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mirror of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2026-01-18 12:31:11 +00:00

2530 Commits

Author SHA1 Message Date
Linus Torvalds
a3fb8a61e4 A one-liner that leads to a startling (but also very much rational)
performance improvement in cases where an IMA policy with rules that
 are based on fsmagic matching is enforced, an encryption-related fixup
 that addresses generic/397 and other fstest failures and a couple of
 cleanups in CephFS.
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Merge tag 'ceph-for-6.16-rc1' of https://github.com/ceph/ceph-client

Pull ceph updates from Ilya Dryomov:

 - a one-liner that leads to a startling (but also very much rational)
   performance improvement in cases where an IMA policy with rules that
   are based on fsmagic matching is enforced

 - an encryption-related fixup that addresses generic/397 and other
   fstest failures

 - a couple of cleanups in CephFS

* tag 'ceph-for-6.16-rc1' of https://github.com/ceph/ceph-client:
  ceph: fix variable dereferenced before check in ceph_umount_begin()
  ceph: set superblock s_magic for IMA fsmagic matching
  ceph: cleanup hardcoded constants of file handle size
  ceph: fix possible integer overflow in ceph_zero_objects()
  ceph: avoid kernel BUG for encrypted inode with unaligned file size
2025-06-06 17:56:19 -07:00
Viacheslav Dubeyko
b828b4bf29 ceph: fix variable dereferenced before check in ceph_umount_begin()
smatch warnings:
fs/ceph/super.c:1042 ceph_umount_begin() warn: variable dereferenced before check 'fsc' (see line 1041)

vim +/fsc +1042 fs/ceph/super.c

void ceph_umount_begin(struct super_block *sb)
{
	struct ceph_fs_client *fsc = ceph_sb_to_fs_client(sb);

	doutc(fsc->client, "starting forced umount\n");
              ^^^^^^^^^^^
Dereferenced

	if (!fsc)
            ^^^^
Checked too late.

		return;
	fsc->mount_state = CEPH_MOUNT_SHUTDOWN;
	__ceph_umount_begin(fsc);
}

The VFS guarantees that the superblock is still
alive when it calls into ceph via ->umount_begin().
Finally, we don't need to check the fsc and
it should be valid. This patch simply removes
the fsc check.

Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/r/202503280852.YDB3pxUY-lkp@intel.com/
Signed-off-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Reviewed by: Alex Markuze <amarkuze@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2025-06-06 11:08:59 +02:00
Linus Torvalds
0fb34422b5 vfs-6.16-rc1.netfs
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Merge tag 'vfs-6.16-rc1.netfs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull netfs updates from Christian Brauner:

 - The main API document has been extensively updated/rewritten

 - Fix an oops in write-retry due to mis-resetting the I/O iterator

 - Fix the recording of transferred bytes for short DIO reads

 - Fix a request's work item to not require a reference, thereby
   avoiding the need to get rid of it in BH/IRQ context

 - Fix waiting and waking to be consistent about the waitqueue used

 - Remove NETFS_SREQ_SEEK_DATA_READ, NETFS_INVALID_WRITE,
   NETFS_ICTX_WRITETHROUGH, NETFS_READ_HOLE_CLEAR,
   NETFS_RREQ_DONT_UNLOCK_FOLIOS, and NETFS_RREQ_BLOCKED

 - Reorder structs to eliminate holes

 - Remove netfs_io_request::ractl

 - Only provide proc_link field if CONFIG_PROC_FS=y

 - Remove folio_queue::marks3

 - Fix undifferentiation of DIO reads from unbuffered reads

* tag 'vfs-6.16-rc1.netfs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  netfs: Fix undifferentiation of DIO reads from unbuffered reads
  netfs: Fix wait/wake to be consistent about the waitqueue used
  netfs: Fix the request's work item to not require a ref
  netfs: Fix setting of transferred bytes with short DIO reads
  netfs: Fix oops in write-retry from mis-resetting the subreq iterator
  fs/netfs: remove unused flag NETFS_RREQ_BLOCKED
  fs/netfs: remove unused flag NETFS_RREQ_DONT_UNLOCK_FOLIOS
  folio_queue: remove unused field `marks3`
  fs/netfs: declare field `proc_link` only if CONFIG_PROC_FS=y
  fs/netfs: remove `netfs_io_request.ractl`
  fs/netfs: reorder struct fields to eliminate holes
  fs/netfs: remove unused enum choice NETFS_READ_HOLE_CLEAR
  fs/netfs: remove unused flag NETFS_ICTX_WRITETHROUGH
  fs/netfs: remove unused source NETFS_INVALID_WRITE
  fs/netfs: remove unused flag NETFS_SREQ_SEEK_DATA_READ
2025-06-02 15:04:06 -07:00
Dennis Marttinen
72386d5245 ceph: set superblock s_magic for IMA fsmagic matching
The CephFS kernel driver forgets to set the filesystem magic signature in
its superblock. As a result, IMA policy rules based on fsmagic matching do
not apply as intended. This causes a major performance regression in Talos
Linux [1] when mounting CephFS volumes, such as when deploying Rook Ceph
[2]. Talos Linux ships a hardened kernel with the following IMA policy
(irrelevant lines omitted):

[...]
dont_measure fsmagic=0xc36400 # CEPH_SUPER_MAGIC
[...]
measure func=FILE_CHECK mask=^MAY_READ euid=0
measure func=FILE_CHECK mask=^MAY_READ uid=0
[...]

Currently, IMA compares 0xc36400 == 0x0 for CephFS files, resulting in all
files opened with O_RDONLY or O_RDWR getting measured with SHA512 on every
open(2):

10 69990c87e8af323d47e2d6ae4... ima-ng sha512:<hash> /data/cephfs/test-file

Since O_WRONLY is rare, this results in an order of magnitude lower
performance than expected for practically all file operations. Properly
setting CEPH_SUPER_MAGIC in the CephFS superblock resolves the regression.

Tests performed on a 3x replicated Ceph v19.3.0 cluster across three
i5-7200U nodes each equipped with one Micron 7400 MAX M.2 disk (BlueStore)
and Gigabit ethernet, on Talos Linux v1.10.2:

FS-Mark 3.3
Test: 500 Files, Empty
Files/s > Higher Is Better
6.12.27-talos . 16.6  |====
+twelho patch . 208.4 |====================================================

FS-Mark 3.3
Test: 500 Files, 1KB Size
Files/s > Higher Is Better
6.12.27-talos . 15.6  |=======
+twelho patch . 118.6 |====================================================

FS-Mark 3.3
Test: 500 Files, 32 Sub Dirs, 1MB Size
Files/s > Higher Is Better
6.12.27-talos . 12.7 |===============
+twelho patch . 44.7 |=====================================================

IO500 [3] 2fcd6d6 results (benchmarks within variance omitted):

| IO500 benchmark   | 6.12.27-talos  | +twelho patch  | Speedup   |
|-------------------|----------------|----------------|-----------|
| mdtest-easy-write | 0.018524 kIOPS | 1.135027 kIOPS | 6027.33 % |
| mdtest-hard-write | 0.018498 kIOPS | 0.973312 kIOPS | 5161.71 % |
| ior-easy-read     | 0.064727 GiB/s | 0.155324 GiB/s | 139.97 %  |
| mdtest-hard-read  | 0.018246 kIOPS | 0.780800 kIOPS | 4179.29 % |

This applies outside of synthetic benchmarks as well, for example, the time
to rsync a 55 MiB directory with ~12k of mostly small files drops from an
unusable 10m5s to a reasonable 26s (23x the throughput).

[1]: https://www.talos.dev/
[2]: https://www.talos.dev/v1.10/kubernetes-guides/configuration/ceph-with-rook/
[3]: https://github.com/IO500/io500

Cc: stable@vger.kernel.org
Signed-off-by: Dennis Marttinen <twelho@welho.tech>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2025-06-01 17:53:16 +02:00
Viacheslav Dubeyko
d50eb28f2d ceph: cleanup hardcoded constants of file handle size
The ceph/export.c contains very confusing logic of file handle size
calculation based on hardcoded values. This patch makes the cleanup of
this logic by means of introduction the named constants.

Signed-off-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Reviewed-by: Alex Markuze <amarkuze@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2025-06-01 17:53:16 +02:00
Dmitry Kandybka
0abd87942e ceph: fix possible integer overflow in ceph_zero_objects()
In 'ceph_zero_objects', promote 'object_size' to 'u64' to avoid possible
integer overflow.

