diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-06-15 03:46:54 +0530 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-06-15 03:46:54 +0530 |
| commit | ec5d1ae94e99d8831427d00973da5620c7fb4368 (patch) | |
| tree | 9c2bd793eef39f6a56cd8c8c913818bb4dcc023c | |
| parent | 5b7c3f0fe36d8e867288f8e452ede82d178c757a (diff) | |
| parent | b7bae6880e8de2a5f693c18d87ad5cc26f157eb2 (diff) | |
| download | linux-next-ec5d1ae94e99d8831427d00973da5620c7fb4368.tar.gz linux-next-ec5d1ae94e99d8831427d00973da5620c7fb4368.zip | |
Merge tag 'vfs-7.2-rc1.iomap' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull iomap updates from Christian Brauner:
- Add the vfs infrastructure required to implement fs-verity support
for XFS with a post-EOF merkle tree: fsverity generates and stores a
zero-block hash, and iomap learns to verify data on buffered reads,
to handle fsverity during writeback via the new IOMAP_F_FSVERITY
flag, and to write fsverity metadata through iomap_fsverity_write().
- Skip the memset of the iomap in iomap_iter() once the iteration is
done. In high-IOPS scenarios (4k randread NVMe polling via io_uring)
the pointless memset wasted memory write bandwidth; this improves
IOPS by about 5% on ext4 and xfs.
- Add balance_dirty_pages_ratelimited() to iomap_zero_iter(), aligning
it with iomap_write_iter(). This prepares for the exFAT iomap
conversion where zeroing beyond valid_size can trigger large-scale
zeroing operations that caused memory pressure without throttling.
- Remove the over-strict inline data boundary check. If a filesystem
provides a valid inline_data pointer and length there is no reason to
require that inline data must not cross a page boundary.
- Don't make REQ_POLLED imply REQ_NOWAIT, matching the earlier
equivalent block layer fix: there are valid cases to poll for I/O
completion without REQ_NOWAIT, and REQ_NOWAIT for file system writes
is currently not supported as writes aren't idempotent.
- Introduce IOMAP_F_ZERO_TAIL for filesystems that maintain a separate
valid data length (exFAT, NTFS). For a write starting at or beyond
valid_size, __iomap_write_begin() now zeroes only the tail portion of
the block while preserving valid data before it, instead of leaving
stale data in the page cache. The flag is also added to the iomap
trace event strings.
* tag 'vfs-7.2-rc1.iomap' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
iomap: Add IOMAP_F_ZERO_TAIL flag to trace event strings
iomap: introduce iomap_fsverity_write() for writing fsverity metadata
iomap: teach iomap to read files with fsverity
iomap: introduce IOMAP_F_FSVERITY and teach writeback to handle fsverity
fsverity: generate and store zero-block hash
iomap: introduce IOMAP_F_ZERO_TAIL flag
iomap: don't make REQ_POLLED imply REQ_NOWAIT
iomap: remove over-strict inline data boundary check
iomap: add dirty page control to iomap_zero_iter
iomap: avoid memset iomap when iter is done
| -rw-r--r-- | fs/iomap/buffered-io.c | 116 | ||||
| -rw-r--r-- | fs/iomap/direct-io.c | 5 | ||||
| -rw-r--r-- | fs/iomap/ioend.c | 1 | ||||
| -rw-r--r-- | fs/iomap/iter.c | 12 | ||||
| -rw-r--r-- | fs/iomap/trace.h | 4 | ||||
| -rw-r--r-- | fs/verity/fsverity_private.h | 3 | ||||
| -rw-r--r-- | fs/verity/measure.c | 4 | ||||
| -rw-r--r-- | fs/verity/open.c | 3 | ||||
| -rw-r--r-- | fs/verity/pagecache.c | 22 | ||||
| -rw-r--r-- | include/linux/bio.h | 14 | ||||
