidate now that we may have updated | |
| * ->cow_seq. If the data mapping is still valid, we're done. | |
| */ | |
| if (xfs_imap_valid(wpc, ip, offset)) { | |
| xfs_iunlock(ip, XFS_ILOCK_SHARED); | |
| return 0; | |
| } | |
| /* | |
| * If we don't have a valid map, now it's time to get a new one for this | |
| * offset. This will convert delayed allocations (including COW ones) | |
| * into real extents. | |
| */ | |
| if (!xfs_iext_lookup_extent(ip, &ip->i_df, offset_fsb, &icur, &imap)) | |
| imap.br_startoff = end_fsb; /* fake a hole past EOF */ | |
| XFS_WPC(wpc)->data_seq = READ_ONCE(ip->i_df.if_seq); | |
| xfs_iunlock(ip, XFS_ILOCK_SHARED); | |
| /* landed in a hole or beyond EOF? */ | |
| if (imap.br_startoff > offset_fsb) { | |
| imap.br_blockcount = imap.br_startoff - offset_fsb; | |
| imap.br_startoff = offset_fsb; | |
| imap.br_startblock = HOLESTARTBLOCK; | |
| imap.br_state = XFS_EXT_NORM; | |
| } | |
| /* | |
| * Truncate to the next COW extent if there is one. This is the only | |
| * opportunity to do this because we can skip COW fork lookups for the | |
| * subsequent blocks in the mapping; however, the requirement to treat | |
| * the COW range separately remains. | |
| */ | |
| if (cow_fsb != NULLFILEOFF && | |
| cow_fsb < imap.br_startoff + imap.br_blockcount) | |
| imap.br_blockcount = cow_fsb - imap.br_startoff; | |
| /* got a delalloc extent? */ | |
| if (imap.br_startblock != HOLESTARTBLOCK && | |
| isnullstartblock(imap.br_startblock)) | |
| goto allocate_blocks; | |
| xfs_bmbt_to_iomap(ip, &wpc->iomap, &imap, 0, 0, XFS_WPC(wpc)->data_seq); | |
| trace_xfs_map_blocks_found(ip, offset, count, whichfork, &imap); | |
| return 0; | |
| allocate_blocks: | |
| /* | |
| * Convert a dellalloc extent to a real one. The current page is held | |
| * locked so nothing could have removed the block backing offset_fsb, | |
| * although it could have moved from the COW to the data fork by another | |
| * thread. | |
| */ | |
| if (whichfork == XFS_COW_FORK) | |
| seq = &XFS_WPC(wpc)->cow_seq; | |
| else | |
| seq = &XFS_WPC(wpc)->data_seq; | |
| error = xfs_bmapi_convert_delalloc(ip, whichfork, offset, | |
| &wpc->iomap, seq); | |
| if (error) { | |
| /* | |
| * If we failed to find the extent in the COW fork we might have | |
| * raced with a COW to data fork conversion or truncate. | |
| * Restart the lookup to catch the extent in the data fork for | |
| * the former case, but prevent additional retries to avoid | |
| * looping forever for the latter case. | |
| */ | |
| if (error == -EAGAIN && whichfork == XFS_COW_FORK && !retries++) | |
| goto retry; | |
| ASSERT(error != -EAGAIN); | |
| return error; | |
| } | |
| /* | |
| * Due to merging the return real extent might be larger than the | |
| * original delalloc one. Trim the return extent to the next COW | |
| * boundary again to force a re-lookup. | |
| */ | |
| if (whichfork != XFS_COW_FORK && cow_fsb != NULLFILEOFF) { | |
| loff_t cow_offset = XFS_FSB_TO_B(mp, cow_fsb); | |
| if (cow_offset < wpc->iomap.offset + wpc->iomap.length) | |
| wpc->iomap.length = cow_offset - wpc->iomap.offset; | |
| } | |
| ASSERT(wpc->iomap.offset <= offset); | |
| ASSERT(wpc->iomap.offset + wpc->iomap.length > offset); | |
| trace_xfs_map_blocks_alloc(ip, offset, count, whichfork, &imap); | |
| return 0; | |
| } | |
| static ssize_t | |
| xfs_writeback_range( | |
| struct iomap_writepage_ctx *wpc, | |
| struct folio *folio, | |
| u64 offset, | |
| unsigned int len, | |
| u64 end_pos) | |
| { | |
| ssize_t ret; | |
| ret = xfs_map_blocks(wpc, offset, len); | |
| if (!ret) | |
| ret = iomap_add_to_ioend(wpc, folio, offset, end_pos, len); | |
| if (ret < 0) | |
| xfs_discard_folio(folio, offset); | |
| return ret; | |
| } | |
| static bool | |
| xfs_ioend_needs_wq_completion( | |
| struct iomap_ioend *ioend) | |