Compile tested only.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Signed-off-by: Dmitry Kandybka <d.kandybka@gmail.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2025-06-01 17:53:16 +02:00
Viacheslav Dubeyko
060909278c ceph: avoid kernel BUG for encrypted inode with unaligned file size
The generic/397 test hits a BUG_ON for the case of encrypted inode with
unaligned file size (for example, 33K or 1K):

[ 877.737811] run fstests generic/397 at 2025-01-03 12:34:40
[ 877.875761] libceph: mon0 (2)127.0.0.1:40674 session established
[ 877.876130] libceph: client4614 fsid 19b90bca-f1ae-47a6-93dd-0b03ee637949
[ 877.991965] libceph: mon0 (2)127.0.0.1:40674 session established
[ 877.992334] libceph: client4617 fsid 19b90bca-f1ae-47a6-93dd-0b03ee637949
[ 878.017234] libceph: mon0 (2)127.0.0.1:40674 session established
[ 878.017594] libceph: client4620 fsid 19b90bca-f1ae-47a6-93dd-0b03ee637949
[ 878.031394] xfs_io (pid 18988) is setting deprecated v1 encryption policy; recommend upgrading to v2.
[ 878.054528] libceph: mon0 (2)127.0.0.1:40674 session established
[ 878.054892] libceph: client4623 fsid 19b90bca-f1ae-47a6-93dd-0b03ee637949
[ 878.070287] libceph: mon0 (2)127.0.0.1:40674 session established
[ 878.070704] libceph: client4626 fsid 19b90bca-f1ae-47a6-93dd-0b03ee637949
[ 878.264586] libceph: mon0 (2)127.0.0.1:40674 session established
[ 878.265258] libceph: client4629 fsid 19b90bca-f1ae-47a6-93dd-0b03ee637949
[ 878.374578] -----------[ cut here ]------------
[ 878.374586] kernel BUG at net/ceph/messenger.c:1070!
[ 878.375150] Oops: invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
[ 878.378145] CPU: 2 UID: 0 PID: 4759 Comm: kworker/2:9 Not tainted 6.13.0-rc5+ #1
[ 878.378969] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[ 878.380167] Workqueue: ceph-msgr ceph_con_workfn
[ 878.381639] RIP: 0010:ceph_msg_data_cursor_init+0x42/0x50
[ 878.382152] Code: 89 17 48 8b 46 70 55 48 89 47 08 c7 47 18 00 00 00 00 48 89 e5 e8 de cc ff ff 5d 31 c0 31 d2 31 f6 31 ff c3 cc cc cc cc 0f 0b <0f> 0b 0f 0b 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90
[ 878.383928] RSP: 0018:ffffb4ffc7cbbd28 EFLAGS: 00010287
[ 878.384447] RAX: ffffffff82bb9ac0 RBX: ffff981390c2f1f8 RCX: 0000000000000000
[ 878.385129] RDX: 0000000000009000 RSI: ffff981288232b58 RDI: ffff981390c2f378
[ 878.385839] RBP: ffffb4ffc7cbbe18 R08: 0000000000000000 R09: 0000000000000000
[ 878.386539] R10: 0000000000000000 R11: 0000000000000000 R12: ffff981390c2f030
[ 878.387203] R13: ffff981288232b58 R14: 0000000000000029 R15: 0000000000000001
[ 878.387877] FS: 0000000000000000(0000) GS:ffff9814b7900000(0000) knlGS:0000000000000000
[ 878.388663] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 878.389212] CR2: 00005e106a0554e0 CR3: 0000000112bf0001 CR4: 0000000000772ef0
[ 878.389921] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 878.390620] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 878.391307] PKRU: 55555554
[ 878.391567] Call Trace:
[ 878.391807] <TASK>
[ 878.392021] ? show_regs+0x71/0x90
[ 878.392391] ? die+0x38/0xa0
[ 878.392667] ? do_trap+0xdb/0x100
[ 878.392981] ? do_error_trap+0x75/0xb0
[ 878.393372] ? ceph_msg_data_cursor_init+0x42/0x50
[ 878.393842] ? exc_invalid_op+0x53/0x80
[ 878.394232] ? ceph_msg_data_cursor_init+0x42/0x50
[ 878.394694] ? asm_exc_invalid_op+0x1b/0x20
[ 878.395099] ? ceph_msg_data_cursor_init+0x42/0x50
[ 878.395583] ? ceph_con_v2_try_read+0xd16/0x2220
[ 878.396027] ? _raw_spin_unlock+0xe/0x40
[ 878.396428] ? raw_spin_rq_unlock+0x10/0x40
[ 878.396842] ? finish_task_switch.isra.0+0x97/0x310
[ 878.397338] ? __schedule+0x44b/0x16b0
[ 878.397738] ceph_con_workfn+0x326/0x750
[ 878.398121] process_one_work+0x188/0x3d0
[ 878.398522] ? __pfx_worker_thread+0x10/0x10
[ 878.398929] worker_thread+0x2b5/0x3c0
[ 878.399310] ? __pfx_worker_thread+0x10/0x10
[ 878.399727] kthread+0xe1/0x120
[ 878.400031] ? __pfx_kthread+0x10/0x10
[ 878.400431] ret_from_fork+0x43/0x70
[ 878.400771] ? __pfx_kthread+0x10/0x10
[ 878.401127] ret_from_fork_asm+0x1a/0x30
[ 878.401543] </TASK>
[ 878.401760] Modules linked in: hctr2 nhpoly1305_avx2 nhpoly1305_sse2 nhpoly1305 chacha_generic chacha_x86_64 libchacha adiantum libpoly1305 essiv authenc mptcp_diag xsk_diag tcp_diag udp_diag raw_diag inet_diag unix_diag af_packet_diag netlink_diag intel_rapl_msr intel_rapl_common intel_uncore_frequency_common skx_edac_common nfit kvm_intel kvm crct10dif_pclmul crc32_pclmul polyval_clmulni polyval_generic ghash_clmulni_intel sha256_ssse3 sha1_ssse3 aesni_intel joydev crypto_simd cryptd rapl input_leds psmouse sch_fq_codel serio_raw bochs i2c_piix4 floppy qemu_fw_cfg i2c_smbus mac_hid pata_acpi msr parport_pc ppdev lp parport efi_pstore ip_tables x_tables
[ 878.407319] ---[ end trace 0000000000000000 ]---
[ 878.407775] RIP: 0010:ceph_msg_data_cursor_init+0x42/0x50
[ 878.408317] Code: 89 17 48 8b 46 70 55 48 89 47 08 c7 47 18 00 00 00 00 48 89 e5 e8 de cc ff ff 5d 31 c0 31 d2 31 f6 31 ff c3 cc cc cc cc 0f 0b <0f> 0b 0f 0b 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90
[ 878.410087] RSP: 0018:ffffb4ffc7cbbd28 EFLAGS: 00010287
[ 878.410609] RAX: ffffffff82bb9ac0 RBX: ffff981390c2f1f8 RCX: 0000000000000000
[ 878.411318] RDX: 0000000000009000 RSI: ffff981288232b58 RDI: ffff981390c2f378
[ 878.412014] RBP: ffffb4ffc7cbbe18 R08: 0000000000000000 R09: 0000000000000000
[ 878.412735] R10: 0000000000000000 R11: 0000000000000000 R12: ffff981390c2f030
[ 878.413438] R13: ffff981288232b58 R14: 0000000000000029 R15: 0000000000000001
[ 878.414121] FS: 0000000000000000(0000) GS:ffff9814b7900000(0000) knlGS:0000000000000000
[ 878.414935] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 878.415516] CR2: 00005e106a0554e0 CR3: 0000000112bf0001 CR4: 0000000000772ef0
[ 878.416211] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 878.416907] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 878.417630] PKRU: 55555554

(gdb) l *ceph_msg_data_cursor_init+0x42
0xffffffff823b45a2 is in ceph_msg_data_cursor_init (net/ceph/messenger.c:1070).
1065
1066 void ceph_msg_data_cursor_init(struct ceph_msg_data_cursor *cursor,
1067                                struct ceph_msg *msg, size_t length)
1068 {
1069        BUG_ON(!length);
1070        BUG_ON(length > msg->data_length);
1071        BUG_ON(!msg->num_data_items);
1072
1073        cursor->total_resid = length;
1074        cursor->data = msg->data;

The issue takes place because of this:

[ 202.628853] libceph: net/ceph/messenger_v2.c:2034 prepare_sparse_read_data(): msg->data_length 33792, msg->sparse_read_total 36864

1070        BUG_ON(length > msg->data_length);

The generic/397 test (xfstests) executes such steps:
(1) create encrypted files and directories;
(2) access the created files and folders with encryption key;
(3) access the created files and folders without encryption key.

The issue takes place in this portion of code:

    if (IS_ENCRYPTED(inode)) {
            struct page **pages;
            size_t page_off;

            err = iov_iter_get_pages_alloc2(&subreq->io_iter, &pages, len,
                                            &page_off);
            if (err < 0) {
                    doutc(cl, "%llx.%llx failed to allocate pages, %d\n",
                          ceph_vinop(inode), err);
                    goto out;
            }

            /* should always give us a page-aligned read */
            WARN_ON_ONCE(page_off);
            len = err;
            err = 0;

            osd_req_op_extent_osd_data_pages(req, 0, pages, len, 0, false,
                                             false);

The reason of the issue is that subreq->io_iter.count keeps unaligned
value of length:

[  347.751182] lib/iov_iter.c:1185 __iov_iter_get_pages_alloc(): maxsize 36864, maxpages 4294967295, start 18446659367320516064
[  347.752808] lib/iov_iter.c:1196 __iov_iter_get_pages_alloc(): maxsize 33792, maxpages 4294967295, start 18446659367320516064
[  347.754394] lib/iov_iter.c:1015 iter_folioq_get_pages(): maxsize 33792, maxpages 4294967295, extracted 0, _start_offset 18446659367320516064

This patch simply assigns the aligned value to subreq->io_iter.count
before calling iov_iter_get_pages_alloc2().

[ idryomov: tag the comment with FIXME to make it clear that it's only
            a workaround for netfslib not coexisting with fscrypt nicely
            (this is also noted in another pre-existing comment) ]

Cc: David Howells <dhowells@redhat.com>
Cc: stable@vger.kernel.org
Fixes: ee4cdf7ba857 ("netfs: Speed up buffered reading")
Signed-off-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2025-06-01 17:53:08 +02:00
David Howells
db26d62d79
netfs: Fix undifferentiation of DIO reads from unbuffered reads
On cifs, "DIO reads" (specified by O_DIRECT) need to be differentiated from
"unbuffered reads" (specified by cache=none in the mount parameters).  The
difference is flagged in the protocol and the server may behave
differently: Windows Server will, for example, mandate that DIO reads are
block aligned.

