From: "Darrick J. Wong" <djwong@kernel.org>
To: aalbersh@redhat.com, ebiggers@kernel.org, cem@kernel.org,
djwong@kernel.org
Cc: linux-fsdevel@vger.kernel.org, linux-xfs@vger.kernel.org,
fsverity@lists.linux.dev
Subject: [PATCH 34/38] xfs_scrub: use MADV_POPULATE_READ to check verity files
Date: Mon, 29 Apr 2024 20:39:45 -0700 [thread overview]
Message-ID: <171444683629.960383.17431859183948881831.stgit@frogsfrogsfrogs> (raw)
In-Reply-To: <171444683053.960383.12871831441554683674.stgit@frogsfrogsfrogs>
From: Darrick J. Wong <djwong@kernel.org>
Use madvise to pull a large number of pages into the pagecache with a
single system call. For the common case that everything is consistent,
this amortizes syscall overhead over a large amount of data.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
---
scrub/phase6.c | 133 ++++++++++++++++++++++++++++++++++++++++++++++++--------
1 file changed, 115 insertions(+), 18 deletions(-)
diff --git a/scrub/phase6.c b/scrub/phase6.c
index 983470b7bece..7bb11510d332 100644
--- a/scrub/phase6.c
+++ b/scrub/phase6.c
@@ -25,6 +25,7 @@
#include "libfrog/bulkstat.h"
#include "descr.h"
#include "progress.h"
+#include <sys/mman.h>
/*
* Phase 6: Verify data file integrity.
@@ -759,6 +760,97 @@ record_verity_success(
*fail_len = 0;
}
+/* Map at most this many bytes at a time. */
+#define MMAP_LENGTH (4194304)
+
+/*
+ * Use MADV_POPULATE_READ to validate verity file contents. Returns @length if
+ * the entire region validated ok; 0 to signal to the caller that they should
+ * fall back to regular reads; or a negative errno if some other error
+ * happened.
+ */
+static ssize_t
+validate_mmap(
+ int fd,
+ off_t pos,
+ size_t length)
+{
+ void *addr;
+ int ret;
+
+ /*
+ * Try to map this file into the address space. If that fails, we can
+ * fall back to reading the file contents with read(), so collapse all
+ * error codes to EFAULT.
+ */
+ addr = mmap(NULL, length, PROT_READ, MAP_SHARED, fd, pos);
+ if (addr == MAP_FAILED)
+ return 0;
+
+ /* Returns EFAULT for read IO errors. */
+ ret = madvise(addr, length, MADV_POPULATE_READ);
+ if (ret) {
+ munmap(addr, length);
+ if (errno == EFAULT)
+ return 0;
+ return -errno;
+ }
+
+ ret = munmap(addr, length);
+ if (ret)
+ return -errno;
+
+ return length;
+}
+
+/*
+ * Use pread to validate verity file contents. Returns the number of bytes
+ * validated; 0 to signal to the caller that EOF was encountered; or a negative
+ * errno if some other error happened.
+ */
+static ssize_t
+validate_pread(
+ struct scrub_ctx *ctx,
+ struct descr *dsc,
+ int fd,
+ const struct stat *statbuf,
+ off_t pos,
+ size_t length,
+ off_t *fail_pos,
+ off_t *fail_len)
+{
+ ssize_t validated;
+
+ for (validated = 0;
+ validated < length;
+ validated += statbuf->st_blksize, pos += statbuf->st_blksize) {
+ char c;
+ ssize_t bytes_read;
+
+ bytes_read = pread(fd, &c, 1, pos);
+ if (!bytes_read)
+ break;
+ if (bytes_read > 0) {
+ record_verity_success(ctx, dsc, fail_pos, fail_len);
+ continue;
+ }
+
+ if (errno == EIO) {
+ size_t length = min(statbuf->st_size - pos,
+ statbuf->st_blksize);
+
+ record_verity_error(ctx, dsc, pos, length, fail_pos,
+ fail_len);
+ continue;
+ }
+
+ str_errno(ctx, descr_render(dsc));
+ return -errno;
+ }
+
+ return validated;
+}
+
/* Scan a verity file's data looking for validation errors. */