| { | |
| /* Changing inode size requires a transaction. */ | |
| if (xfs_ioend_is_append(ioend)) | |
| return true; | |
| /* Extent manipulation requires a transaction. */ | |
| if (ioend->io_flags & (IOMAP_IOEND_UNWRITTEN | IOMAP_IOEND_SHARED)) | |
| return true; | |
| return false; | |
| } | |
| static int | |
| xfs_writeback_submit( | |
| struct iomap_writepage_ctx *wpc, | |
| int error) | |
| { | |
| struct iomap_ioend *ioend = wpc->wb_ctx; | |
| /* | |
| * Convert CoW extents to regular. | |
| * | |
| * We can allocate memory here while doing writeback on behalf of memory | |
| * reclaim. To avoid memory allocation deadlocks, set the task-wide | |
| * nofs context. | |
| */ | |
| if (!error && (ioend->io_flags & IOMAP_IOEND_SHARED)) { | |
| unsigned int nofs_flag; | |
| nofs_flag = memalloc_nofs_save(); | |
| error = xfs_reflink_convert_cow(XFS_I(ioend->io_inode), | |
| ioend->io_offset, ioend->io_size); | |
| memalloc_nofs_restore(nofs_flag); | |
| } | |
| /* | |
| * Send ioends that might require a transaction to the completion wq, | |
| * and disable the block layer task completion for them as there is no | |
| * need to defer twice. | |
| */ | |
| if (xfs_ioend_needs_wq_completion(ioend)) { | |
| ioend->io_bio.bi_end_io = xfs_end_bio; | |
| bio_clear_flag(&ioend->io_bio, BIO_COMPLETE_IN_TASK); | |
| } | |
| return iomap_ioend_writeback_submit(wpc, error); | |
| } | |
| static const struct iomap_writeback_ops xfs_writeback_ops = { | |
| .writeback_range = xfs_writeback_range, | |
| .writeback_submit = xfs_writeback_submit, | |
| }; | |
| struct xfs_zoned_writepage_ctx { | |
| struct iomap_writepage_ctx ctx; | |
| struct xfs_open_zone *open_zone; | |
| }; | |
| static inline struct xfs_zoned_writepage_ctx * | |
| XFS_ZWPC(struct iomap_writepage_ctx *ctx) | |
| { | |
| return container_of(ctx, struct xfs_zoned_writepage_ctx, ctx); | |
| } | |
| static int | |
| xfs_zoned_map_blocks( | |
| struct iomap_writepage_ctx *wpc, | |
| loff_t offset, | |
| unsigned int len) | |
| { | |
| struct xfs_inode *ip = XFS_I(wpc->inode); | |
| struct xfs_mount *mp = ip->i_mount; | |
| xfs_fileoff_t offset_fsb = XFS_B_TO_FSBT(mp, offset); | |
| xfs_fileoff_t end_fsb = XFS_B_TO_FSB(mp, offset + len); | |
| xfs_filblks_t count_fsb; | |
| struct xfs_bmbt_irec imap, del; | |
| struct xfs_iext_cursor icur; | |
| if (xfs_is_shutdown(mp)) | |
| return -EIO; | |
| XFS_ERRORTAG_DELAY(mp, XFS_ERRTAG_WB_DELAY_MS); | |
| /* | |
| * All dirty data must be covered by delalloc extents. But truncate can | |
| * remove delalloc extents underneath us or reduce their size. | |
| * Returning a hole tells iomap to not write back any data from this | |
| * range, which is the right thing to do in that case. | |
| * | |
| * Otherwise just tell iomap to treat ranges previously covered by a | |
| * delalloc extent as mapped. The actual block allocation will be done | |
| * just before submitting the bio. | |
| * | |
| * This implies we never map outside folios that are locked or marked | |
| * as under writeback, and thus there is no need check the fork sequence | |
| * count here. | |
| */ | |
| xfs_ilock(ip, XFS_ILOCK_EXCL); | |
| if (!xfs_iext_lookup_extent(ip, ip->i_cowfp, offset_fsb, &icur, &imap)) | |
| imap.br_startoff = end_fsb; /* fake a hole past EOF */ | |
| if (imap.br_startoff > offset_fsb) { | |
| imap.br_blockcount = imap.br_startoff - offset_fsb; | |
| imap.br_startoff = offset_fsb; | |
| imap.br_startblock = HOLESTARTBLOCK; | |
| imap.br_state = XFS_EXT_NORM; | |
| xfs_iunlock(ip, XFS_ILOCK_EXCL); | |
| xfs_bmbt_to_iomap(ip, &wpc->iomap, &imap, 0, 0, 0); | |
| return 0; | |
| } | |
| end_fsb = min(end_fsb, imap.br_startoff + imap.br_blockcount); | |
| count_fsb = end_fsb - offset_fsb; | |
| del = imap; | |
| xfs_trim_extent(&del, offset_fsb, count_fsb); | |
