[PULL 0/8] Block layer patches

[PULL 0/8] Block layer patches

[Kevin Wolf]

The following changes since commit 80e8f0602168f451a93e71cbb1d59e93d745e62e:

  Merge tag 'bsd-user-misc-2024q2-pull-request' of gitlab.com:bsdimp/qemu into staging (2024-06-09 11:21:55 -0700)

are available in the Git repository at:

  https://repo.or.cz/qemu/kevin.git tags/for-upstream

for you to fetch changes up to 3ab0f063e58ed9224237d69c4211ca83335164c4:

  crypto/block: drop qcrypto_block_open() n_threads argument (2024-06-10 11:05:43 +0200)

----------------------------------------------------------------
Block layer patches

- crypto: Fix crash when used with multiqueue devices
- linux-aio: add IO_CMD_FDSYNC command support
- copy-before-write: Avoid integer overflows for timeout > 4s
- Fix crash with QMP block_resize and iothreads
- qemu-io: add cvtnum() error handling for zone commands
- Code cleanup

----------------------------------------------------------------
Denis V. Lunev via (1):
      block: drop force_dup parameter of raw_reconfigure_getfd()

Fiona Ebner (1):
      block/copy-before-write: use uint64_t for timeout in nanoseconds

Prasad J Pandit (1):
      linux-aio: add IO_CMD_FDSYNC command support

Stefan Hajnoczi (5):
      Revert "monitor: use aio_co_reschedule_self()"
      aio: warn about iohandler_ctx special casing
      qemu-io: add cvtnum() error handling for zone commands
      block/crypto: create ciphers on demand
      crypto/block: drop qcrypto_block_open() n_threads argument

 crypto/blockpriv.h             |  13 +++--
 include/block/aio.h            |   6 +++
 include/block/raw-aio.h        |   1 +
 include/crypto/block.h         |   2 -
 block/copy-before-write.c      |   2 +-
 block/crypto.c                 |   1 -
 block/file-posix.c             |  17 ++++--
 block/linux-aio.c              |  21 +++++++-
 block/qcow.c                   |   2 +-
 block/qcow2.c                  |   5 +-
 crypto/block-luks.c            |   4 +-
 crypto/block-qcow.c            |   8 ++-
 crypto/block.c                 | 114 ++++++++++++++++++++++++-----------------
 qapi/qmp-dispatch.c            |   7 ++-
 qemu-io-cmds.c                 |  48 ++++++++++++++++-
 tests/unit/test-crypto-block.c |   4 --
 16 files changed, 176 insertions(+), 79 deletions(-)

[PULL 1/8] block: drop force_dup parameter of raw_reconfigure_getfd()

[Kevin Wolf]

From: "Denis V. Lunev via" <qemu-block@nongnu.org>

Since commit 72373e40fbc, this parameter is always passed as 'false'
from the caller.

Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Andrey Zhadchenko <andrey.zhadchenko@virtuozzo.com>
CC: Kevin Wolf <kwolf@redhat.com>
CC: Hanna Reitz <hreitz@redhat.com>
Message-ID: <20240430170213.148558-1-den@openvz.org>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
 block/file-posix.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/block/file-posix.c b/block/file-posix.c
index 35684f7e21..5c46938936 100644
--- a/block/file-posix.c
+++ b/block/file-posix.c
@@ -1039,8 +1039,7 @@ static int fcntl_setfl(int fd, int flag)
 }
 
 static int raw_reconfigure_getfd(BlockDriverState *bs, int flags,
-                                 int *open_flags, uint64_t perm, bool force_dup,
-                                 Error **errp)
+                                 int *open_flags, uint64_t perm, Error **errp)
 {
     BDRVRawState *s = bs->opaque;
     int fd = -1;
@@ -1068,7 +1067,7 @@ static int raw_reconfigure_getfd(BlockDriverState *bs, int flags,
     assert((s->open_flags & O_ASYNC) == 0);
 #endif
 
-    if (!force_dup && *open_flags == s->open_flags) {
+    if (*open_flags == s->open_flags) {
         /* We're lucky, the existing fd is fine */
         return s->fd;
     }
@@ -3748,8 +3747,7 @@ static int raw_check_perm(BlockDriverState *bs, uint64_t perm, uint64_t shared,
     int ret;
 