| -rw-r--r-- | include/linux/fsverity.h | 8 | ||||
| -rw-r--r-- | include/linux/iomap.h | 27 |
12 files changed, 170 insertions, 49 deletions
diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c index d55b936e6986..5a107d59ae27 100644 --- a/fs/iomap/buffered-io.c +++ b/fs/iomap/buffered-io.c @@ -9,6 +9,7 @@ #include <linux/swap.h> #include <linux/migrate.h> #include <linux/fserror.h> +#include <linux/fsverity.h> #include "internal.h" #include "trace.h" @@ -353,9 +354,26 @@ static inline bool iomap_block_needs_zeroing(const struct iomap_iter *iter, { const struct iomap *srcmap = iomap_iter_srcmap(iter); - return srcmap->type != IOMAP_MAPPED || - (srcmap->flags & IOMAP_F_NEW) || - pos >= i_size_read(iter->inode); + /* + * If this block has not been written, there's nothing to read + */ + if (srcmap->type != IOMAP_MAPPED) + return true; + + /* + * Newly allocated blocks have not been written + */ + if (srcmap->flags & IOMAP_F_NEW) + return true; + + /* + * fsverity metadata is stored past i_size, we need to read it instead + * of zeroing + */ + if (srcmap->flags & IOMAP_F_FSVERITY) + return false; + + return pos >= i_size_read(iter->inode); } /** @@ -544,9 +562,27 @@ static int iomap_read_folio_iter(struct iomap_iter *iter, if (plen == 0) return 0; - /* zero post-eof blocks as the page may be mapped */ - if (iomap_block_needs_zeroing(iter, pos)) { + /* + * Handling of fsverity "holes". We hit this for two case: + * 1. No need to go further, the hole after fsverity + * descriptor is the end of the fsverity metadata. + * + * 2. This folio contains merkle tree blocks which need to be + * synthesized. If we already have fsverity info (ctx->vi) + * synthesize these blocks. + */ + if ((iomap->flags & IOMAP_F_FSVERITY) && + iomap->type == IOMAP_HOLE) { + if (ctx->vi) + fsverity_fill_zerohash(folio, poff, plen, + ctx->vi); + iomap_set_range_uptodate(folio, poff, plen); + } else if (iomap_block_needs_zeroing(iter, pos)) { + /* zero post-eof blocks as the page may be mapped */ folio_zero_range(folio, poff, plen); + if (ctx->vi && + !fsverity_verify_blocks(ctx->vi, folio, plen, poff)) + return -EIO; iomap_set_range_uptodate(folio, poff, plen); } else { if (!*bytes_submitted) @@ -597,6 +633,15 @@ void iomap_read_folio(const struct iomap_ops *ops, trace_iomap_readpage(iter.inode, 1); + /* + * Fetch fsverity_info for both data and fsverity metadata, as iomap + * needs zeroed hash for merkle tree block synthesis + */ + ctx->vi = fsverity_get_info(iter.inode); + if (ctx->vi && iter.pos < i_size_read(iter.inode)) + fsverity_readahead(ctx->vi, folio->index, + folio_nr_pages(folio)); + while ((ret = iomap_iter(&iter, ops)) > 0) iter.status = iomap_read_folio_iter(&iter, ctx, &bytes_submitted); @@ -664,6 +709,15 @@ void iomap_readahead(const struct iomap_ops *ops, trace_iomap_readahead(rac->mapping->host, readahead_count(rac)); + /* + * Fetch fsverity_info for both data and fsverity metadata, as iomap + * needs zeroed hash for merkle tree block synthesis + */ + ctx->vi = fsverity_get_info(iter.inode); + if (ctx->vi && iter.pos < i_size_read(iter.inode)) + fsverity_readahead(ctx->vi, readahead_index(rac), + readahead_count(rac)); + while (iomap_iter(&iter, ops) > 0) iter.status = iomap_readahead_iter(&iter, ctx, &cur_bytes_submitted); @@ -836,6 +890,7 @@ static int __iomap_write_begin(const struct iomap_iter *iter, return -EIO; folio_zero_segments(folio, poff, from, to, poff + plen); } else { + const struct iomap *iomap = iomap_iter_srcmap(iter); int status; if (iter->flags & IOMAP_NOWAIT) @@ -853,6 +908,9 @@ static int __iomap_write_begin(const struct iomap_iter *iter, len, status, GFP_NOFS); if (status) return status; + + if (iomap->flags & IOMAP_F_ZERO_TAIL) + folio_zero_segment(folio, to, poff + plen); } iomap_set_range_uptodate(folio, poff, plen); } while ((block_start += plen) < block_end); @@ -1058,7 +1116,6 @@ static bool iomap_write_end_inline(const struct iomap_iter *iter, void *addr; WARN_ON_ONCE(!folio_test_uptodate(folio)); - BUG_ON(!iomap_inline_data_valid(iomap)); if (WARN_ON_ONCE(!iomap->inline_data)) return false; @@ -1167,13 +1224,14 @@ retry: * unlock and release the folio. */ old_size = iter->inode->i_size; - if (pos + written > old_size) { + if (pos + written > old_size && + !(iter->iomap.flags & IOMAP_F_FSVERITY)) { i_size_write(iter->inode, pos + written); iter->iomap.flags |= IOMAP_F_SIZE_CHANGED; } __iomap_put_folio(iter, write_ops, written, folio); - if (old_size < pos) + if (old_size < pos && !(iter->iomap.flags & IOMAP_F_FSVERITY)) pagecache_isize_extended(iter->inode, old_size, pos); cond_resched(); @@ -1232,6 +1290,31 @@ iomap_file_buffered_write(struct kiocb *iocb, struct iov_iter *i, } EXPORT_SYMBOL_GPL(iomap_file_buffered_write); +int iomap_fsverity_write(struct file *file, loff_t pos, size_t length, + const void *buf, const struct iomap_ops *ops, + const struct iomap_write_ops *write_ops) +{ + int ret; + struct iov_iter iiter; + struct kvec kvec = { + .iov_base = (void *)buf, + .iov_len = length, + }; + struct kiocb iocb = { + .ki_filp = file, + .ki_ioprio = get_current_ioprio(), + .ki_pos = pos, + }; + + iov_iter_kvec(&iiter, WRITE, &kvec, 1, length); + + ret = iomap_file_buffered_write(&iocb, &iiter, ops, write_ops, NULL); + if (ret < 0) + return ret; + return ret == length ? 0 : -EIO; +} +EXPORT_SYMBOL_GPL(iomap_fsverity_write); + static void iomap_write_delalloc_ifs_punch(struct inode *inode, struct folio *folio, loff_t start_byte, loff_t end_byte, struct iomap *iomap, iomap_punch_t punch) @@ -1543,6 +1626,8 @@ static int iomap_zero_iter(struct iomap_iter *iter, bool *did_zero, size_t offset; bool ret; + balance_dirty_pages_ratelimited(iter->inode->i_mapping); + bytes = min_t(u64, SIZE_MAX, bytes); status = iomap_write_begin(iter, write_ops, &folio, &offset, &bytes); @@ -1797,13 +1882,20 @@ static int iomap_writeback_range(struct iomap_writepage_ctx *wpc, * Check interaction of the folio with the file end. * * If the folio is entirely beyond i_size, return false. If it straddles - * i_size, adjust end_pos and zero all data beyond i_size. + * i_size, adjust end_pos and zero all data beyond i_size. Don't skip fsverity + * folios as those are beyond i_size. */ -static bool iomap_writeback_handle_eof(struct folio *folio, struct inode *inode, - u64 *end_pos) +static bool iomap_writeback_handle_eof(struct folio *folio, + struct iomap_writepage_ctx *wpc, u64 *end_pos) { + struct inode *inode = wpc->inode; u64 isize = i_size_read(inode); + if (wpc->iomap.flags & IOMAP_F_FSVERITY) { + WARN_ON_ONCE(folio_pos(folio) < isize); + return true; + } + if (*end_pos > isize) { size_t poff = offset_in_folio(folio, isize); pgoff_t end_index = isize >> PAGE_SHIFT; @@ -1869,7 +1961,7 @@ int iomap_writeback_folio(struct