| xfs_bmap_del_extent_delay(ip, XFS_COW_FORK, &icur, &imap, &del, | |
| XFS_BMAPI_REMAP); | |
| xfs_iunlock(ip, XFS_ILOCK_EXCL); | |
| xfs_iomap_set_anon_write(ip, &wpc->iomap, offset, | |
| XFS_FSB_TO_B(mp, count_fsb)); | |
| trace_xfs_zoned_map_blocks(ip, offset, wpc->iomap.length); | |
| return 0; | |
| } | |
| static ssize_t | |
| xfs_zoned_writeback_range( | |
| struct iomap_writepage_ctx *wpc, | |
| struct folio *folio, | |
| u64 offset, | |
| unsigned int len, | |
| u64 end_pos) | |
| { | |
| ssize_t ret; | |
| ret = xfs_zoned_map_blocks(wpc, offset, len); | |
| if (!ret) | |
| ret = iomap_add_to_ioend(wpc, folio, offset, end_pos, len); | |
| if (ret < 0) | |
| xfs_discard_folio(folio, offset); | |
| return ret; | |
| } | |
| static int | |
| xfs_zoned_writeback_submit( | |
| struct iomap_writepage_ctx *wpc, | |
| int error) | |
| { | |
| struct iomap_ioend *ioend = wpc->wb_ctx; | |
| /* | |
| * Defer all completions to our workqueue as all zoned writes require a | |
| * transaction to be persisted. This also means we never need the block | |
| * layer in-task completion for a task context. | |
| */ | |
| ioend->io_bio.bi_end_io = xfs_end_bio; | |
| bio_clear_flag(&ioend->io_bio, BIO_COMPLETE_IN_TASK); | |
| if (error) { | |
| ioend->io_bio.bi_status = errno_to_blk_status(error); | |
| bio_endio(&ioend->io_bio); | |
| return error; | |
| } | |
| if (wpc->iomap.flags & IOMAP_F_INTEGRITY) | |
| fs_bio_integrity_generate(&ioend->io_bio); | |
| xfs_zone_alloc_and_submit(ioend, &XFS_ZWPC(wpc)->open_zone); | |
| return 0; | |
| } | |
| static const struct iomap_writeback_ops xfs_zoned_writeback_ops = { | |
| .writeback_range = xfs_zoned_writeback_range, | |
| .writeback_submit = xfs_zoned_writeback_submit, | |
| }; | |
| STATIC int | |
| xfs_vm_writepages( | |
| struct address_space *mapping, | |
| struct writeback_control *wbc) | |
| { | |
| struct xfs_inode *ip = XFS_I(mapping->host); | |
| xfs_iflags_clear(ip, XFS_ITRUNCATED); | |
| if (xfs_is_zoned_inode(ip)) { | |
| struct xfs_zoned_writepage_ctx xc = { | |
| .ctx = { | |
| .inode = mapping->host, | |
| .wbc = wbc, | |
| .ops = &xfs_zoned_writeback_ops | |
| }, | |
| }; | |
| int error; | |
| error = iomap_writepages(&xc.ctx); | |
| if (xc.open_zone) | |
| xfs_open_zone_put(xc.open_zone); | |
| return error; | |
| } else { | |
| struct xfs_writepage_ctx wpc = { | |
| .ctx = { | |
| .inode = mapping->host, | |
| .wbc = wbc, | |
| .ops = &xfs_writeback_ops | |
| }, | |
| }; | |
| return iomap_writepages(&wpc.ctx); | |
| } | |
| } | |
| STATIC int | |
| xfs_dax_writepages( | |
| struct address_space *mapping, | |
| struct writeback_control *wbc) | |
| { | |
| struct xfs_inode *ip = XFS_I(mapping->host); | |
| xfs_iflags_clear(ip, XFS_ITRUNCATED); | |
| return dax_writeback_mapping_range(mapping, | |
| xfs_inode_buftarg(ip)->bt_daxdev, wbc); | |
| } | |
| STATIC sector_t | |
| xfs_vm_bmap( | |
| struct address_space *mapping, | |
| sector_t block) | |
| { | |
| struct xfs_inode *ip = XFS_I(mapping->host); | |
| trace_xfs_vm_bmap(ip); | |
| /* | |
| * The swap code (ab-)uses ->bmap to get a block mapping and then | |
| * bypasses the file system for actual I/O. We really can't allow | |
| * that on reflinks inodes, so we have to skip out here. And yes, | |
| * 0 is the magic code for a bmap error. | |
| * | |
| * Since we don't pass back blockdev info, we can't return bmap | |
| * information for rt files either. | |
| */ | |
| if (xfs_is_cow_inode(ip) || XFS_IS_REALTIME_INODE(ip)) | |
| return 0; | |
| return iomap_bmap(mapping, block, &xfs_read_iomap_ops); | |
| } | |
| static void | |
| xfs_bio_submit_read( | |
| const struct iomap_iter *iter, | |
| struct iomap_read_folio_ctx *ctx) | |
| { | |
| struct bio *bio = ctx->read_ctx; | |
| /* defer read completions to the ioend workqueue */ | |