     /* We may need a new fd if auto-read-only switches the mode */
-    ret = raw_reconfigure_getfd(bs, input_flags, &open_flags, perm,
-                                false, errp);
+    ret = raw_reconfigure_getfd(bs, input_flags, &open_flags, perm, errp);
     if (ret < 0) {
         return ret;
     } else if (ret != s->fd) {
-- 
2.45.2

[PULL 2/8] Revert "monitor: use aio_co_reschedule_self()"

[Kevin Wolf]

From: Stefan Hajnoczi <stefanha@redhat.com>

Commit 1f25c172f837 ("monitor: use aio_co_reschedule_self()") was a code
cleanup that uses aio_co_reschedule_self() instead of open coding
coroutine rescheduling.

Bug RHEL-34618 was reported and Kevin Wolf <kwolf@redhat.com> identified
the root cause. I missed that aio_co_reschedule_self() ->
qemu_get_current_aio_context() only knows about
qemu_aio_context/IOThread AioContexts and not about iohandler_ctx. It
does not function correctly when going back from the iohandler_ctx to
qemu_aio_context.

Go back to open coding the AioContext transitions to avoid this bug.

This reverts commit 1f25c172f83704e350c0829438d832384084a74d.

Cc: qemu-stable@nongnu.org
Buglink: https://issues.redhat.com/browse/RHEL-34618
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-ID: <20240506190622.56095-2-stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
 qapi/qmp-dispatch.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/qapi/qmp-dispatch.c b/qapi/qmp-dispatch.c
index f3488afeef..176b549473 100644
--- a/qapi/qmp-dispatch.c
+++ b/qapi/qmp-dispatch.c
@@ -212,7 +212,8 @@ QDict *coroutine_mixed_fn qmp_dispatch(const QmpCommandList *cmds, QObject *requ
              * executing the command handler so that it can make progress if it
              * involves an AIO_WAIT_WHILE().
              */
-            aio_co_reschedule_self(qemu_get_aio_context());
+            aio_co_schedule(qemu_get_aio_context(), qemu_coroutine_self());
+            qemu_coroutine_yield();
         }
 
         monitor_set_cur(qemu_coroutine_self(), cur_mon);
@@ -226,7 +227,9 @@ QDict *coroutine_mixed_fn qmp_dispatch(const QmpCommandList *cmds, QObject *requ
              * Move back to iohandler_ctx so that nested event loops for
              * qemu_aio_context don't start new monitor commands.
              */
-            aio_co_reschedule_self(iohandler_get_aio_context());
+            aio_co_schedule(iohandler_get_aio_context(),
+                            qemu_coroutine_self());
+            qemu_coroutine_yield();
         }
     } else {
        /*
-- 
2.45.2

[PULL 3/8] aio: warn about iohandler_ctx special casing

[Kevin Wolf]

From: Stefan Hajnoczi <stefanha@redhat.com>

The main loop has two AioContexts: qemu_aio_context and iohandler_ctx.
The main loop runs them both, but nested aio_poll() calls on
qemu_aio_context exclude iohandler_ctx.

Which one should qemu_get_current_aio_context() return when called from
the main loop? Document that it's always qemu_aio_context.

This has subtle effects on functions that use
qemu_get_current_aio_context(). For example, aio_co_reschedule_self()
does not work when moving from iohandler_ctx to qemu_aio_context because
qemu_get_current_aio_context() does not differentiate these two
AioContexts.