iomap_writepage_ctx *wpc, struct folio *folio) trace_iomap_writeback_folio(inode, pos, folio_size(folio)); - if (!iomap_writeback_handle_eof(folio, inode, &end_pos)) + if (!iomap_writeback_handle_eof(folio, wpc, &end_pos)) return 0; WARN_ON_ONCE(end_pos <= pos); diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c index b36ee619cdcd..b485e3b191da 100644 --- a/fs/iomap/direct-io.c +++ b/fs/iomap/direct-io.c @@ -69,7 +69,7 @@ static void iomap_dio_submit_bio(const struct iomap_iter *iter, /* Sync dio can't be polled reliably */ if ((iocb->ki_flags & IOCB_HIPRI) && !is_sync_kiocb(iocb)) { - bio_set_polled(bio, iocb); + bio->bi_opf |= REQ_POLLED; WRITE_ONCE(iocb->private, bio); } @@ -603,9 +603,6 @@ static int iomap_dio_inline_iter(struct iomap_iter *iomi, struct iomap_dio *dio) if (WARN_ON_ONCE(!inline_data)) return -EIO; - if (WARN_ON_ONCE(!iomap_inline_data_valid(iomap))) - return -EIO; - if (dio->flags & IOMAP_DIO_WRITE) { loff_t size = iomi->inode->i_size; diff --git a/fs/iomap/ioend.c b/fs/iomap/ioend.c index acf3cf98b23a..f7c3e0c70fd7 100644 --- a/fs/iomap/ioend.c +++ b/fs/iomap/ioend.c @@ -28,6 +28,7 @@ struct iomap_ioend *iomap_init_ioend(struct inode *inode, ioend->io_offset = file_offset; ioend->io_size = bio->bi_iter.bi_size; ioend->io_sector = bio->bi_iter.bi_sector; + ioend->io_vi = NULL; ioend->io_private = NULL; return ioend; } diff --git a/fs/iomap/iter.c b/fs/iomap/iter.c index c04796f6e57f..e4a29829591a 100644 --- a/fs/iomap/iter.c +++ b/fs/iomap/iter.c @@ -6,17 +6,13 @@ #include <linux/iomap.h> #include "trace.h" -static inline void iomap_iter_reset_iomap(struct iomap_iter *iter) +static inline void iomap_iter_clean_fbatch(struct iomap_iter *iter) { if (iter->iomap.flags & IOMAP_F_FOLIO_BATCH) { folio_batch_release(iter->fbatch); folio_batch_reinit(iter->fbatch); iter->iomap.flags &= ~IOMAP_F_FOLIO_BATCH; } - - iter->status = 0; - memset(&iter->iomap, 0, sizeof(iter->iomap)); - memset(&iter->srcmap, 0, sizeof(iter->srcmap)); } /* Advance the current iterator position and decrement the remaining length */ @@ -102,10 +98,14 @@ int iomap_iter(struct iomap_iter *iter, const struct iomap_ops *ops) ret = 0; else ret = 1; - iomap_iter_reset_iomap(iter); + iomap_iter_clean_fbatch(iter); + iter->status = 0; if (ret <= 0) return ret; + memset(&iter->iomap, 0, sizeof(iter->iomap)); + memset(&iter->srcmap, 0, sizeof(iter->srcmap)); + begin: ret = ops->iomap_begin(iter->inode, iter->pos, iter->len, iter->flags, &iter->iomap, &iter->srcmap); diff --git a/fs/iomap/trace.h b/fs/iomap/trace.h index 097773c6db80..e1ea8392cf47 100644 --- a/fs/iomap/trace.h +++ b/fs/iomap/trace.h @@ -118,7 +118,9 @@ DEFINE_RANGE_EVENT(iomap_zero_iter); { IOMAP_F_ATOMIC_BIO, "ATOMIC_BIO" }, \ { IOMAP_F_PRIVATE, "PRIVATE" }, \ { IOMAP_F_SIZE_CHANGED, "SIZE_CHANGED" }, \ - { IOMAP_F_STALE, "STALE" } + { IOMAP_F_STALE, "STALE" }, \ + { IOMAP_F_FSVERITY, "FSVERITY" }, \ + { IOMAP_F_ZERO_TAIL, "ZERO TAIL" } #define IOMAP_DIO_STRINGS \ diff --git a/fs/verity/fsverity_private.h b/fs/verity/fsverity_private.h index 6e6854c19078..881d46f25e08 100644 --- a/fs/verity/fsverity_private.h +++ b/fs/verity/fsverity_private.h @@ -53,6 +53,9 @@ struct merkle_tree_params { u64 tree_size; /* Merkle tree size in bytes */ unsigned long tree_pages; /* Merkle tree size in pages */ + /* the hash of an all-zeroes block */ + u8 zero_digest[FS_VERITY_MAX_DIGEST_SIZE]; + /* * Starting