Use read ioends for fsverity verification. Do not issue fsverity metadata I/O through the same workqueue due to risk of a deadlock by a filled workqueue. Pass fsverity_info from iomap context down to the ioend as hashtable lookups are expensive. Add a simple helper to check that this is not fsverity metadata but file data that needs verification. Signed-off-by: Andrey Albershteyn --- fs/xfs/xfs_aops.c | 13 ++++++++----- fs/xfs/xfs_file.c | 3 ++- fs/xfs/xfs_fsverity.c | 9 +++++++++ fs/xfs/xfs_fsverity.h | 6 ++++++ fs/xfs/xfs_ioend.c | 42 +++++++++++++++++++++++++++++++++++++++++- fs/xfs/xfs_ioend.h | 4 +++- include/linux/iomap.h | 1 + 7 files changed, 70 insertions(+), 8 deletions(-) diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c index b8813e577285..14bfaed1f1f6 100644 --- a/fs/xfs/xfs_aops.c +++ b/fs/xfs/xfs_aops.c @@ -24,6 +24,7 @@ #include "xfs_zone_alloc.h" #include "xfs_rtgroup.h" #include "xfs_fsverity.h" +#include struct xfs_writepage_ctx { struct iomap_writepage_ctx ctx; @@ -607,7 +608,7 @@ xfs_bio_submit_read( { xfs_ioend_submit_read(iter->inode, ctx->read_ctx, ctx->read_ctx_file_offset, - iomap_ioend_flags(&iter->iomap)); + iomap_ioend_flags(&iter->iomap), ctx->vi); ctx->read_ctx = NULL; } @@ -619,11 +620,13 @@ static const struct iomap_read_ops xfs_iomap_read_ops = { static inline const struct iomap_read_ops * xfs_get_iomap_read_ops( - const struct address_space *mapping) + const struct address_space *mapping, + loff_t position) { struct xfs_inode *ip = XFS_I(mapping->host); - if (bdev_has_integrity_csum(xfs_inode_buftarg(ip)->bt_bdev)) + if (bdev_has_integrity_csum(xfs_inode_buftarg(ip)->bt_bdev) || + xfs_fsverity_is_file_data(ip, position)) return &xfs_iomap_read_ops; return &iomap_bio_read_ops; } @@ -635,7 +638,7 @@ xfs_vm_read_folio( { struct iomap_read_folio_ctx ctx = { .cur_folio = folio }; - ctx.ops = xfs_get_iomap_read_ops(folio->mapping); + ctx.ops = xfs_get_iomap_read_ops(folio->mapping, folio_pos(folio)); iomap_read_folio(&xfs_read_iomap_ops, &ctx, NULL); return 0; } @@ -646,7 +649,7 @@ xfs_vm_readahead( { struct iomap_read_folio_ctx ctx = { .rac = rac }; - ctx.ops = xfs_get_iomap_read_ops(rac->mapping), + ctx.ops = xfs_get_iomap_read_ops(rac->mapping, readahead_pos(rac)); iomap_readahead(&xfs_read_iomap_ops, &ctx, NULL); } diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c index 67c1357f4701..e9927688086d 100644 --- a/fs/xfs/xfs_file.c +++ b/fs/xfs/xfs_file.c @@ -237,7 +237,8 @@ xfs_dio_read_bounce_submit_io( loff_t file_offset) { xfs_ioend_submit_read(iter->inode, bio, file_offset, - iomap_ioend_flags(&iter->iomap) | IOMAP_IOEND_DIRECT); + iomap_ioend_flags(&iter->iomap) | IOMAP_IOEND_DIRECT, + NULL); } static const struct iomap_dio_ops xfs_dio_read_bounce_ops = { diff --git a/fs/xfs/xfs_fsverity.c b/fs/xfs/xfs_fsverity.c index d86009629b56..d1b3ccc65322 100644 --- a/fs/xfs/xfs_fsverity.c +++ b/fs/xfs/xfs_fsverity.c @@ -20,3 +20,12 @@ xfs_fsverity_metadata_offset( { return round_up(i_size_read(VFS_IC(ip)), XFS_FSVERITY_START_ALIGN); } + +bool +xfs_fsverity_is_file_data( + const struct xfs_inode *ip, + loff_t offset) +{ + return fsverity_active(VFS_IC(ip)) && + offset < xfs_fsverity_metadata_offset(ip); +} diff --git a/fs/xfs/xfs_fsverity.h b/fs/xfs/xfs_fsverity.h index 5771db2cd797..ec77ba571106 100644 --- a/fs/xfs/xfs_fsverity.h +++ b/fs/xfs/xfs_fsverity.h @@ -9,12 +9,18 @@ #ifdef CONFIG_FS_VERITY loff_t xfs_fsverity_metadata_offset(const struct xfs_inode *ip); +bool xfs_fsverity_is_file_data(const