Document this in order to reduce the chance of future bugs.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-ID: <20240506190622.56095-3-stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
 include/block/aio.h | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/include/block/aio.h b/include/block/aio.h
index 8378553eb9..4ee81936ed 100644
--- a/include/block/aio.h
+++ b/include/block/aio.h
@@ -629,6 +629,9 @@ void aio_co_schedule(AioContext *ctx, Coroutine *co);
  *
  * Move the currently running coroutine to new_ctx. If the coroutine is already
  * running in new_ctx, do nothing.
+ *
+ * Note that this function cannot reschedule from iohandler_ctx to
+ * qemu_aio_context.
  */
 void coroutine_fn aio_co_reschedule_self(AioContext *new_ctx);
 
@@ -661,6 +664,9 @@ void aio_co_enter(AioContext *ctx, Coroutine *co);
  * If called from an IOThread this will be the IOThread's AioContext.  If
  * called from the main thread or with the "big QEMU lock" taken it
  * will be the main loop AioContext.
+ *
+ * Note that the return value is never the main loop's iohandler_ctx and the
+ * return value is the main loop AioContext instead.
  */
 AioContext *qemu_get_current_aio_context(void);
 
-- 
2.45.2

[PULL 4/8] qemu-io: add cvtnum() error handling for zone commands

[Kevin Wolf]

From: Stefan Hajnoczi <stefanha@redhat.com>

cvtnum() parses positive int64_t values and returns a negative errno on
failure. Print errors and return early when cvtnum() fails.

While we're at it, also reject nr_zones values greater or equal to 2^32
since they cannot be represented.

Reported-by: Peter Maydell <peter.maydell@linaro.org>
Cc: Sam Li <faithilikerun@gmail.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-ID: <20240507180558.377233-1-stefanha@redhat.com>
Reviewed-by: Sam Li <faithilikerun@gmail.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
 qemu-io-cmds.c | 48 +++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 47 insertions(+), 1 deletion(-)

diff --git a/qemu-io-cmds.c b/qemu-io-cmds.c
index f5d7202a13..e2fab57183 100644
--- a/qemu-io-cmds.c
+++ b/qemu-io-cmds.c
@@ -1739,12 +1739,26 @@ static int zone_report_f(BlockBackend *blk, int argc, char **argv)
 {
     int ret;
     int64_t offset;
+    int64_t val;
     unsigned int nr_zones;
 
     ++optind;
     offset = cvtnum(argv[optind]);
+    if (offset < 0) {
+        print_cvtnum_err(offset, argv[optind]);
+        return offset;
+    }
     ++optind;
-    nr_zones = cvtnum(argv[optind]);
+    val = cvtnum(argv[optind]);
+    if (val < 0) {
+        print_cvtnum_err(val, argv[optind]);
+        return val;
+    }
+    if (val > UINT_MAX) {
+        printf("Number of zones must be less than 2^32\n");
+        return -ERANGE;
+    }
+    nr_zones = val;
 
     g_autofree BlockZoneDescriptor *zones = NULL;
     zones = g_new(BlockZoneDescriptor, nr_zones);
@@ -1780,8 +1794,16 @@ static int zone_open_f(BlockBackend *blk, int argc, char **argv)
     int64_t offset, len;
     ++optind;
     offset = cvtnum(argv[optind]);
+    if (offset < 0) {
+        print_cvtnum_err(offset, argv[optind]);
+        return offset;
+    }
     ++optind;
     len = cvtnum(argv[optind]);
+    if (len < 0) {
+        print_cvtnum_err(len, argv[optind]);
+        return len;
+    }
     ret = blk_zone_mgmt(blk, BLK_ZO_OPEN, offset, len);
     if (ret < 0) {
         printf("zone open failed: %s\n", strerror(-ret));
@@ -1805,8 +1827,16 @@ static int zone_close_f(BlockBackend *blk, int argc, char **argv)
     int64_t offset, len;
     ++optind;
     offset = cvtnum(argv[optind]);
+    if (offset < 0) {
+        print_cvtnum_err(offset, argv[optind]);
+        return offset;
+    }
     ++optind;
     len = cvtnum(argv[optind]);
+    if (len < 0) {
+        print_cvtnum_err(len, argv[optind]);
+        return len;
+    }
     ret = blk_zone_mgmt(blk, BLK_ZO_CLOSE, offset, len);
     if (ret < 0) {
         printf("zone close failed: %s\n", strerror(-ret));
@@ -1830,8 +1860,16 @@ static int zone_finish_f(BlockBackend *blk, int argc, char **argv)
     int64_t offset, len;
     ++optind;
     offset = cvtnum(argv[optind]);
+    if (offset < 0) {
+        print_cvtnum_err(offset, argv[optind]);
+        return offset;
+    }
     ++optind;
     len = cvtnum(argv[optind]);
+    if (len < 0) {
+        print_cvtnum_err(len, argv[optind]);
+        return len;
+    }
     ret = blk_zone_mgmt(blk, BLK_ZO_FINISH, offset, len);
     if (ret < 0) {
         printf("zone finish failed: %s\n", strerror(-ret));
@@ -1855,8 +1893,16 @@ static int zone_reset_f(BlockBackend *blk, int argc, char **argv)
     int64_t offset, len;
     ++optind;
     offset = cvtnum(argv[optind]);
+    if (offset < 0) {
+        print_cvtnum_err(offset, argv[optind]);
+        return offset;
+    }
     ++optind;
     len = cvtnum(argv[optind]);
+    if (len < 0) {
+        print_cvtnum_err(len, argv[optind]);
+        return len;
+    }
     ret = blk_zone_mgmt(blk, BLK_ZO_RESET, offset, len);
     if (ret < 0) {
         printf("zone reset failed: %s\n", strerror(-ret));
-- 
2.45.2