Fix this by adding a NETFS_UNBUFFERED_READ to differentiate this from
NETFS_DIO_READ, parallelling the write differentiation that already exists.
cifs will then do the right thing.

Fixes: 016dc8516aec ("netfs: Implement unbuffered/DIO read support")
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/3444961.1747987072@warthog.procyon.org.uk
Reviewed-by: "Paulo Alcantara (Red Hat)" <pc@manguebit.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
cc: Steve French <sfrench@samba.org>
cc: netfs@lists.linux.dev
cc: v9fs@lists.linux.dev
cc: linux-afs@lists.infradead.org
cc: linux-cifs@vger.kernel.org
cc: ceph-devel@vger.kernel.org
cc: linux-nfs@vger.kernel.org
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-05-23 10:35:03 +02:00
David Howells
20d72b00ca
netfs: Fix the request's work item to not require a ref
When the netfs_io_request struct's work item is queued, it must be supplied
with a ref to the work item struct to prevent it being deallocated whilst
on the queue or whilst it is being processed.  This is tricky to manage as
we have to get a ref before we try and queue it and then we may find it's
already queued and is thus already holding a ref - in which case we have to
try and get rid of the ref again.

The problem comes if we're in BH or IRQ context and need to drop the ref:
if netfs_put_request() reduces the count to 0, we have to do the cleanup -
but the cleanup may need to wait.

Fix this by adding a new work item to the request, ->cleanup_work, and
dispatching that when the refcount hits zero.  That can then synchronously
cancel any outstanding work on the main work item before doing the cleanup.

Adding a new work item also deals with another problem upstream where it's
sometimes changing the work func in the put function and requeuing it -
which has occasionally in the past caused the cleanup to happen
incorrectly.

As a bonus, this allows us to get rid of the 'was_async' parameter from a
bunch of functions.  This indicated whether the put function might not be
permitted to sleep.

Fixes: 3d3c95046742 ("netfs: Provide readahead and readpage netfs helpers")
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/20250519090707.2848510-4-dhowells@redhat.com
cc: Paulo Alcantara <pc@manguebit.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Steve French <stfrench@microsoft.com>
cc: linux-cifs@vger.kernel.org
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-05-21 14:35:20 +02:00
Linus Torvalds
349b7d77f5 A small CephFS encryption-related fix and a dead code cleanup.
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Merge tag 'ceph-for-6.15-rc4' of https://github.com/ceph/ceph-client

Pull ceph fixes from Ilya Dryomov:
 "A small CephFS encryption-related fix and a dead code cleanup"

* tag 'ceph-for-6.15-rc4' of https://github.com/ceph/ceph-client:
  ceph: Fix incorrect flush end position calculation
  ceph: Remove osd_client deadcode
2025-04-25 15:51:28 -07:00
Eric Biggers
b261d22220 lib/crc: remove CONFIG_LIBCRC32C
Now that LIBCRC32C does nothing besides select CRC32, make every option
that selects LIBCRC32C instead select CRC32 directly.  Then remove
LIBCRC32C.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: "Martin K. Petersen" <martin.petersen@oracle.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20250401221600.24878-8-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
2025-04-04 11:31:42 -07:00
David Howells
f452a22046 ceph: Fix incorrect flush end position calculation
In ceph, in fill_fscrypt_truncate(), the end flush position is calculated
by:

                loff_t lend = orig_pos + CEPH_FSCRYPT_BLOCK_SHIFT - 1;

but that's using the block shift not the block size.

Fix this to use the block size instead.

Fixes: 5c64737d2536 ("ceph: add truncate size handling support for fscrypt")
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2025-04-03 21:35:32 +02:00
Linus Torvalds
e63046adef vfs-6.15-rc1.ceph
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Merge tag 'vfs-6.15-rc1.ceph' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull vfs ceph updates from Christian Brauner:
 "This contains the work to remove access to page->index from ceph
  and fixes the test failure observed for ceph with generic/421 by
  refactoring ceph_writepages_start()"

* tag 'vfs-6.15-rc1.ceph' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  fscrypt: Change fscrypt_encrypt_pagecache_blocks() to take a folio
  ceph: Fix error handling in fill_readdir_cache()
  fs: Remove page_mkwrite_check_truncate()
  ceph: Pass a folio to ceph_allocate_page_array()
  ceph: Convert ceph_move_dirty_page_in_page_array() to move_dirty_folio_in_page_array()
  ceph: Remove uses of page from ceph_process_folio_batch()
  ceph: Convert ceph_check_page_before_write() to use a folio
  ceph: Convert writepage_nounlock() to write_folio_nounlock()
  ceph: Convert ceph_readdir_cache_control to store a folio
  ceph: Convert ceph_find_incompatible() to take a folio
  ceph: Use a folio in ceph_page_mkwrite()
  ceph: Remove ceph_writepage()
  ceph: fix generic/421 test failure
  ceph: introduce ceph_submit_write() method
  ceph: introduce ceph_process_folio_batch() method
  ceph: extend ceph_writeback_ctl for ceph_writepages_start() refactoring
2025-03-24 12:17:13 -07:00
Matthew Wilcox (Oracle)
59b59a9431
fscrypt: Change fscrypt_encrypt_pagecache_blocks() to take a folio
ext4 and ceph already have a folio to pass; f2fs needs to be properly
converted but this will do for now.  This removes a reference
to page->index and page->mapping as well as removing a call to
compound_head().

Signed-off-by: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Link: https://lore.kernel.org/r/20250304170224.523141-1-willy@infradead.org
Acked-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-03-05 12:57:15 +01:00
Matthew Wilcox (Oracle)
efbdd92ed9
ceph: Fix error handling in fill_readdir_cache()
__filemap_get_folio() returns an ERR_PTR, not NULL.  There are extensive
assumptions that ctl->folio is NULL, not an error pointer, so it seems
better to fix this one place rather than change all the places which
check ctl->folio.

Fixes: baff9740bc8f ("ceph: Convert ceph_readdir_cache_control to store a folio")
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Link: https://lore.kernel.org/r/20250304154818.250757-1-willy@infradead.org
Cc: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-03-05 11:48:27 +01:00
Matthew Wilcox (Oracle)
d1b452673a
ceph: Pass a folio to ceph_allocate_page_array()
Remove two accesses to page->index.

Signed-off-by: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Link: https://lore.kernel.org/r/20250217185119.430193-10-willy@infradead.org
Tested-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-02-28 11:21:31 +01:00
Matthew Wilcox (Oracle)
ad49fe2b3d
ceph: Convert ceph_move_dirty_page_in_page_array() to move_dirty_folio_in_page_array()
Shorten the name of this internal function by dropping the 'ceph_'
prefix and pass in a folio instead of a page.

Signed-off-by: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Link: https://lore.kernel.org/r/20250217185119.430193-9-willy@infradead.org
Tested-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-02-28 11:21:31 +01:00
Matthew Wilcox (Oracle)
a55cf4fd8f
ceph: Remove uses of page from ceph_process_folio_batch()
Remove uses of page->index and deprecated page APIs.  Saves a lot of
hidden calls to compound_head().

Also convert is_page_index_contiguous() to is_folio_index_contiguous()
and make its arguments const.

Signed-off-by: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Link: https://lore.kernel.org/r/20250217185119.430193-8-willy@infradead.org
Tested-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-02-28 11:21:30 +01:00
Matthew Wilcox (Oracle)
15fdaf2fd6
ceph: Convert ceph_check_page_before_write() to use a folio
Remove the conversion back to a struct page and just use the folio
passed in.

Signed-off-by: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Link: https://lore.kernel.org/r/20250217185119.430193-7-willy@infradead.org
Tested-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-02-28 11:21:30 +01:00
Matthew Wilcox (Oracle)
62171c16da
ceph: Convert writepage_nounlock() to write_folio_nounlock()
Remove references to page->index, page->mapping, thp_size(),
page_offset() and other page APIs in favour of their more efficient
folio replacements.

Signed-off-by: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Link: https://lore.kernel.org/r/20250217185119.430193-6-willy@infradead.org
Tested-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-02-28 11:21:30 +01:00
Matthew Wilcox (Oracle)
baff9740bc
ceph: Convert ceph_readdir_cache_control to store a folio
Pass a folio around instead of a page.  This removes an access to
page->index and a few hidden calls to compound_head().

Signed-off-by: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Link: https://lore.kernel.org/r/20250217185119.430193-5-willy@infradead.org
Tested-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-02-28 11:21:30 +01:00
Matthew Wilcox (Oracle)
f9707a8b5b
ceph: Convert ceph_find_incompatible() to take a folio
Both callers already have the folio.  Pass it in and use it throughout.
Removes some hidden calls to compound_head() and a reference to
page->mapping.

Signed-off-by: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Link: https://lore.kernel.org/r/20250217185119.430193-4-willy@infradead.org
Tested-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-02-28 11:21:30 +01:00
Matthew Wilcox (Oracle)
88a59bda3f
ceph: Use a folio in ceph_page_mkwrite()
Convert the passed page to a folio and use it
throughout ceph_page_mkwrite().  Removes the last call to
page_mkwrite_check_truncate(), the last call to offset_in_thp() and one
of the last calls to thp_size().  Saves a few calls to compound_head().