static void
scan_verity_file(
@@ -770,10 +862,15 @@ scan_verity_file(
struct verity_file_ctx *vf = arg;
struct scrub_ctx *ctx = vf->vc->ctx;
off_t pos;
+ off_t max_map_pos;
off_t fail_pos = -1, fail_len = 0;
int fd;
int ret;
DEFINE_DESCR(dsc, ctx, render_ino_from_handle);
+ static long pagesize;
+
+ if (!pagesize)
+ pagesize = sysconf(_SC_PAGESIZE);
descr_set(&dsc, &vf->handle);
@@ -818,30 +915,30 @@ scan_verity_file(
goto out_fd;
}
- /* Read a single byte from each block in the file to validate. */
- for (pos = 0; pos < sb.st_size; pos += sb.st_blksize) {
- char c;
- ssize_t bytes_read;
+ /* Validate the file contents with MADV_POPULATE_READ and pread */
+ max_map_pos = roundup(sb.st_size, pagesize);
+ for (pos = 0; pos < max_map_pos; pos += MMAP_LENGTH) {
+ size_t length = min(max_map_pos - pos, MMAP_LENGTH);
+ ssize_t validated;
- bytes_read = pread(fd, &c, 1, pos);
- if (!bytes_read)
- break;
- if (bytes_read > 0) {
+ validated = validate_mmap(fd, pos, length);
+ if (validated > 0) {
record_verity_success(ctx, &dsc, &fail_pos, &fail_len);
- progress_add(sb.st_blksize);
+ progress_add(validated);
continue;
}
-
- if (errno == EIO) {
- size_t length = min(sb.st_size - pos, sb.st_blksize);
-
- record_verity_error(ctx, &dsc, pos, length, &fail_pos,
- &fail_len);
- continue;
+ if (validated < 0) {
+ errno = -validated;
+ str_errno(ctx, descr_render(&dsc));
+ goto out_fd;
}
- str_errno(ctx, descr_render(&dsc));
- break;
+ validated = validate_pread(ctx, &dsc, fd, &sb, pos, length,
+ &fail_pos, &fail_len);
+ if (validated <= 0)
+ break;
+
+ progress_add(validated);
}
report_verity_error(ctx, &dsc, fail_pos, fail_len);
next prev parent reply other threads:[~2024-04-30 3:39 UTC|newest]
Thread overview: 165+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-04-30 3:11 [PATCHBOMB v5.6] fs-verity support for XFS Darrick J. Wong
2024-04-30 3:18 ` [PATCHSET v5.6 1/2] fs-verity: support merkle tree access by blocks Darrick J. Wong
2024-04-30 3:19 ` [PATCH 01/18] fs: add FS_XFLAG_VERITY for verity files Darrick J. Wong
2024-04-30 3:19 ` [PATCH 02/18] fsverity: pass tree_blocksize to end_enable_verity() Darrick J. Wong
2024-04-30 3:20 ` [PATCH 03/18] fsverity: convert verification to use byte instead of page offsets Darrick J. Wong
2024-05-01 7:33 ` Christoph Hellwig
2024-05-01 22:33 ` Darrick J. Wong
2024-05-02 0:42 ` Eric Biggers
2024-05-08 20:14 ` Darrick J. Wong
2024-04-30 3:20 ` [PATCH 04/18] fsverity: support block-based Merkle tree caching Darrick J. Wong
2024-05-01 7:36 ` Christoph Hellwig
2024-05-01 22:35 ` Darrick J. Wong
2024-05-02 4:42 ` Christoph Hellwig
2024-05-15 2:16 ` Eric Biggers
2024-04-30 3:20 ` [PATCH 05/18] fsverity: pass the merkle tree block level to fsverity_read_merkle_tree_block Darrick J. Wong
2024-04-30 3:20 ` [PATCH 06/18] fsverity: add per-sb workqueue for post read processing Darrick J. Wong
2024-04-30 3:21 ` [PATCH 07/18] fsverity: add tracepoints Darrick J. Wong
2024-04-30 3:21 ` [PATCH 08/18] fsverity: pass the new tree size and block size to ->begin_enable_verity Darrick J. Wong
2024-04-30 3:21 ` [PATCH 09/18] fsverity: expose merkle tree geometry to callers Darrick J. Wong
2024-04-30 3:22 ` [PATCH 10/18] fsverity: box up the write_merkle_tree_block parameters too Darrick J. Wong