[PULL 5/8] block/copy-before-write: use uint64_t for timeout in nanoseconds

[Kevin Wolf]

From: Fiona Ebner <f.ebner@proxmox.com>

rather than the uint32_t for which the maximum is slightly more than 4
seconds and larger values would overflow. The QAPI interface allows
specifying the number of seconds, so only values 0 to 4 are safe right
now, other values lead to a much lower timeout than a user expects.

The block_copy() call where this is used already takes a uint64_t for
the timeout, so no change required there.

Fixes: 6db7fd1ca9 ("block/copy-before-write: implement cbw-timeout option")
Reported-by: Friedrich Weber <f.weber@proxmox.com>
Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>
Message-ID: <20240429141934.442154-1-f.ebner@proxmox.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
 block/copy-before-write.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/block/copy-before-write.c b/block/copy-before-write.c
index cd65524e26..853e01a1eb 100644
--- a/block/copy-before-write.c
+++ b/block/copy-before-write.c
@@ -43,7 +43,7 @@ typedef struct BDRVCopyBeforeWriteState {
     BlockCopyState *bcs;
     BdrvChild *target;
     OnCbwError on_cbw_error;
-    uint32_t cbw_timeout_ns;
+    uint64_t cbw_timeout_ns;
     bool discard_source;
 
     /*
-- 
2.45.2

[PULL 6/8] linux-aio: add IO_CMD_FDSYNC command support

[Kevin Wolf]

From: Prasad Pandit <pjp@fedoraproject.org>

Libaio defines IO_CMD_FDSYNC command to sync all outstanding
asynchronous I/O operations, by flushing out file data to the
disk storage. Enable linux-aio to submit such aio request.

When using aio=native without fdsync() support, QEMU creates
pthreads, and destroying these pthreads results in TLB flushes.
In a real-time guest environment, TLB flushes cause a latency
spike. This patch helps to avoid such spikes.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Prasad Pandit <pjp@fedoraproject.org>
Message-ID: <20240425070412.37248-1-ppandit@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
 include/block/raw-aio.h |  1 +
 block/file-posix.c      |  9 +++++++++
 block/linux-aio.c       | 21 ++++++++++++++++++++-
 3 files changed, 30 insertions(+), 1 deletion(-)

diff --git a/include/block/raw-aio.h b/include/block/raw-aio.h
index 20e000b8ef..626706827f 100644
--- a/include/block/raw-aio.h
+++ b/include/block/raw-aio.h
@@ -60,6 +60,7 @@ void laio_cleanup(LinuxAioState *s);
 int coroutine_fn laio_co_submit(int fd, uint64_t offset, QEMUIOVector *qiov,
                                 int type, uint64_t dev_max_batch);
 