block index for each tree level, ordered from leaf level (0) * to root level ('num_levels - 1') diff --git a/fs/verity/measure.c b/fs/verity/measure.c index 6a35623ebdf0..818083507885 100644 --- a/fs/verity/measure.c +++ b/fs/verity/measure.c @@ -68,8 +68,8 @@ EXPORT_SYMBOL_GPL(fsverity_ioctl_measure); * @alg: (out) the digest's algorithm, as a FS_VERITY_HASH_ALG_* value * @halg: (out) the digest's algorithm, as a HASH_ALGO_* value * - * Retrieves the fsverity digest of the given file. The file must have been - * opened at least once since the inode was last loaded into the inode cache; + * Retrieves the fsverity digest of the given file. The + * fsverity_ensure_verity_info() must be called on the inode beforehand; * otherwise this function will not recognize when fsverity is enabled. * * The file's fsverity digest consists of @raw_digest in combination with either diff --git a/fs/verity/open.c b/fs/verity/open.c index dfa0d1afe0fe..d0c56a7faa3b 100644 --- a/fs/verity/open.c +++ b/fs/verity/open.c @@ -153,6 +153,9 @@ int fsverity_init_merkle_tree_params(struct merkle_tree_params *params, goto out_err; } + fsverity_hash_block(params, page_address(ZERO_PAGE(0)), + params->zero_digest); + params->tree_size = offset << log_blocksize; params->tree_pages = PAGE_ALIGN(params->tree_size) >> PAGE_SHIFT; return 0; diff --git a/fs/verity/pagecache.c b/fs/verity/pagecache.c index 1819314ecaa3..99f5f53eea98 100644 --- a/fs/verity/pagecache.c +++ b/fs/verity/pagecache.c @@ -2,6 +2,7 @@ /* * Copyright 2019 Google LLC */ +#include "fsverity_private.h" #include <linux/export.h> #include <linux/fsverity.h> @@ -56,3 +57,24 @@ void generic_readahead_merkle_tree(struct inode *inode, pgoff_t index, folio_put(folio); } EXPORT_SYMBOL_GPL(generic_readahead_merkle_tree); + +/** + * fsverity_fill_zerohash() - fill folio with hashes of zero data block + * @folio: folio to fill + * @offset: offset in the folio to start + * @len: length of the range to fill with hashes + * @vi: fsverity info + */ +void fsverity_fill_zerohash(struct folio *folio, size_t offset, size_t len, + struct fsverity_info *vi) +{ + size_t off = offset; + + WARN_ON_ONCE(!IS_ALIGNED(offset, vi->tree_params.digest_size)); + WARN_ON_ONCE(!IS_ALIGNED(len, vi->tree_params.digest_size)); + + for (; off < (offset + len); off += vi->tree_params.digest_size) + memcpy_to_folio(folio, off, vi->tree_params.zero_digest, + vi->tree_params.digest_size); +} +EXPORT_SYMBOL_GPL(fsverity_fill_zerohash); diff --git a/include/linux/bio.h b/include/linux/bio.h index dc17780d6c1e..8300d5565e36 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -703,20 +703,6 @@ static inline bool bioset_initialized(struct bio_set *bs) return bs->bio_slab != NULL; } -/* - * Mark a bio as polled. Note that for async polled IO, the caller must - * expect -EWOULDBLOCK if we cannot allocate a request (or other resources). - * We cannot block waiting for requests on polled IO, as those completions - * must be found by the caller. This is different than IRQ driven IO, where - * it's safe to wait for IO to complete. - */ -static inline void bio_set_polled(struct bio *bio, struct kiocb *kiocb) -{ - bio->bi_opf |= REQ_POLLED; - if (kiocb->ki_flags & IOCB_NOWAIT) - bio->bi_opf |= REQ_NOWAIT; -} - static inline void bio_clear_polled(struct bio *bio) { bio->bi_opf &= ~REQ_POLLED; diff --git