2024-04-30 3:22 ` [PATCH 11/18] fsverity: pass the zero-hash value to the implementation Darrick J. Wong
2024-04-30 3:22 ` [PATCH 12/18] fsverity: report validation errors back to the filesystem Darrick J. Wong
2024-04-30 3:22 ` [PATCH 13/18] fsverity: pass super_block to fsverity_enqueue_verify_work Darrick J. Wong
2024-04-30 3:23 ` [PATCH 14/18] ext4: use a per-superblock fsverity workqueue Darrick J. Wong
2024-04-30 3:23 ` [PATCH 15/18] f2fs: " Darrick J. Wong
2024-04-30 3:23 ` [PATCH 16/18] btrfs: " Darrick J. Wong
2024-04-30 3:23 ` [PATCH 17/18] fsverity: remove system-wide workqueue Darrick J. Wong
2024-04-30 3:24 ` [PATCH 18/18] iomap: integrate fs-verity verification into iomap's read path Darrick J. Wong
2024-05-01 7:10 ` Christoph Hellwig
2024-05-01 22:37 ` Darrick J. Wong
2024-04-30 3:18 ` [PATCHSET v5.6 2/2] xfs: fs-verity support Darrick J. Wong
2024-04-30 3:24 ` [PATCH 01/26] xfs: use unsigned ints for non-negative quantities in xfs_attr_remote.c Darrick J. Wong
2024-05-01 6:55 ` Christoph Hellwig
2024-05-01 22:39 ` Darrick J. Wong
2024-05-02 4:56 ` Christoph Hellwig
2024-05-02 5:56 ` Chandan Babu R
2024-05-02 6:34 ` Christoph Hellwig
2024-04-30 3:24 ` [PATCH 02/26] xfs: turn XFS_ATTR3_RMT_BUF_SPACE into a function Darrick J. Wong
2024-05-01 6:55 ` Christoph Hellwig
2024-04-30 3:24 ` [PATCH 03/26] xfs: create a helper to compute the blockcount of a max sized remote value Darrick J. Wong
2024-05-01 6:56 ` Christoph Hellwig
2024-04-30 3:25 ` [PATCH 04/26] xfs: minor cleanups of xfs_attr3_rmt_blocks Darrick J. Wong
2024-05-01 6:56 ` Christoph Hellwig
2024-04-30 3:25 ` [PATCH 05/26] xfs: use an empty transaction to protect xfs_attr_get from deadlocks Darrick J. Wong
2024-05-01 6:57 ` Christoph Hellwig
2024-05-01 22:42 ` Darrick J. Wong
2024-04-30 3:25 ` [PATCH 06/26] xfs: add attribute type for fs-verity Darrick J. Wong
2024-04-30 3:25 ` [PATCH 07/26] xfs: do not use xfs_attr3_rmt_hdr for remote verity value blocks Darrick J. Wong
2024-04-30 3:26 ` [PATCH 08/26] xfs: add fs-verity ro-compat flag Darrick J. Wong
2024-04-30 3:26 ` [PATCH 09/26] xfs: add inode on-disk VERITY flag Darrick J. Wong
2024-04-30 3:26 ` [PATCH 10/26] xfs: initialize fs-verity on file open and cleanup on inode destruction Darrick J. Wong
2024-04-30 3:26 ` [PATCH 11/26] xfs: don't allow to enable DAX on fs-verity sealed inode Darrick J. Wong
2024-04-30 3:27 ` [PATCH 12/26] xfs: disable direct read path for fs-verity files Darrick J. Wong
2024-04-30 3:27 ` [PATCH 13/26] xfs: widen flags argument to the xfs_iflags_* helpers Darrick J. Wong
2024-05-01 6:54 ` Christoph Hellwig
2024-05-01 22:44 ` Darrick J. Wong
2024-04-30 3:27 ` [PATCH 14/26] xfs: add fs-verity support Darrick J. Wong
2024-04-30 3:28 ` [PATCH 15/26] xfs: create a per-mount shrinker for verity inodes merkle tree blocks Darrick J. Wong
2024-04-30 3:28 ` [PATCH 16/26] xfs: shrink verity blob cache Darrick J. Wong
2024-04-30 3:28 ` [PATCH 17/26] xfs: don't store trailing zeroes of merkle tree blocks Darrick J. Wong
2024-04-30 3:28 ` [PATCH 18/26] xfs: use merkle tree offset as attr hash Darrick J. Wong
2024-05-01 6:53 ` Christoph Hellwig
2024-05-01 7:23 ` Christoph Hellwig
2024-05-07 21:24 ` Darrick J. Wong
2024-05-08 11:47 ` Christoph Hellwig
2024-05-08 20:26 ` Darrick J. Wong
2024-05-09 5:02 ` Christoph Hellwig
2024-05-09 20:02 ` Darrick J. Wong