| iomap_init_ioend(iter->inode, bio, ctx->read_ctx_file_offset, 0); | |
| iomap_bio_submit_read_endio(iter, ctx, xfs_end_bio); | |
| } | |
| static const struct iomap_read_ops xfs_iomap_read_ops = { | |
| .read_folio_range = iomap_bio_read_folio_range, | |
| .submit_read = xfs_bio_submit_read, | |
| .bio_set = &iomap_ioend_bioset, | |
| }; | |
| static inline const struct iomap_read_ops * | |
| xfs_get_iomap_read_ops( | |
| const struct address_space *mapping) | |
| { | |
| struct xfs_inode *ip = XFS_I(mapping->host); | |
| if (bdev_has_integrity_csum(xfs_inode_buftarg(ip)->bt_bdev)) | |
| return &xfs_iomap_read_ops; | |
| return &iomap_bio_read_ops; | |
| } | |
| STATIC int | |
| xfs_vm_read_folio( | |
| struct file *file, | |
| struct folio *folio) | |
| { | |
| struct iomap_read_folio_ctx ctx = { .cur_folio = folio }; | |
| ctx.ops = xfs_get_iomap_read_ops(folio->mapping); | |
| iomap_read_folio(&xfs_read_iomap_ops, &ctx, NULL); | |
| return 0; | |
| } | |
| STATIC void | |
| xfs_vm_readahead( | |
| struct readahead_control *rac) | |
| { | |
| struct iomap_read_folio_ctx ctx = { .rac = rac }; | |
| ctx.ops = xfs_get_iomap_read_ops(rac->mapping), | |
| iomap_readahead(&xfs_read_iomap_ops, &ctx, NULL); | |
| } | |
| static int | |
| xfs_vm_swap_activate( | |
| struct swap_info_struct *sis, | |
| struct file *swap_file, | |
| sector_t *span) | |
| { | |
| struct xfs_inode *ip = XFS_I(file_inode(swap_file)); | |
| if (xfs_is_zoned_inode(ip)) | |
| return -EINVAL; | |
| /* | |
| * Swap file activation can race against concurrent shared extent | |
| * removal in files that have been cloned. If this happens, | |
| * iomap_swapfile_iter() can fail because it encountered a shared | |
| * extent even though an operation is in progress to remove those | |
| * shared extents. | |
| * | |
| * This race becomes problematic when we defer extent removal | |
| * operations beyond the end of a syscall (i.e. use async background | |
| * processing algorithms). Users think the extents are no longer | |
| * shared, but iomap_swapfile_iter() still sees them as shared | |
| * because the refcountbt entries for the extents being removed have | |
| * not yet been updated. Hence the swapon call fails unexpectedly. | |
| * | |
| * The race condition is currently most obvious from the unlink() | |
| * operation as extent removal is deferred until after the last | |
| * reference to the inode goes away. We then process the extent | |
| * removal asynchronously, hence triggers the "syscall completed but | |
| * work not done" condition mentioned above. To close this race | |
| * window, we need to flush any pending inodegc operations to ensure | |
| * they have updated the refcountbt records before we try to map the | |
| * swapfile. | |
| */ | |
| xfs_inodegc_flush(ip->i_mount); | |
| /* | |
| * Direct the swap code to the correct block device when this file | |
| * sits on the RT device. | |
| */ | |
| sis->bdev = xfs_inode_buftarg(ip)->bt_bdev; | |
| return iomap_swapfile_activate(sis, swap_file, span, | |
| &xfs_read_iomap_ops); | |
| } | |
| const struct address_space_operations xfs_address_space_operations = { | |
| .read_folio = xfs_vm_read_folio, | |
| .readahead = xfs_vm_readahead, | |
| .writepages = xfs_vm_writepages, | |
| .dirty_folio = iomap_dirty_folio, | |
| .release_folio = iomap_release_folio, | |
| .invalidate_folio = iomap_invalidate_folio, | |
| .bmap = xfs_vm_bmap, | |
| .migrate_folio = filemap_migrate_folio, | |
| .is_partially_uptodate = iomap_is_partially_uptodate, | |
| .error_remove_folio = generic_error_remove_folio, | |
| .swap_activate = xfs_vm_swap_activate, | |
| }; | |
| const struct address_space_operations xfs_dax_aops = { | |
| .writepages = xfs_dax_writepages, | |
| .dirty_folio = noop_dirty_folio, | |
| .swap_activate = xfs_vm_swap_activate, | |
| }; |