Signed-off-by: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Link: https://lore.kernel.org/r/20250217185119.430193-3-willy@infradead.org
Tested-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-02-28 11:21:30 +01:00
Matthew Wilcox (Oracle)
19a2881104
ceph: Remove ceph_writepage()
Ceph already has a writepages operation which is preferred over writepage
in all situations except for page migration.  By adding a migrate_folio
operation, there will be no situations in which ->writepage should
be called.  filemap_migrate_folio() is an appropriate operation to use
because the ceph data stored in folio->private does not contain any
reference to the memory address of the folio.

Signed-off-by: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Link: https://lore.kernel.org/r/20250217185119.430193-2-willy@infradead.org
Tested-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-02-28 11:21:30 +01:00
Viacheslav Dubeyko
fd7449d937
ceph: fix generic/421 test failure
The generic/421 fails to finish because of the issue:

Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.894678] INFO: task kworker/u48:0:11 blocked for more than 122 seconds.
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.895403] Not tainted 6.13.0-rc5+ #1
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.895867] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.896633] task:kworker/u48:0 state:D stack:0 pid:11 tgid:11 ppid:2 flags:0x00004000
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.896641] Workqueue: writeback wb_workfn (flush-ceph-24)
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897614] Call Trace:
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897620] <TASK>
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897629] __schedule+0x443/0x16b0
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897637] schedule+0x2b/0x140
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897640] io_schedule+0x4c/0x80
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897643] folio_wait_bit_common+0x11b/0x310
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897646] ? _raw_spin_unlock_irq+0xe/0x50
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897652] ? __pfx_wake_page_function+0x10/0x10
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897655] __folio_lock+0x17/0x30
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897658] ceph_writepages_start+0xca9/0x1fb0
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897663] ? fsnotify_remove_queued_event+0x2f/0x40
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897668] do_writepages+0xd2/0x240
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897672] __writeback_single_inode+0x44/0x350
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897675] writeback_sb_inodes+0x25c/0x550
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897680] wb_writeback+0x89/0x310
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897683] ? finish_task_switch.isra.0+0x97/0x310
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897687] wb_workfn+0xb5/0x410
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897689] process_one_work+0x188/0x3d0
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897692] worker_thread+0x2b5/0x3c0
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897694] ? __pfx_worker_thread+0x10/0x10
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897696] kthread+0xe1/0x120
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897699] ? __pfx_kthread+0x10/0x10
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897701] ret_from_fork+0x43/0x70
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897705] ? __pfx_kthread+0x10/0x10
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897707] ret_from_fork_asm+0x1a/0x30
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897711] </TASK>

There are several issues here:
(1) ceph_kill_sb() doesn't wait ending of flushing
all dirty folios/pages because of racy nature of
mdsc->stopping_blockers. As a result, mdsc->stopping
becomes CEPH_MDSC_STOPPING_FLUSHED too early.
(2) The ceph_inc_osd_stopping_blocker(fsc->mdsc) fails
to increment mdsc->stopping_blockers. Finally,
already locked folios/pages are never been unlocked
and the logic tries to lock the same page second time.
(3) The folio_batch with found dirty pages by
filemap_get_folios_tag() is not processed properly.
And this is why some number of dirty pages simply never
processed and we have dirty folios/pages after unmount
anyway.

This patch fixes the issues by means of:
(1) introducing dirty_folios counter and flush_end_wq
waiting queue in struct ceph_mds_client;
(2) ceph_dirty_folio() increments the dirty_folios
counter;
(3) writepages_finish() decrements the dirty_folios
counter and wake up all waiters on the queue
if dirty_folios counter is equal or lesser than zero;
(4) adding in ceph_kill_sb() method the logic of
checking the value of dirty_folios counter and
waiting if it is bigger than zero;
(5) adding ceph_inc_osd_stopping_blocker() call in the
beginning of the ceph_writepages_start() and
ceph_dec_osd_stopping_blocker() at the end of
the ceph_writepages_start() with the goal to resolve
the racy nature of mdsc->stopping_blockers.

sudo ./check generic/421
FSTYP         -- ceph
PLATFORM      -- Linux/x86_64 ceph-testing-0001 6.13.0+ #137 SMP PREEMPT_DYNAMIC Mon Feb  3 20:30:08 UTC 2025
MKFS_OPTIONS  -- 127.0.0.1:40551:/scratch
MOUNT_OPTIONS -- -o name=fs,secret=<secret>,ms_mode=crc,nowsync,copyfrom 127.0.0.1:40551:/scratch /mnt/scratch

generic/421 7s ...  4s
Ran: generic/421
Passed all 1 tests

Signed-off-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Link: https://lore.kernel.org/r/20250205000249.123054-5-slava@dubeyko.com
Tested-by: David Howells <dhowells@redhat.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-02-28 11:20:16 +01:00
Viacheslav Dubeyko
1551ec61dc
ceph: introduce ceph_submit_write() method
Final responsibility of ceph_writepages_start() is
to submit write requests for processed dirty folios/pages.
The ceph_submit_write() summarize all this logic in
one method.

The generic/421 fails to finish because of the issue:

Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.894678] INFO: task kworker/u48:0:11 blocked for more than 122 seconds.
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.895403] Not tainted 6.13.0-rc5+ #1
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.895867] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.896633] task:kworker/u48:0 state:D stack:0 pid:11 tgid:11 ppid:2 flags:0x00004000
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.896641] Workqueue: writeback wb_workfn (flush-ceph-24)
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897614] Call Trace:
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897620] <TASK>
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897629] __schedule+0x443/0x16b0
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897637] schedule+0x2b/0x140
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897640] io_schedule+0x4c/0x80
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897643] folio_wait_bit_common+0x11b/0x310
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897646] ? _raw_spin_unlock_irq+0xe/0x50
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897652] ? __pfx_wake_page_function+0x10/0x10
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897655] __folio_lock+0x17/0x30
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897658] ceph_writepages_start+0xca9/0x1fb0
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897663] ? fsnotify_remove_queued_event+0x2f/0x40
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897668] do_writepages+0xd2/0x240
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897672] __writeback_single_inode+0x44/0x350
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897675] writeback_sb_inodes+0x25c/0x550
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897680] wb_writeback+0x89/0x310
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897683] ? finish_task_switch.isra.0+0x97/0x310
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897687] wb_workfn+0xb5/0x410
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897689] process_one_work+0x188/0x3d0
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897692] worker_thread+0x2b5/0x3c0
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897694] ? __pfx_worker_thread+0x10/0x10
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897696] kthread+0xe1/0x120
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897699] ? __pfx_kthread+0x10/0x10
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897701] ret_from_fork+0x43/0x70
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897705] ? __pfx_kthread+0x10/0x10
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897707] ret_from_fork_asm+0x1a/0x30
Jan 3 14:25:27 ceph-testing-0001 kernel: [ 369.897711] </TASK>

There are two problems here:

if (!ceph_inc_osd_stopping_blocker(fsc->mdsc)) {
     rc = -EIO;
     goto release_folios;
}

(1) ceph_kill_sb() doesn't wait ending of flushing
all dirty folios/pages because of racy nature of
mdsc->stopping_blockers. As a result, mdsc->stopping
becomes CEPH_MDSC_STOPPING_FLUSHED too early.
(2) The ceph_inc_osd_stopping_blocker(fsc->mdsc) fails
to increment mdsc->stopping_blockers. Finally,
already locked folios/pages are never been unlocked
and the logic tries to lock the same page second time.

This patch implements refactoring of ceph_submit_write()
and also it solves the second issue.

Signed-off-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Link: https://lore.kernel.org/r/20250205000249.123054-4-slava@dubeyko.com
Tested-by: David Howells <dhowells@redhat.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-02-28 11:20:16 +01:00
Viacheslav Dubeyko
ce80b76dd3
ceph: introduce ceph_process_folio_batch() method
First step of ceph_writepages_start() logic is
of finding the dirty memory folios and processing it.
This patch introduces ceph_process_folio_batch()
method that moves this logic into dedicated method.

The ceph_writepages_start() has this logic:

if (ceph_wbc.locked_pages == 0)
    lock_page(page);  /* first page */
else if (!trylock_page(page))
    break;

<skipped>

if (folio_test_writeback(folio) ||
    folio_test_private_2(folio) /* [DEPRECATED] */) {
      if (wbc->sync_mode == WB_SYNC_NONE) {
          doutc(cl, "%p under writeback\n", folio);
          folio_unlock(folio);
          continue;
      }
      doutc(cl, "waiting on writeback %p\n", folio);
      folio_wait_writeback(folio);
      folio_wait_private_2(folio); /* [DEPRECATED] */
}

The problem here that folio/page is locked here at first
and it is by set_page_writeback(page) later before
submitting the write request. The folio/page is unlocked
by writepages_finish() after finishing the write
request. It means that logic of checking folio_test_writeback()
and folio_wait_writeback() never works because page is locked
and it cannot be locked again until write request completion.
However, for majority of folios/pages the trylock_page()
is used. As a result, multiple threads can try to lock the same
folios/pages multiple times even if they are under writeback
already. It makes this logic more compute intensive than
it is necessary.