a/include/linux/fsverity.h b/include/linux/fsverity.h index a8f9aa75b792..6c467ded9751 100644 --- a/include/linux/fsverity.h +++ b/include/linux/fsverity.h @@ -201,6 +201,8 @@ bool fsverity_verify_blocks(struct fsverity_info *vi, struct folio *folio, size_t len, size_t offset); void fsverity_verify_bio(struct fsverity_info *vi, struct bio *bio); void fsverity_enqueue_verify_work(struct work_struct *work); +void fsverity_fill_zerohash(struct folio *folio, size_t offset, size_t len, + struct fsverity_info *vi); #else /* !CONFIG_FS_VERITY */ @@ -281,6 +283,12 @@ static inline void fsverity_enqueue_verify_work(struct work_struct *work) WARN_ON_ONCE(1); } +static inline void fsverity_fill_zerohash(struct folio *folio, size_t offset, + size_t len, struct fsverity_info *vi) +{ + WARN_ON_ONCE(1); +} + #endif /* !CONFIG_FS_VERITY */ static inline bool fsverity_verify_folio(struct fsverity_info *vi, diff --git a/include/linux/iomap.h b/include/linux/iomap.h index 2c5685adf3a9..3582ed1fe236 100644 --- a/include/linux/iomap.h +++ b/include/linux/iomap.h @@ -67,6 +67,9 @@ struct vm_fault; * bio, i.e. set REQ_ATOMIC. * * IOMAP_F_INTEGRITY indicates that the filesystems handles integrity metadata. + * + * IOMAP_F_ZERO_TAIL indicates the remainder of the block after the data + * written should be zeroed. */ #define IOMAP_F_NEW (1U << 0) #define IOMAP_F_DIRTY (1U << 1) @@ -86,6 +89,15 @@ struct vm_fault; #else #define IOMAP_F_INTEGRITY 0 #endif /* CONFIG_BLK_DEV_INTEGRITY */ +#define IOMAP_F_ZERO_TAIL (1U << 10) + +/* + * Indicates reads and writes of fsverity metadata. + * + * Fsverity metadata is stored after the regular file data and thus beyond + * i_size. + */ +#define IOMAP_F_FSVERITY (1U << 11) /* * Flag reserved for file system specific usage @@ -143,16 +155,6 @@ static inline void *iomap_inline_data(const struct iomap *iomap, loff_t pos) } /* - * Check if the mapping's length is within the valid range for inline data. - * This is used to guard against accessing data beyond the page inline_data - * points at. - */ -static inline bool iomap_inline_data_valid(const struct iomap *iomap) -{ - return iomap->length <= PAGE_SIZE - offset_in_page(iomap->inline_data); -} - -/* * When get_folio succeeds, put_folio will always be called to do any * cleanup work necessary. put_folio is responsible for unlocking and putting * @folio. @@ -351,6 +353,9 @@ static inline bool iomap_want_unshare_iter(const struct iomap_iter *iter) ssize_t iomap_file_buffered_write(struct kiocb *iocb, struct iov_iter *from, const struct iomap_ops *ops, const struct iomap_write_ops *write_ops, void *private); +int iomap_fsverity_write(struct file *file, loff_t pos, size_t length, + const void *buf, const struct iomap_ops *ops, + const struct iomap_write_ops *write_ops); void iomap_read_folio(const struct iomap_ops *ops, struct iomap_read_folio_ctx *ctx, void *private); void iomap_readahead(const struct iomap_ops *ops, @@ -427,6 +432,7 @@ struct iomap_ioend { loff_t io_offset; /* offset in the file */ sector_t io_sector; /* start sector of ioend */ void *io_private; /* file system private data */ + struct fsverity_info *io_vi; /* fsverity info */ struct bio io_bio; /* MUST BE LAST! */ }; @@ -501,6 +507,7 @@ struct iomap_read_folio_ctx { struct readahead_control *rac; void *read_ctx; loff_t read_ctx_file_offset; + struct fsverity_info *vi; }; struct iomap_read_ops { |