2024-05-10 5:08 ` Christoph Hellwig
2024-05-10 6:20 ` Christoph Hellwig
2024-05-17 17:17 ` Darrick J. Wong
2024-05-20 12:39 ` Christoph Hellwig
2024-05-20 16:02 ` Darrick J. Wong
2024-05-22 14:37 ` Christoph Hellwig
2024-05-22 18:29 ` Eric Biggers
2024-05-31 21:28 ` Darrick J. Wong
2024-05-31 21:45 ` Eric Biggers
2024-05-09 17:46 ` Eric Biggers
2024-05-09 18:04 ` Darrick J. Wong
2024-05-09 18:36 ` Eric Biggers
2024-04-30 3:29 ` [PATCH 19/26] xfs: don't bother storing merkle tree blocks for zeroed data blocks Darrick J. Wong
2024-05-01 6:47 ` Christoph Hellwig
2024-05-01 22:47 ` Darrick J. Wong
2024-05-02 0:01 ` Eric Biggers
2024-05-08 20:26 ` Darrick J. Wong
2024-04-30 3:29 ` [PATCH 20/26] xfs: add fs-verity ioctls Darrick J. Wong
2024-04-30 3:29 ` [PATCH 21/26] xfs: advertise fs-verity being available on filesystem Darrick J. Wong
2024-04-30 3:29 ` [PATCH 22/26] xfs: check and repair the verity inode flag state Darrick J. Wong
2024-04-30 3:30 ` [PATCH 23/26] xfs: teach online repair to evaluate fsverity xattrs Darrick J. Wong
2024-04-30 3:30 ` [PATCH 24/26] xfs: report verity failures through the health system Darrick J. Wong
2024-04-30 3:30 ` [PATCH 25/26] xfs: make it possible to disable fsverity Darrick J. Wong
2024-05-01 6:48 ` Christoph Hellwig
2024-05-01 22:50 ` Darrick J. Wong
2024-05-02 0:15 ` Eric Biggers
2024-05-08 20:31 ` Darrick J. Wong
2024-05-09 5:04 ` Christoph Hellwig
2024-05-09 14:45 ` Darrick J. Wong
2024-05-09 15:06 ` Christoph Hellwig
2024-05-09 15:09 ` Darrick J. Wong
2024-05-09 15:13 ` Christoph Hellwig
2024-05-09 15:43 ` Darrick J. Wong
2024-05-17 19:36 ` Theodore Ts'o
2024-04-30 3:30 ` [PATCH 26/26] xfs: enable ro-compat fs-verity flag Darrick J. Wong
2024-04-30 3:19 ` [PATCHSET v5.6] xfsprogs: fs-verity support for XFS Darrick J. Wong
2024-04-30 3:31 ` [PATCH 01/38] fs: add FS_XFLAG_VERITY for verity files Darrick J. Wong
2024-04-30 3:31 ` [PATCH 02/38] xfs: use unsigned ints for non-negative quantities in xfs_attr_remote.c Darrick J. Wong
2024-04-30 3:31 ` [PATCH 03/38] xfs: turn XFS_ATTR3_RMT_BUF_SPACE into a function Darrick J. Wong
2024-04-30 3:31 ` [PATCH 04/38] xfs: create a helper to compute the blockcount of a max sized remote value Darrick J. Wong
2024-04-30 3:32 ` [PATCH 05/38] xfs: minor cleanups of xfs_attr3_rmt_blocks Darrick J. Wong
2024-04-30 3:32 ` [PATCH 06/38] xfs: use an empty transaction to protect xfs_attr_get from deadlocks Darrick J. Wong
2024-04-30 3:32 ` [PATCH 07/38] xfs: add attribute type for fs-verity Darrick J. Wong
2024-04-30 3:32 ` [PATCH 08/38] xfs: do not use xfs_attr3_rmt_hdr for remote verity value blocks Darrick J. Wong
2024-04-30 3:33 ` [PATCH 09/38] xfs: add fs-verity ro-compat flag Darrick J. Wong
2024-04-30 3:33 ` [PATCH 10/38] xfs: add inode on-disk VERITY flag Darrick J. Wong
2024-04-30 3:33 ` [PATCH 11/38] xfs: add fs-verity support Darrick J. Wong
2024-04-30 3:34 ` [PATCH 12/38] xfs: use merkle tree offset as attr hash Darrick J. Wong
2024-04-30 3:34 ` [PATCH 13/38] xfs: advertise fs-verity being available on filesystem Darrick J. Wong
2024-04-30 3:34 ` [PATCH 14/38] xfs: report verity failures through the health system Darrick J. Wong
2024-04-30 3:34 ` [PATCH 15/38] xfs: enable ro-compat fs-verity flag Darrick J. Wong
2024-04-30 3:35 ` [PATCH 16/38] libfrog: add fsverity to xfs_report_geom output Darrick J. Wong