This patch changes this logic:

if (folio_test_writeback(folio) ||
    folio_test_private_2(folio) /* [DEPRECATED] */) {
      if (wbc->sync_mode == WB_SYNC_NONE) {
          doutc(cl, "%p under writeback\n", folio);
          folio_unlock(folio);
          continue;
      }
      doutc(cl, "waiting on writeback %p\n", folio);
      folio_wait_writeback(folio);
      folio_wait_private_2(folio); /* [DEPRECATED] */
}

if (ceph_wbc.locked_pages == 0)
    lock_page(page);  /* first page */
else if (!trylock_page(page))
    break;

This logic should exclude the ignoring of writeback
state of folios/pages.

Signed-off-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Link: https://lore.kernel.org/r/20250205000249.123054-3-slava@dubeyko.com
Tested-by: David Howells <dhowells@redhat.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-02-28 11:20:15 +01:00
Viacheslav Dubeyko
f08068df4a
ceph: extend ceph_writeback_ctl for ceph_writepages_start() refactoring
The ceph_writepages_start() has unreasonably huge size and
complex logic that makes this method hard to understand.
Current state of the method's logic makes bug fix really
hard task. This patch extends the struct ceph_writeback_ctl
with the goal to make ceph_writepages_start() method
more compact and easy to understand by means of deep refactoring.

Signed-off-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Link: https://lore.kernel.org/r/20250205000249.123054-2-slava@dubeyko.com
Tested-by: David Howells <dhowells@redhat.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-02-28 11:20:15 +01:00
NeilBrown
3f92c7b576
ceph: return the correct dentry on mkdir
ceph already splices the correct dentry (in splice_dentry()) from the
result of mkdir but does nothing more with it.

Now that ->mkdir can return a dentry, return the correct dentry.

Note that previously ceph_mkdir() could call
   ceph_init_inode_acls()
on the inode from the wrong dentry, which would be NULL.  This
is safe as ceph_init_inode_acls() checks for NULL, but is not
strictly correct.  With this patch, the inode for the returned dentry
is passed to ceph_init_inode_acls().

Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Link: https://lore.kernel.org/r/20250227013949.536172-4-neilb@suse.de
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-02-27 20:00:17 +01:00
NeilBrown
88d5baf690
Change inode_operations.mkdir to return struct dentry *
Some filesystems, such as NFS, cifs, ceph, and fuse, do not have
complete control of sequencing on the actual filesystem (e.g.  on a
different server) and may find that the inode created for a mkdir
request already exists in the icache and dcache by the time the mkdir
request returns.  For example, if the filesystem is mounted twice the
directory could be visible on the other mount before it is on the
original mount, and a pair of name_to_handle_at(), open_by_handle_at()
calls could instantiate the directory inode with an IS_ROOT() dentry
before the first mkdir returns.

This means that the dentry passed to ->mkdir() may not be the one that
is associated with the inode after the ->mkdir() completes.  Some
callers need to interact with the inode after the ->mkdir completes and
they currently need to perform a lookup in the (rare) case that the
dentry is no longer hashed.

This lookup-after-mkdir requires that the directory remains locked to
avoid races.  Planned future patches to lock the dentry rather than the
directory will mean that this lookup cannot be performed atomically with
the mkdir.

To remove this barrier, this patch changes ->mkdir to return the
resulting dentry if it is different from the one passed in.
Possible returns are:
  NULL - the directory was created and no other dentry was used
  ERR_PTR() - an error occurred
  non-NULL - this other dentry was spliced in

This patch only changes file-systems to return "ERR_PTR(err)" instead of
"err" or equivalent transformations.  Subsequent patches will make
further changes to some file-systems to return a correct dentry.

Not all filesystems reliably result in a positive hashed dentry:

- NFS, cifs, hostfs will sometimes need to perform a lookup of
  the name to get inode information.  Races could result in this
  returning something different. Note that this lookup is
  non-atomic which is what we are trying to avoid.  Placing the
  lookup in filesystem code means it only happens when the filesystem
  has no other option.
- kernfs and tracefs leave the dentry negative and the ->revalidate
  operation ensures that lookup will be called to correctly populate
  the dentry.  This could be fixed but I don't think it is important
  to any of the users of vfs_mkdir() which look at the dentry.

The recommendation to use
    d_drop();d_splice_alias()
is ugly but fits with current practice.  A planned future patch will
change this.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: NeilBrown <neilb@suse.de>
Link: https://lore.kernel.org/r/20250227013949.536172-2-neilb@suse.de
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-02-27 20:00:17 +01:00
Linus Torvalds
626d1a1e99 A fix for a memory leak from Antoine (marked for stable) and two
cleanups from Liang and Slava, all in CephFS.
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Merge tag 'ceph-for-6.14-rc1' of https://github.com/ceph/ceph-client

Pull ceph updates from Ilya Dryomov:
 "A fix for a memory leak from Antoine (marked for stable) and two
  cleanups from Liang and Slava"

* tag 'ceph-for-6.14-rc1' of https://github.com/ceph/ceph-client:
  ceph: exchange hardcoded value on NAME_MAX
  ceph: streamline request head structures in MDS client
  ceph: fix memory leak in ceph_mds_auth_match()
2025-01-31 10:30:34 -08:00
Linus Torvalds
d3d90cc289 Provide stable parent and name to ->d_revalidate() instances
Most of the filesystem methods where we care about dentry name
 and parent have their stability guaranteed by the callers;
 ->d_revalidate() is the major exception.
 
 It's easy enough for callers to supply stable values for
 expected name and expected parent of the dentry being
 validated.  That kills quite a bit of boilerplate in
 ->d_revalidate() instances, along with a bunch of races
 where they used to access ->d_name without sufficient
 precautions.
 
 Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Merge tag 'pull-revalidate' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull vfs d_revalidate updates from Al Viro:
 "Provide stable parent and name to ->d_revalidate() instances

  Most of the filesystem methods where we care about dentry name and
  parent have their stability guaranteed by the callers;
  ->d_revalidate() is the major exception.

  It's easy enough for callers to supply stable values for expected name
  and expected parent of the dentry being validated. That kills quite a
  bit of boilerplate in ->d_revalidate() instances, along with a bunch
  of races where they used to access ->d_name without sufficient
  precautions"

* tag 'pull-revalidate' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  9p: fix ->rename_sem exclusion
  orangefs_d_revalidate(): use stable parent inode and name passed by caller
  ocfs2_dentry_revalidate(): use stable parent inode and name passed by caller
  nfs: fix ->d_revalidate() UAF on ->d_name accesses
  nfs{,4}_lookup_validate(): use stable parent inode passed by caller
  gfs2_drevalidate(): use stable parent inode and name passed by caller
  fuse_dentry_revalidate(): use stable parent inode and name passed by caller
  vfat_revalidate{,_ci}(): use stable parent inode passed by caller
  exfat_d_revalidate(): use stable parent inode passed by caller
  fscrypt_d_revalidate(): use stable parent inode passed by caller
  ceph_d_revalidate(): propagate stable name down into request encoding
  ceph_d_revalidate(): use stable parent inode passed by caller
  afs_d_revalidate(): use stable name and parent inode passed by caller
  Pass parent directory inode and expected name to ->d_revalidate()
  generic_ci_d_compare(): use shortname_storage
  ext4 fast_commit: make use of name_snapshot primitives
  dissolve external_name.u into separate members
  make take_dentry_name_snapshot() lockless
  dcache: back inline names with a struct-wrapped array of unsigned long
  make sure that DNAME_INLINE_LEN is a multiple of word size
2025-01-30 09:13:35 -08:00
Al Viro
541795cb0b ceph_d_revalidate(): propagate stable name down into request encoding
Currently get_fscrypt_altname() requires ->r_dentry->d_name to be stable
and it gets that in almost all cases.  The only exception is ->d_revalidate(),
where we have a stable name, but it's passed separately - dentry->d_name
is not stable there.

Propagate it down to get_fscrypt_altname() as a new field of struct
ceph_mds_request - ->r_dname, to be used instead ->r_dentry->d_name
when non-NULL.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2025-01-27 19:25:23 -05:00
Al Viro
bf636ed4a9 ceph_d_revalidate(): use stable parent inode passed by caller
No need to mess with the boilerplate for obtaining what we already
have.  Note that ceph is one of the "will want a path from filesystem
root if we want to talk to server" cases, so the name of the last
component is of little use - it is passed to fscrypt_d_revalidate()
and it's used to deal with (also crypt-related) case in request
marshalling, when encrypted name turns out to be too long.  The former
is not a problem, but the latter is racy; that part will be handled
in the next commit.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2025-01-27 19:25:23 -05:00
Al Viro
5be1fa8abd Pass parent directory inode and expected name to ->d_revalidate()
->d_revalidate() often needs to access dentry parent and name; that has
to be done carefully, since the locking environment varies from caller
to caller.  We are not guaranteed that dentry in question will not be
moved right under us - not unless the filesystem is such that nothing
on it ever gets renamed.

It can be dealt with, but that results in boilerplate code that isn't
even needed - the callers normally have just found the dentry via dcache
lookup and want to verify that it's in the right place; they already
have the values of ->d_parent and ->d_name stable.  There is a couple
of exceptions (overlayfs and, to less extent, ecryptfs), but for the
majority of calls that song and dance is not needed at all.

It's easier to make ecryptfs and overlayfs find and pass those values if
there's a ->d_revalidate() instance to be called, rather than doing that
in the instances.

This commit only changes the calling conventions; making use of supplied
values is left to followups.

NOTE: some instances need more than just the parent - things like CIFS
may need to build an entire path from filesystem root, so they need
more precautions than the usual boilerplate.  This series doesn't
do anything to that need - these filesystems have to keep their locking
mechanisms (rename_lock loops, use of dentry_path_raw(), private rwsem
a-la v9fs).