+bool laio_has_fdsync(int);
 void laio_detach_aio_context(LinuxAioState *s, AioContext *old_context);
 void laio_attach_aio_context(LinuxAioState *s, AioContext *new_context);
 #endif
diff --git a/block/file-posix.c b/block/file-posix.c
index 5c46938936..be25e35ff6 100644
--- a/block/file-posix.c
+++ b/block/file-posix.c
@@ -159,6 +159,7 @@ typedef struct BDRVRawState {
     bool has_discard:1;
     bool has_write_zeroes:1;
     bool use_linux_aio:1;
+    bool has_laio_fdsync:1;
     bool use_linux_io_uring:1;
     int page_cache_inconsistent; /* errno from fdatasync failure */
     bool has_fallocate;
@@ -718,6 +719,9 @@ static int raw_open_common(BlockDriverState *bs, QDict *options,
         ret = -EINVAL;
         goto fail;
     }
+    if (s->use_linux_aio) {
+        s->has_laio_fdsync = laio_has_fdsync(s->fd);
+    }
 #else
     if (s->use_linux_aio) {
         error_setg(errp, "aio=native was specified, but is not supported "
@@ -2598,6 +2602,11 @@ static int coroutine_fn raw_co_flush_to_disk(BlockDriverState *bs)
     if (raw_check_linux_io_uring(s)) {
         return luring_co_submit(bs, s->fd, 0, NULL, QEMU_AIO_FLUSH);
     }
+#endif
+#ifdef CONFIG_LINUX_AIO
+    if (s->has_laio_fdsync && raw_check_linux_aio(s)) {
+        return laio_co_submit(s->fd, 0, NULL, QEMU_AIO_FLUSH, 0);
+    }
 #endif
     return raw_thread_pool_submit(handle_aiocb_flush, &acb);
 }
diff --git a/block/linux-aio.c b/block/linux-aio.c
index ec05d946f3..e3b5ec9aba 100644
--- a/block/linux-aio.c
+++ b/block/linux-aio.c
@@ -384,6 +384,9 @@ static int laio_do_submit(int fd, struct qemu_laiocb *laiocb, off_t offset,
     case QEMU_AIO_READ:
         io_prep_preadv(iocbs, fd, qiov->iov, qiov->niov, offset);
         break;
+    case QEMU_AIO_FLUSH:
+        io_prep_fdsync(iocbs, fd);
+        break;
     /* Currently Linux kernel does not support other operations */
     default:
         fprintf(stderr, "%s: invalid AIO request type 0x%x.\n",
@@ -412,7 +415,7 @@ int coroutine_fn laio_co_submit(int fd, uint64_t offset, QEMUIOVector *qiov,
     AioContext *ctx = qemu_get_current_aio_context();
     struct qemu_laiocb laiocb = {
         .co         = qemu_coroutine_self(),
-        .nbytes     = qiov->size,
+        .nbytes     = qiov ? qiov->size : 0,
         .ctx        = aio_get_linux_aio(ctx),
         .ret        = -EINPROGRESS,
         .is_read    = (type == QEMU_AIO_READ),
@@ -486,3 +489,19 @@ void laio_cleanup(LinuxAioState *s)
     }
     g_free(s);
 }
+
+bool laio_has_fdsync(int fd)
+{
+    struct iocb cb;
+    struct iocb *cbs[] = {&cb, NULL};
+
+    io_context_t ctx = 0;
+    io_setup(1, &ctx);
+
+    /* check if host kernel supports IO_CMD_FDSYNC */
+    io_prep_fdsync(&cb, fd);
+    int ret = io_submit(ctx, 1, cbs);
+
+    io_destroy(ctx);
+    return (ret == -EINVAL) ? false : true;
+}
-- 
2.45.2

[PULL 7/8] block/crypto: create ciphers on demand

[Kevin Wolf]

From: Stefan Hajnoczi <stefanha@redhat.com>

Ciphers are pre-allocated by qcrypto_block_init_cipher() depending on
the given number of threads. The -device
virtio-blk-pci,iothread-vq-mapping= feature allows users to assign
multiple IOThreads to a virtio-blk device, but the association between
the virtio-blk device and the block driver happens after the block
driver is already open.

When the number of threads given to qcrypto_block_init_cipher() is
smaller than the actual number of threads at runtime, the
block->n_free_ciphers > 0 assertion in qcrypto_block_pop_cipher() can
fail.