2024-04-30 3:35 ` [PATCH 17/38] xfs_db: introduce attr_modify command Darrick J. Wong
2024-04-30 3:35 ` [PATCH 18/38] xfs_db: add ATTR_PARENT support to " Darrick J. Wong
2024-04-30 3:35 ` [PATCH 19/38] xfs_db: make attr_set/remove/modify be able to handle fs-verity attrs Darrick J. Wong
2024-04-30 3:36 ` [PATCH 20/38] man: document attr_modify command Darrick J. Wong
2024-04-30 3:36 ` [PATCH 21/38] xfs_db: create hex string as a field type Darrick J. Wong
2024-04-30 3:36 ` [PATCH 22/38] xfs_db: dump verity features and metadata Darrick J. Wong
2024-04-30 3:36 ` [PATCH 23/38] xfs_db: dump merkle tree data Darrick J. Wong
2024-04-30 3:37 ` [PATCH 24/38] xfs_db: dump the verity descriptor Darrick J. Wong
2024-04-30 3:37 ` [PATCH 25/38] xfs_db: don't obfuscate verity xattrs Darrick J. Wong
2024-04-30 3:37 ` [PATCH 26/38] xfs_db: dump the inode verity flag Darrick J. Wong
2024-04-30 3:37 ` [PATCH 27/38] xfs_db: compute hashes of merkle tree blocks Darrick J. Wong
2024-04-30 3:38 ` [PATCH 28/38] xfs_repair: junk fsverity xattrs when unnecessary Darrick J. Wong
2024-04-30 3:38 ` [PATCH 29/38] xfs_repair: clear verity iflag when verity isn't supported Darrick J. Wong
2024-04-30 3:38 ` [PATCH 30/38] xfs_repair: handle verity remote attrs Darrick J. Wong
2024-04-30 3:38 ` [PATCH 31/38] xfs_repair: allow upgrading filesystems with verity Darrick J. Wong
2024-04-30 3:39 ` [PATCH 32/38] xfs_scrub: check verity file metadata Darrick J. Wong
2024-04-30 3:39 ` [PATCH 33/38] xfs_scrub: validate verity file contents when doing a media scan Darrick J. Wong
2024-04-30 3:39 ` Darrick J. Wong [this message]
2024-04-30 3:40 ` [PATCH 35/38] xfs_spaceman: report data corruption Darrick J. Wong
2024-04-30 3:40 ` [PATCH 36/38] xfs_io: report fsverity status via statx Darrick J. Wong
2024-04-30 3:40 ` [PATCH 37/38] xfs_io: create magic command to disable verity Darrick J. Wong
2024-04-30 3:40 ` [PATCH 38/38] mkfs.xfs: add verity parameter Darrick J. Wong
2024-04-30 3:19 ` [PATCHSET v5.6] fstests: fs-verity support for XFS Darrick J. Wong
2024-04-30 3:41 ` [PATCH 1/6] common/verity: enable fsverity " Darrick J. Wong
2024-04-30 12:39 ` Andrey Albershteyn
2024-04-30 15:35 ` Darrick J. Wong
2024-04-30 3:41 ` [PATCH 2/6] xfs/{021,122}: adapt to fsverity xattrs Darrick J. Wong
2024-04-30 12:46 ` Andrey Albershteyn
2024-04-30 15:36 ` Darrick J. Wong
2024-04-30 3:41 ` [PATCH 3/6] xfs/122: adapt to fsverity Darrick J. Wong
2024-04-30 12:45 ` Andrey Albershteyn
2024-04-30 15:37 ` Darrick J. Wong
2024-04-30 3:41 ` [PATCH 4/6] xfs: test xfs_scrub detection and correction of corrupt fsverity metadata Darrick J. Wong
2024-04-30 12:29 ` Andrey Albershteyn
2024-04-30 15:43 ` Darrick J. Wong
2024-04-30 3:42 ` [PATCH 5/6] xfs: test disabling fsverity Darrick J. Wong
2024-04-30 12:56 ` Andrey Albershteyn
2024-04-30 13:11 ` Andrey Albershteyn
2024-04-30 15:48 ` Darrick J. Wong
2024-04-30 18:06 ` Andrey Albershteyn
2024-04-30 3:42 ` [PATCH 6/6] common/populate: add verity files to populate xfs images Darrick J. Wong
2024-04-30 13:22 ` Andrey Albershteyn
2024-04-30 15:49 ` Darrick J. Wong
2024-05-11 5:01 ` [PATCHSET v5.6] fstests: fs-verity support for XFS Zorro Lang
2024-05-17 15:56 ` Darrick J. Wong
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