One thing to keep in mind when using name is that name->name will normally
point into the pathname being resolved; the filename in question occupies
name->len bytes starting at name->name, and there is NUL somewhere after it,
but it the next byte might very well be '/' rather than '\0'.  Do not
ignore name->len.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Gabriel Krisman Bertazi <gabriel@krisman.be>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2025-01-27 19:25:23 -05:00
Viacheslav Dubeyko
3981be13ec ceph: exchange hardcoded value on NAME_MAX
Initially, ceph_fs_debugfs_init() had temporary
name buffer with hardcoded length of 80 symbols.
Then, it was hardcoded again for 100 symbols.
Finally, it makes sense to exchange hardcoded
value on properly defined constant and 255 symbols
should be enough for any name case.

Signed-off-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Reviewed-by: Patrick Donnelly <pdonnell@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2025-01-27 16:07:42 +01:00
Liang Jie
2f0805d7c0 ceph: streamline request head structures in MDS client
The existence of the ceph_mds_request_head_old structure in the MDS
client code is no longer required due to improvements in handling
different MDS request header versions. This patch removes the now
redundant ceph_mds_request_head_old structure and replaces its usage
with the flexible and extensible ceph_mds_request_head structure.

Changes include:
- Modification of find_legacy_request_head to directly cast the
  pointer to ceph_mds_request_head_legacy without going through the
  old structure.
- Update sizeof calculations in create_request_message to use
  offsetofend for consistency and future-proofing, rather than
  referencing the old structure.
- Use of the structured ceph_mds_request_head directly instead of the
  old one.

Additionally, this consolidation normalizes the handling of
request_head_version v1 to align with versions v2 and v3, leading to
a more consistent and maintainable codebase.

These changes simplify the codebase and reduce potential confusion
stemming from the existence of an obsolete structure.

Signed-off-by: Liang Jie <liangjie@lixiang.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2025-01-27 16:07:42 +01:00
Linus Torvalds
c159dfbdd4 Mainly individually changelogged singleton patches. The patch series in
this pull are:
 
 - "lib min_heap: Improve min_heap safety, testing, and documentation"
   from Kuan-Wei Chiu provides various tightenings to the min_heap library
   code.
 
 - "xarray: extract __xa_cmpxchg_raw" from Tamir Duberstein preforms some
   cleanup and Rust preparation in the xarray library code.
 
 - "Update reference to include/asm-<arch>" from Geert Uytterhoeven fixes
   pathnames in some code comments.
 
 - "Converge on using secs_to_jiffies()" from Easwar Hariharan uses the
   new secs_to_jiffies() in various places where that is appropriate.
 
 - "ocfs2, dlmfs: convert to the new mount API" from Eric Sandeen
   switches two filesystems to the new mount API.
 
 - "Convert ocfs2 to use folios" from Matthew Wilcox does that.
 
 - "Remove get_task_comm() and print task comm directly" from Yafang Shao
   removes now-unneeded calls to get_task_comm() in various places.
 
 - "squashfs: reduce memory usage and update docs" from Phillip Lougher
   implements some memory savings in squashfs and performs some
   maintainability work.
 
 - "lib: clarify comparison function requirements" from Kuan-Wei Chiu
   tightens the sort code's behaviour and adds some maintenance work.
 
 - "nilfs2: protect busy buffer heads from being force-cleared" from
   Ryusuke Konishi fixes an issues in nlifs when the fs is presented with a
   corrupted image.
 
 - "nilfs2: fix kernel-doc comments for function return values" from
   Ryusuke Konishi fixes some nilfs kerneldoc.
 
 - "nilfs2: fix issues with rename operations" from Ryusuke Konishi
   addresses some nilfs BUG_ONs which syzbot was able to trigger.
 
 - "minmax.h: Cleanups and minor optimisations" from David Laight
   does some maintenance work on the min/max library code.
 
 - "Fixes and cleanups to xarray" from Kemeng Shi does maintenance work
   on the xarray library code.
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Merge tag 'mm-nonmm-stable-2025-01-24-23-16' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull non-MM updates from Andrew Morton:
 "Mainly individually changelogged singleton patches. The patch series
  in this pull are:

   - "lib min_heap: Improve min_heap safety, testing, and documentation"
     from Kuan-Wei Chiu provides various tightenings to the min_heap
     library code

   - "xarray: extract __xa_cmpxchg_raw" from Tamir Duberstein preforms
     some cleanup and Rust preparation in the xarray library code

   - "Update reference to include/asm-<arch>" from Geert Uytterhoeven
     fixes pathnames in some code comments

   - "Converge on using secs_to_jiffies()" from Easwar Hariharan uses
     the new secs_to_jiffies() in various places where that is
     appropriate

   - "ocfs2, dlmfs: convert to the new mount API" from Eric Sandeen
     switches two filesystems to the new mount API

   - "Convert ocfs2 to use folios" from Matthew Wilcox does that

   - "Remove get_task_comm() and print task comm directly" from Yafang
     Shao removes now-unneeded calls to get_task_comm() in various
     places

   - "squashfs: reduce memory usage and update docs" from Phillip
     Lougher implements some memory savings in squashfs and performs
     some maintainability work

   - "lib: clarify comparison function requirements" from Kuan-Wei Chiu
     tightens the sort code's behaviour and adds some maintenance work

   - "nilfs2: protect busy buffer heads from being force-cleared" from
     Ryusuke Konishi fixes an issues in nlifs when the fs is presented
     with a corrupted image

   - "nilfs2: fix kernel-doc comments for function return values" from
     Ryusuke Konishi fixes some nilfs kerneldoc

   - "nilfs2: fix issues with rename operations" from Ryusuke Konishi
     addresses some nilfs BUG_ONs which syzbot was able to trigger

   - "minmax.h: Cleanups and minor optimisations" from David Laight does
     some maintenance work on the min/max library code

   - "Fixes and cleanups to xarray" from Kemeng Shi does maintenance
     work on the xarray library code"

* tag 'mm-nonmm-stable-2025-01-24-23-16' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (131 commits)
  ocfs2: use str_yes_no() and str_no_yes() helper functions
  include/linux/lz4.h: add some missing macros
  Xarray: use xa_mark_t in xas_squash_marks() to keep code consistent
  Xarray: remove repeat check in xas_squash_marks()
  Xarray: distinguish large entries correctly in xas_split_alloc()
  Xarray: move forward index correctly in xas_pause()
  Xarray: do not return sibling entries from xas_find_marked()
  ipc/util.c: complete the kernel-doc function descriptions
  gcov: clang: use correct function param names
  latencytop: use correct kernel-doc format for func params
  minmax.h: remove some #defines that are only expanded once
  minmax.h: simplify the variants of clamp()
  minmax.h: move all the clamp() definitions after the min/max() ones
  minmax.h: use BUILD_BUG_ON_MSG() for the lo < hi test in clamp()
  minmax.h: reduce the #define expansion of min(), max() and clamp()
  minmax.h: update some comments
  minmax.h: add whitespace around operators and after commas
  nilfs2: do not update mtime of renamed directory that is not moved
  nilfs2: handle errors that nilfs_prepare_chunk() may return
  CREDITS: fix spelling mistake
  ...
2025-01-26 17:50:53 -08:00
Linus Torvalds
f96a974170 lsm/stable-6.14 PR 20250121
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Merge tag 'lsm-pr-20250121' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm

Pull lsm updates from Paul Moore:

 - Improved handling of LSM "secctx" strings through lsm_context struct

   The LSM secctx string interface is from an older time when only one
   LSM was supported, migrate over to the lsm_context struct to better
   support the different LSMs we now have and make it easier to support
   new LSMs in the future.

   These changes explain the Rust, VFS, and networking changes in the
   diffstat.

 - Only build lsm_audit.c if CONFIG_SECURITY and CONFIG_AUDIT are
   enabled

   Small tweak to be a bit smarter about when we build the LSM's common
   audit helpers.

 - Check for absurdly large policies from userspace in SafeSetID

   SafeSetID policies rules are fairly small, basically just "UID:UID",
   it easy to impose a limit of KMALLOC_MAX_SIZE on policy writes which
   helps quiet a number of syzbot related issues. While work is being
   done to address the syzbot issues through other mechanisms, this is a
   trivial and relatively safe fix that we can do now.

 - Various minor improvements and cleanups

   A collection of improvements to the kernel selftests, constification
   of some function parameters, removing redundant assignments, and
   local variable renames to improve readability.

* tag 'lsm-pr-20250121' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm:
  lockdown: initialize local array before use to quiet static analysis
  safesetid: check size of policy writes
  net: corrections for security_secid_to_secctx returns
  lsm: rename variable to avoid shadowing
  lsm: constify function parameters
  security: remove redundant assignment to return variable
  lsm: Only build lsm_audit.c if CONFIG_SECURITY and CONFIG_AUDIT are set
  selftests: refactor the lsm `flags_overset_lsm_set_self_attr` test
  binder: initialize lsm_context structure
  rust: replace lsm context+len with lsm_context
  lsm: secctx provider check on release
  lsm: lsm_context in security_dentry_init_security
  lsm: use lsm_context in security_inode_getsecctx
  lsm: replace context+len with lsm_context
  lsm: ensure the correct LSM context releaser
2025-01-21 20:03:04 -08:00
Linus Torvalds
ca56a74a31 vfs-6.14-rc1.netfs
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Merge tag 'vfs-6.14-rc1.netfs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull vfs netfs updates from Christian Brauner:
 "This contains read performance improvements and support for monolithic
  single-blob objects that have to be read/written as such (e.g. AFS
  directory contents). The implementation of the two parts is interwoven
  as each makes the other possible.