Get rid of qcrypto_block_init_cipher() n_thread's argument and allocate
ciphers on demand.

Reported-by: Qing Wang <qinwang@redhat.com>
Buglink: https://issues.redhat.com/browse/RHEL-36159
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-ID: <20240527155851.892885-2-stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
 crypto/blockpriv.h  |  12 +++--
 crypto/block-luks.c |   3 +-
 crypto/block-qcow.c |   2 +-
 crypto/block.c      | 111 ++++++++++++++++++++++++++------------------
 4 files changed, 78 insertions(+), 50 deletions(-)

diff --git a/crypto/blockpriv.h b/crypto/blockpriv.h
index 836f3b4726..4bf6043d5d 100644
--- a/crypto/blockpriv.h
+++ b/crypto/blockpriv.h
@@ -32,8 +32,14 @@ struct QCryptoBlock {
     const QCryptoBlockDriver *driver;
     void *opaque;
 
-    QCryptoCipher **ciphers;
-    size_t n_ciphers;
+    /* Cipher parameters */
+    QCryptoCipherAlgorithm alg;
+    QCryptoCipherMode mode;
+    uint8_t *key;
+    size_t nkey;
+
+    QCryptoCipher **free_ciphers;
+    size_t max_free_ciphers;
     size_t n_free_ciphers;
     QCryptoIVGen *ivgen;
     QemuMutex mutex;
@@ -130,7 +136,7 @@ int qcrypto_block_init_cipher(QCryptoBlock *block,
                               QCryptoCipherAlgorithm alg,
                               QCryptoCipherMode mode,
                               const uint8_t *key, size_t nkey,
-                              size_t n_threads, Error **errp);
+                              Error **errp);
 
 void qcrypto_block_free_cipher(QCryptoBlock *block);
 
diff --git a/crypto/block-luks.c b/crypto/block-luks.c
index 3ee928fb5a..3357852c0a 100644
--- a/crypto/block-luks.c
+++ b/crypto/block-luks.c
@@ -1262,7 +1262,6 @@ qcrypto_block_luks_open(QCryptoBlock *block,
                                       luks->cipher_mode,
                                       masterkey,
                                       luks->header.master_key_len,
-                                      n_threads,
                                       errp) < 0) {
             goto fail;
         }
@@ -1456,7 +1455,7 @@ qcrypto_block_luks_create(QCryptoBlock *block,
     /* Setup the block device payload encryption objects */
     if (qcrypto_block_init_cipher(block, luks_opts.cipher_alg,
                                   luks_opts.cipher_mode, masterkey,
-                                  luks->header.master_key_len, 1, errp) < 0) {
+                                  luks->header.master_key_len, errp) < 0) {
         goto error;
     }
 
diff --git a/crypto/block-qcow.c b/crypto/block-qcow.c
index 4d7cf36a8f..02305058e3 100644
--- a/crypto/block-qcow.c
+++ b/crypto/block-qcow.c
@@ -75,7 +75,7 @@ qcrypto_block_qcow_init(QCryptoBlock *block,
     ret = qcrypto_block_init_cipher(block, QCRYPTO_CIPHER_ALG_AES_128,
                                     QCRYPTO_CIPHER_MODE_CBC,
                                     keybuf, G_N_ELEMENTS(keybuf),
-                                    n_threads, errp);
+                                    errp);
     if (ret < 0) {
         ret = -ENOTSUP;
         goto fail;
diff --git a/crypto/block.c b/crypto/block.c
index 506ea1d1a3..ba6d1cebc7 100644
--- a/crypto/block.c
+++ b/crypto/block.c
@@ -20,6 +20,7 @@
 
 #include "qemu/osdep.h"
 #include "qapi/error.h"
+#include "qemu/lockable.h"
 #include "blockpriv.h"
 #include "block-qcow.h"
 #include "block-luks.h"
@@ -57,6 +58,8 @@ QCryptoBlock *qcrypto_block_open(QCryptoBlockOpenOptions *options,
 {
     QCryptoBlock *block = g_new0(QCryptoBlock, 1);
 