struct xfs_inode *ip, loff_t offset); #else static inline loff_t xfs_fsverity_metadata_offset(const struct xfs_inode *ip) { WARN_ON_ONCE(1); return ULLONG_MAX; } +static inline bool xfs_fsverity_is_file_data(const struct xfs_inode *ip, + loff_t offset) +{ + return false; +} #endif /* CONFIG_FS_VERITY */ #endif /* __XFS_FSVERITY_H__ */ diff --git a/fs/xfs/xfs_ioend.c b/fs/xfs/xfs_ioend.c index 641f0d881b07..b0370af7a0f7 100644 --- a/fs/xfs/xfs_ioend.c +++ b/fs/xfs/xfs_ioend.c @@ -18,7 +18,9 @@ #include "xfs_ioend.h" #include "xfs_error.h" #include "xfs_errortag.h" +#include "xfs_fsverity.h" #include +#include static void xfs_end_bio_bounced( @@ -87,6 +89,20 @@ xfs_read_bounce_and_resubmit( xfs_bounce_submit_ioend); } +static void +xfs_end_fsverity_io_read( + struct work_struct *work) +{ + struct iomap_ioend *ioend = + container_of(work, struct iomap_ioend, work); + + if (!ioend->io_bio.bi_status) + fsverity_verify_bio(ioend->io_vi, &ioend->io_bio); + + iomap_finish_ioends( + ioend, blk_status_to_errno(ioend->io_bio.bi_status)); +} + static void xfs_end_io_read( struct bio *bio) @@ -113,6 +129,26 @@ xfs_end_io_read( } } + /* + * If we don't have block device integrity (IOMAP_IOEND_INTEGRITY), + * there won't be any ioends containing fsverity metadata. This means + * that those won't get mixed with data ioends causing self-deadlock or + * rescuer thread deadlock. + * + * Without offloading the data ioend, verification can be done directly + * in this task context. + */ + if (IS_ENABLED(CONFIG_FS_VERITY) && !error && ioend->io_vi && + xfs_fsverity_is_file_data(ip, ioend->io_offset)) { + if (ioend->io_flags & IOMAP_IOEND_INTEGRITY) { + fsverity_enqueue_verify_work(&ioend->work); + return; + } + + fsverity_verify_bio(ioend->io_vi, &ioend->io_bio); + error = blk_status_to_errno(ioend->io_bio.bi_status); + } + iomap_finish_ioends(ioend, error); } @@ -121,13 +157,17 @@ xfs_ioend_submit_read( struct inode *inode, struct bio *bio, loff_t file_offset, - u16 ioend_flags) + u16 ioend_flags, + struct fsverity_info *vi) { struct xfs_inode *ip = XFS_I(inode); struct xfs_mount *mp = ip->i_mount; struct iomap_ioend *ioend; ioend = iomap_init_ioend(inode, bio, file_offset, ioend_flags); + ioend->io_vi = vi; + INIT_WORK(&ioend->work, xfs_end_fsverity_io_read); + if ((ioend_flags & IOMAP_IOEND_DIRECT) && READ_ONCE(mp->m_read_bounce) == XFS_READ_BOUNCE_ALWAYS) { iomap_bounce_read(ioend, bdev_logical_block_size(bio->bi_bdev), diff --git a/fs/xfs/xfs_ioend.h b/fs/xfs/xfs_ioend.h index 7c2a1ea3e6ed..992c248a693a 100644 --- a/fs/xfs/xfs_ioend.h +++ b/fs/xfs/xfs_ioend.h @@ -2,6 +2,8 @@ #ifndef __XFS_IOEND_H #define __XFS_IOEND_H +#include + /* * Fast and loose check if this write could update the on-disk inode size. */ @@ -13,6 +15,6 @@ static inline bool xfs_ioend_is_append(struct iomap_ioend *ioend) void xfs_end_bio(struct bio *bio); void xfs_ioend_submit_read(struct inode *inode, struct bio *bio, - loff_t file_offset, u16 ioend_flags); + loff_t file_offset, u16 ioend_flags, struct fsverity_info *vi); #endif /* __XFS_IOEND_H */ diff --git a/include/linux/iomap.h b/include/linux/iomap.h index f9e2fce21be0..96a00d61d4e8 100644 --- a/include/linux/iomap.h +++ b/include/linux/iomap.h @@ -455,6 +455,7 @@ struct iomap_ioend { sector_t io_sector; /* start sector of ioend */ void *io_private; /* file system private data */ struct fsverity_info *io_vi; /* fsverity info */ + struct work_struct work; /* fsverity blocking I/O */ struct bio io_bio; /* MUST BE LAST! */ }; -- 2.54.0