   - Read performance improvements

     The read performance improvements are intended to speed up some
     loss of performance detected in cifs and to a lesser extend in afs.

     The problem is that we queue too many work items during the
     collection of read results: each individual subrequest is collected
     by its own work item, and then they have to interact with each
     other when a series of subrequests don't exactly align with the
     pattern of folios that are being read by the overall request.

     Whilst the processing of the pages covered by individual
     subrequests as they complete potentially allows folios to be woken
     in parallel and with minimum delay, it can shuffle wakeups for
     sequential reads out of order - and that is the most common I/O
     pattern.

     The final assessment and cleanup of an operation is then held up
     until the last I/O completes - and for a synchronous sequential
     operation, this means the bouncing around of work items just adds
     latency.

     Two changes have been made to make this work:

     (1) All collection is now done in a single "work item" that works
         progressively through the subrequests as they complete (and
         also dispatches retries as necessary).

     (2) For readahead and AIO, this work item be done on a workqueue
         and can run in parallel with the ultimate consumer of the data;
         for synchronous direct or unbuffered reads, the collection is
         run in the application thread and not offloaded.

     Functions such as smb2_readv_callback() then just tell netfslib
     that the subrequest has terminated; netfslib does a minimal bit of
     processing on the spot - stat counting and tracing mostly - and
     then queues/wakes up the worker. This simplifies the logic as the
     collector just walks sequentially through the subrequests as they
     complete and walks through the folios, if buffered, unlocking them
     as it goes. It also keeps to a minimum the amount of latency
     injected into the filesystem's low-level I/O handling

     The way netfs supports filesystems using the deprecated
     PG_private_2 flag is changed: folios are flagged and added to a
     write request as they complete and that takes care of scheduling
     the writes to the cache. The originating read request can then just
     unlock the pages whatever happens.

   - Single-blob object support

     Single-blob objects are files for which the content of the file
     must be read from or written to the server in a single operation
     because reading them in parts may yield inconsistent results. AFS
     directories are an example of this as there exists the possibility
     that the contents are generated on the fly and would differ between
     reads or might change due to third party interference.

     Such objects will be written to and retrieved from the cache if one
     is present, though we allow/may need to propose multiple
     subrequests to do so. The important part is that read from/write to
     the *server* is monolithic.

     Single blob reading is, for the moment, fully synchronous and does
     result collection in the application thread and, also for the
     moment, the API is supplied the buffer in the form of a folio_queue
     chain rather than using the pagecache.

   - Related afs changes

     This series makes a number of changes to the kafs filesystem,
     primarily in the area of directory handling:

      - AFS's FetchData RPC reply processing is made partially
        asynchronous which allows the netfs_io_request's outstanding
        operation counter to be removed as part of reducing the
        collection to a single work item.

      - Directory and symlink reading are plumbed through netfslib using
        the single-blob object API and are now cacheable with fscache.
        This also allows the afs_read struct to be eliminated and
        netfs_io_subrequest to be used directly instead.

      - Directory and symlink content are now stored in a folio_queue
        buffer rather than in the pagecache. This means we don't require
        the RCU read lock and xarray iteration to access it, and folios
        won't randomly disappear under us because the VM wants them
        back.

      - The vnode operation lock is changed from a mutex struct to a
        private lock implementation. The problem is that the lock now
        needs to be dropped in a separate thread and mutexes don't
        permit that.

      - When a new directory or symlink is created, we now initialise it
        locally and mark it valid rather than downloading it (we know
        what it's likely to look like).

      - We now use the in-directory hashtable to reduce the number of
        entries we need to scan when doing a lookup. The edit routines
        have to maintain the hash chains.

      - Cancellation (e.g. by signal) of an async call after the
        rxrpc_call has been set up is now offloaded to the worker thread
        as there will be a notification from rxrpc upon completion. This
        avoids a double cleanup.

   - A "rolling buffer" implementation is created to abstract out the
     two separate folio_queue chaining implementations I had (one for
     read and one for write).

   - Functions are provided to create/extend a buffer in a folio_queue
     chain and tear it down again.

     This is used to handle AFS directories, but could also be used to
     create bounce buffers for content crypto and transport crypto.

   - The was_async argument is dropped from netfs_read_subreq_terminated()

     Instead we wake the read collection work item by either queuing it
     or waking up the app thread.

   - We don't need to use BH-excluding locks when communicating between
     the issuing thread and the collection thread as neither of them now
     run in BH context.

   - Also included are a number of new tracepoints; a split of the
     netfslib write collection code to put retrying into its own file
     (it gets more complicated with content encryption).

   - There are also some minor fixes AFS included, including fixing the
     AFS directory format struct layout, reducing some directory
     over-invalidation and making afs_mkdir() translate EEXIST to
     ENOTEMPY (which is not available on all systems the servers
     support).

   - Finally, there's a patch to try and detect entry into the folio
     unlock function with no folio_queue structs in the buffer (which
     isn't allowed in the cases that can get there).

     This is a debugging patch, but should be minimal overhead"

* tag 'vfs-6.14-rc1.netfs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (31 commits)
  netfs: Report on NULL folioq in netfs_writeback_unlock_folios()
  afs: Add a tracepoint for afs_read_receive()
  afs: Locally initialise the contents of a new symlink on creation
  afs: Use the contained hashtable to search a directory
  afs: Make afs_mkdir() locally initialise a new directory's content
  netfs: Change the read result collector to only use one work item
  afs: Make {Y,}FS.FetchData an asynchronous operation
  afs: Fix cleanup of immediately failed async calls
  afs: Eliminate afs_read
  afs: Use netfslib for symlinks, allowing them to be cached
  afs: Use netfslib for directories
  afs: Make afs_init_request() get a key if not given a file
  netfs: Add support for caching single monolithic objects such as AFS dirs
  netfs: Add functions to build/clean a buffer in a folio_queue
  afs: Add more tracepoints to do with tracking validity
  cachefiles: Add auxiliary data trace
  cachefiles: Add some subrequest tracepoints
  netfs: Remove some extraneous directory invalidations
  afs: Fix directory format encoding struct
  afs: Fix EEXIST error returned from afs_rmdir() to be ENOTEMPTY
  ...
2025-01-20 09:29:11 -08:00
Antoine Viallon
3b7d93db45 ceph: fix memory leak in ceph_mds_auth_match()
We now free the temporary target path substring allocation on every
possible branch, instead of omitting the default branch.  In some
cases, a memory leak occured, which could rapidly crash the system
(depending on how many file accesses were attempted).

This was detected in production because it caused a continuous memory
growth, eventually triggering kernel OOM and completely hard-locking
the kernel.

Relevant kmemleak stacktrace:

    unreferenced object 0xffff888131e69900 (size 128):
      comm "git", pid 66104, jiffies 4295435999
      hex dump (first 32 bytes):
        76 6f 6c 75 6d 65 73 2f 63 6f 6e 74 61 69 6e 65  volumes/containe
        72 73 2f 67 69 74 65 61 2f 67 69 74 65 61 2f 67  rs/gitea/gitea/g
      backtrace (crc 2f3bb450):
        [<ffffffffaa68fb49>] __kmalloc_noprof+0x359/0x510
        [<ffffffffc32bf1df>] ceph_mds_check_access+0x5bf/0x14e0 [ceph]
        [<ffffffffc3235722>] ceph_open+0x312/0xd80 [ceph]
        [<ffffffffaa7dd786>] do_dentry_open+0x456/0x1120
        [<ffffffffaa7e3729>] vfs_open+0x79/0x360
        [<ffffffffaa832875>] path_openat+0x1de5/0x4390
        [<ffffffffaa834fcc>] do_filp_open+0x19c/0x3c0
        [<ffffffffaa7e44a1>] do_sys_openat2+0x141/0x180
        [<ffffffffaa7e4945>] __x64_sys_open+0xe5/0x1a0
        [<ffffffffac2cc2f7>] do_syscall_64+0xb7/0x210
        [<ffffffffac400130>] entry_SYSCALL_64_after_hwframe+0x77/0x7f

It can be triggered by mouting a subdirectory of a CephFS filesystem,
and then trying to access files on this subdirectory with an auth token
using a path-scoped capability:

    $ ceph auth get client.services
    [client.services]
            key = REDACTED
            caps mds = "allow rw fsname=cephfs path=/volumes/"
            caps mon = "allow r fsname=cephfs"
            caps osd = "allow rw tag cephfs data=cephfs"

    $ cat /proc/self/mounts
    services@[REDACTED].cephfs=/volumes/containers /ceph/containers ceph rw,noatime,name=services,secret=<hidden>,ms_mode=prefer-crc,mount_timeout=300,acl,mon_addr=[REDACTED]:3300,recover_session=clean 0 0

    $ seq 1 1000000 | xargs -P32 --replace={} touch /ceph/containers/file-{} && \
    seq 1 1000000 | xargs -P32 --replace={} cat /ceph/containers/file-{}

[ idryomov: combine if statements, rename rc to path_matched and make
            it a bool, formatting ]

Cc: stable@vger.kernel.org
Fixes: 596afb0b8933 ("ceph: add ceph_mds_check_access() helper")
Signed-off-by: Antoine Viallon <antoine@lesviallon.fr>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2025-01-15 20:35:06 +01:00
Easwar Hariharan
f5ea0319ef ceph: convert timeouts to secs_to_jiffies()
Commit b35108a51cf7 ("jiffies: Define secs_to_jiffies()") introduced
secs_to_jiffies().  As the value here is a multiple of 1000, use
secs_to_jiffies() instead of msecs_to_jiffies to avoid the multiplication.