+    qemu_mutex_init(&block->mutex);
+
     block->format = options->format;
 
     if (options->format >= G_N_ELEMENTS(qcrypto_block_drivers) ||
@@ -76,8 +79,6 @@ QCryptoBlock *qcrypto_block_open(QCryptoBlockOpenOptions *options,
         return NULL;
     }
 
-    qemu_mutex_init(&block->mutex);
-
     return block;
 }
 
@@ -92,6 +93,8 @@ QCryptoBlock *qcrypto_block_create(QCryptoBlockCreateOptions *options,
 {
     QCryptoBlock *block = g_new0(QCryptoBlock, 1);
 
+    qemu_mutex_init(&block->mutex);
+
     block->format = options->format;
 
     if (options->format >= G_N_ELEMENTS(qcrypto_block_drivers) ||
@@ -111,8 +114,6 @@ QCryptoBlock *qcrypto_block_create(QCryptoBlockCreateOptions *options,
         return NULL;
     }
 
-    qemu_mutex_init(&block->mutex);
-
     return block;
 }
 
@@ -227,37 +228,42 @@ QCryptoCipher *qcrypto_block_get_cipher(QCryptoBlock *block)
      * This function is used only in test with one thread (it's safe to skip
      * pop/push interface), so it's enough to assert it here:
      */
-    assert(block->n_ciphers <= 1);
-    return block->ciphers ? block->ciphers[0] : NULL;
+    assert(block->max_free_ciphers <= 1);
+    return block->free_ciphers ? block->free_ciphers[0] : NULL;
 }
 
 
-static QCryptoCipher *qcrypto_block_pop_cipher(QCryptoBlock *block)
+static QCryptoCipher *qcrypto_block_pop_cipher(QCryptoBlock *block,
+                                               Error **errp)
 {
-    QCryptoCipher *cipher;
-
-    qemu_mutex_lock(&block->mutex);
-
-    assert(block->n_free_ciphers > 0);
-    block->n_free_ciphers--;
-    cipher = block->ciphers[block->n_free_ciphers];
-
-    qemu_mutex_unlock(&block->mutex);
+    /* Usually there is a free cipher available */
+    WITH_QEMU_LOCK_GUARD(&block->mutex) {
+        if (block->n_free_ciphers > 0) {
+            block->n_free_ciphers--;
+            return block->free_ciphers[block->n_free_ciphers];
+        }
+    }
 
-    return cipher;
+    /* Otherwise allocate a new cipher */
+    return qcrypto_cipher_new(block->alg, block->mode, block->key,
+                              block->nkey, errp);
 }
 
 
 static void qcrypto_block_push_cipher(QCryptoBlock *block,
                                       QCryptoCipher *cipher)
 {
-    qemu_mutex_lock(&block->mutex);
+    QEMU_LOCK_GUARD(&block->mutex);
 
-    assert(block->n_free_ciphers < block->n_ciphers);
-    block->ciphers[block->n_free_ciphers] = cipher;
-    block->n_free_ciphers++;
+    if (block->n_free_ciphers == block->max_free_ciphers) {
+        block->max_free_ciphers++;
+        block->free_ciphers = g_renew(QCryptoCipher *,
+                                      block->free_ciphers,
+                                      block->max_free_ciphers);
+    }
 
-    qemu_mutex_unlock(&block->mutex);
+    block->free_ciphers[block->n_free_ciphers] = cipher;
+    block->n_free_ciphers++;
 }
 
 
@@ -265,24 +271,31 @@ int qcrypto_block_init_cipher(QCryptoBlock *block,
                               QCryptoCipherAlgorithm alg,
                               QCryptoCipherMode mode,
                               const uint8_t *key, size_t nkey,
-                              size_t n_threads, Error **errp)
+                              Error **errp)
 {
-    size_t i;
+    QCryptoCipher *cipher;
 
-    assert(!block->ciphers && !block->n_ciphers && !block->n_free_ciphers);
+    assert(!block->free_ciphers && !block->max_free_ciphers &&
+           !block->n_free_ciphers);
 