This is converted using scripts/coccinelle/misc/secs_to_jiffies.cocci with
the following Coccinelle rules:

@@ constant C; @@

- msecs_to_jiffies(C * 1000)
+ secs_to_jiffies(C)

@@ constant C; @@

- msecs_to_jiffies(C * MSEC_PER_SEC)
+ secs_to_jiffies(C)

Link: https://lkml.kernel.org/r/20241210-converge-secs-to-jiffies-v3-17-ddfefd7e9f2a@linux.microsoft.com
Signed-off-by: Easwar Hariharan <eahariha@linux.microsoft.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Andrew Lunn <andrew+netdev@lunn.ch>
Cc: Anna-Maria Behnsen <anna-maria@linutronix.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Daniel Mack <daniel@zonque.org>
Cc: David Airlie <airlied@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Dick Kennedy <dick.kennedy@broadcom.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Florian Fainelli <florian.fainelli@broadcom.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Haojian Zhuang <haojian.zhuang@gmail.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Ilya Dryomov <idryomov@gmail.com>
Cc: Jack Wang <jinpu.wang@cloud.ionos.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: James Smart <james.smart@broadcom.com>
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Jeff Johnson <jjohnson@kernel.org>
Cc: Jeff Johnson <quic_jjohnson@quicinc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jeroen de Borst <jeroendb@google.com>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Joe Lawrence <joe.lawrence@redhat.com>
Cc: Johan Hedberg <johan.hedberg@gmail.com>
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Jozsef Kadlecsik <kadlec@netfilter.org>
Cc: Julia Lawall <julia.lawall@inria.fr>
Cc: Kalle Valo <kvalo@kernel.org>
Cc: Louis Peens <louis.peens@corigine.com>
Cc: Lucas De Marchi <lucas.demarchi@intel.com>
Cc: Luiz Augusto von Dentz <luiz.dentz@gmail.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Marcel Holtmann <marcel@holtmann.org>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Miroslav Benes <mbenes@suse.cz>
Cc: Naveen N Rao <naveen@kernel.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Nicolas Palix <nicolas.palix@imag.fr>
Cc: Oded Gabbay <ogabbay@kernel.org>
Cc: Ofir Bitton <obitton@habana.ai>
Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Praveen Kaligineedi <pkaligineedi@google.com>
Cc: Ray Jui <rjui@broadcom.com>
Cc: Robert Jarzmik <robert.jarzmik@free.fr>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Roger Pau Monné <roger.pau@citrix.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Scott Branden <sbranden@broadcom.com>
Cc: Shailend Chand <shailend@google.com>
Cc: Simona Vetter <simona@ffwll.ch>
Cc: Simon Horman <horms@kernel.org>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Takashi Iwai <tiwai@suse.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-01-12 20:21:04 -08:00
David Howells
e2d46f2ec3
netfs: Change the read result collector to only use one work item
Change the way netfslib collects read results to do all the collection for
a particular read request using a single work item that walks along the
subrequest queue as subrequests make progress or complete, unlocking folios
progressively rather than doing the unlock in parallel as parallel requests
come in.

The code is remodelled to be more like the write-side code, though only
using a single stream.  This makes it more directly comparable and thus
easier to duplicate fixes between the two sides.

This has a number of advantages:

 (1) It's simpler.  There doesn't need to be a complex donation mechanism
     to handle mismatches between the size and alignment of subrequests and
     folios.  The collector unlocks folios as the subrequests covering each
     complete.

 (2) It should cause less scheduler overhead as there's a single work item
     in play unlocking pages in parallel when a read gets split up into a
     lot of subrequests instead of one per subrequest.

     Whilst the parallellism is nice in theory, in practice, the vast
     majority of loads are sequential reads of the whole file, so
     committing a bunch of threads to unlocking folios out of order doesn't
     help in those cases.

 (3) It should make it easier to implement content decryption.  A folio
     cannot be decrypted until all the requests that contribute to it have
     completed - and, again, most loads are sequential and so, most of the
     time, we want to begin decryption sequentially (though it's great if
     the decryption can happen in parallel).

There is a disadvantage in that we're losing the ability to decrypt and
unlock things on an as-things-arrive basis which may affect some
applications.

Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/20241216204124.3752367-28-dhowells@redhat.com
cc: Jeff Layton <jlayton@kernel.org>
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-12-20 22:34:08 +01:00
David Howells
31fc366aa7
netfs: Drop the was_async arg from netfs_read_subreq_terminated()
Drop the was_async argument from netfs_read_subreq_terminated().  Almost
every caller is either in process context and passes false.  Some
filesystems delegate the call to a workqueue to avoid doing the work in
their network message queue parsing thread.

The only exception is netfs_cache_read_terminated() which handles
completion in the cache - which is usually a callback from the backing
filesystem in softirq context, though it can be from process context if an
error occurred.  In this case, delegate to a workqueue.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/r/CAHk-=wiVC5Cgyz6QKXFu6fTaA6h4CjexDR-OV9kL6Vo5x9v8=A@mail.gmail.com/
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/20241216204124.3752367-10-dhowells@redhat.com
cc: Jeff Layton <jlayton@kernel.org>
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-12-20 22:34:03 +01:00
David Howells
360157829e
netfs: Drop the error arg from netfs_read_subreq_terminated()
Drop the error argument from netfs_read_subreq_terminated() in favour of
passing the value in subreq->error.

Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/20241216204124.3752367-9-dhowells@redhat.com
cc: Jeff Layton <jlayton@kernel.org>
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-12-20 22:34:03 +01:00
Ilya Dryomov
18d44c5d06 ceph: allocate sparse_ext map only for sparse reads
If mounted with sparseread option, ceph_direct_read_write() ends up
making an unnecessarily allocation for O_DIRECT writes.

Fixes: 03bc06c7b0bd ("ceph: add new mount option to enable sparse reads")
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Alex Markuze <amarkuze@redhat.com>
2024-12-16 23:25:44 +01:00
Ilya Dryomov
66e0c4f914 ceph: fix memory leak in ceph_direct_read_write()
The bvecs array which is allocated in iter_get_bvecs_alloc() is leaked
and pages remain pinned if ceph_alloc_sparse_ext_map() fails.

There is no need to delay the allocation of sparse_ext map until after
the bvecs array is set up, so fix this by moving sparse_ext allocation
a bit earlier.  Also, make a similar adjustment in __ceph_sync_read()
for consistency (a leak of the same kind in __ceph_sync_read() has been
addressed differently).

Cc: stable@vger.kernel.org
Fixes: 03bc06c7b0bd ("ceph: add new mount option to enable sparse reads")
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Alex Markuze <amarkuze@redhat.com>
2024-12-16 23:25:44 +01:00
Alex Markuze
9abee47580 ceph: improve error handling and short/overflow-read logic in __ceph_sync_read()
This patch refines the read logic in __ceph_sync_read() to ensure more
predictable and efficient behavior in various edge cases.

- Return early if the requested read length is zero or if the file size
  (`i_size`) is zero.
- Initialize the index variable (`idx`) where needed and reorder some
  code to ensure it is always set before use.
- Improve error handling by checking for negative return values earlier.
- Remove redundant encrypted file checks after failures. Only attempt
  filesystem-level decryption if the read succeeded.
- Simplify leftover calculations to correctly handle cases where the
  read extends beyond the end of the file or stops short.  This can be
  hit by continuously reading a file while, on another client, we keep
  truncating and writing new data into it.
- This resolves multiple issues caused by integer and consequent buffer
  overflow (`pages` array being accessed beyond `num_pages`):
  - https://tracker.ceph.com/issues/67524
  - https://tracker.ceph.com/issues/68980
  - https://tracker.ceph.com/issues/68981

Cc: stable@vger.kernel.org
Fixes: 1065da21e5df ("ceph: stop copying to iter at EOF on sync reads")
Reported-by: Luis Henriques (SUSE) <luis.henriques@linux.dev>
Signed-off-by: Alex Markuze <amarkuze@redhat.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2024-12-16 23:25:43 +01:00
Ilya Dryomov
12eb22a5a6 ceph: validate snapdirname option length when mounting
It becomes a path component, so it shouldn't exceed NAME_MAX
characters.  This was hardened in commit c152737be22b ("ceph: Use
strscpy() instead of strcpy() in __get_snap_name()"), but no actual
check was put in place.

Cc: stable@vger.kernel.org
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Alex Markuze <amarkuze@redhat.com>
2024-12-16 23:25:43 +01:00
Max Kellermann
550f7ca98e ceph: give up on paths longer than PATH_MAX
If the full path to be built by ceph_mdsc_build_path() happens to be
longer than PATH_MAX, then this function will enter an endless (retry)
loop, effectively blocking the whole task.  Most of the machine
becomes unusable, making this a very simple and effective DoS
vulnerability.

I cannot imagine why this retry was ever implemented, but it seems
rather useless and harmful to me.  Let's remove it and fail with
ENAMETOOLONG instead.

Cc: stable@vger.kernel.org
Reported-by: Dario Weißer <dario@cure53.de>
Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Reviewed-by: Alex Markuze <amarkuze@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2024-12-16 23:25:43 +01:00