-    block->ciphers = g_new0(QCryptoCipher *, n_threads);
+    /* Stash away cipher parameters for qcrypto_block_pop_cipher() */
+    block->alg = alg;
+    block->mode = mode;
+    block->key = g_memdup2(key, nkey);
+    block->nkey = nkey;
 
-    for (i = 0; i < n_threads; i++) {
-        block->ciphers[i] = qcrypto_cipher_new(alg, mode, key, nkey, errp);
-        if (!block->ciphers[i]) {
-            qcrypto_block_free_cipher(block);
-            return -1;
-        }
-        block->n_ciphers++;
-        block->n_free_ciphers++;
+    /*
+     * Create a new cipher to validate the parameters now. This reduces the
+     * chance of cipher creation failing at I/O time.
+     */
+    cipher = qcrypto_block_pop_cipher(block, errp);
+    if (!cipher) {
+        g_free(block->key);
+        block->key = NULL;
+        return -1;
     }
 
+    qcrypto_block_push_cipher(block, cipher);
     return 0;
 }
 
@@ -291,19 +304,23 @@ void qcrypto_block_free_cipher(QCryptoBlock *block)
 {
     size_t i;
 
-    if (!block->ciphers) {
+    g_free(block->key);
+    block->key = NULL;
+
+    if (!block->free_ciphers) {
         return;
     }
 
-    assert(block->n_ciphers == block->n_free_ciphers);
+    /* All popped ciphers were eventually pushed back */
+    assert(block->n_free_ciphers == block->max_free_ciphers);
 
-    for (i = 0; i < block->n_ciphers; i++) {
-        qcrypto_cipher_free(block->ciphers[i]);
+    for (i = 0; i < block->max_free_ciphers; i++) {
+        qcrypto_cipher_free(block->free_ciphers[i]);
     }
 
-    g_free(block->ciphers);
-    block->ciphers = NULL;
-    block->n_ciphers = block->n_free_ciphers = 0;
+    g_free(block->free_ciphers);
+    block->free_ciphers = NULL;
+    block->max_free_ciphers = block->n_free_ciphers = 0;
 }
 
 QCryptoIVGen *qcrypto_block_get_ivgen(QCryptoBlock *block)
@@ -311,7 +328,7 @@ QCryptoIVGen *qcrypto_block_get_ivgen(QCryptoBlock *block)
     /* ivgen should be accessed under mutex. However, this function is used only
      * in test with one thread, so it's enough to assert it here:
      */
-    assert(block->n_ciphers <= 1);
+    assert(block->max_free_ciphers <= 1);
     return block->ivgen;
 }
 
@@ -446,7 +463,10 @@ int qcrypto_block_decrypt_helper(QCryptoBlock *block,
                                  Error **errp)
 {
     int ret;
-    QCryptoCipher *cipher = qcrypto_block_pop_cipher(block);
+    QCryptoCipher *cipher = qcrypto_block_pop_cipher(block, errp);
+    if (!cipher) {
+        return -1;
+    }
 
     ret = do_qcrypto_block_cipher_encdec(cipher, block->niv, block->ivgen,
                                          &block->mutex, sectorsize, offset, buf,
@@ -465,7 +485,10 @@ int qcrypto_block_encrypt_helper(QCryptoBlock *block,
                                  Error **errp)
 {
     int ret;
-    QCryptoCipher *cipher = qcrypto_block_pop_cipher(block);
+    QCryptoCipher *cipher = qcrypto_block_pop_cipher(block, errp);
+    if (!cipher) {
+        return -1;
+    }
 
     ret = do_qcrypto_block_cipher_encdec(cipher, block->niv, block->ivgen,
                                          &block->mutex, sectorsize, offset, buf,
-- 
2.45.2

[PULL 8/8] crypto/block: drop qcrypto_block_open() n_threads argument

[Kevin Wolf]

From: Stefan Hajnoczi <stefanha@redhat.com>

The n_threads argument is no longer used since the previous commit.
Remove it.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-ID: <20240527155851.892885-3-stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
 crypto/blockpriv.h             | 1 -
 include/crypto/block.h         | 2 --
 block/crypto.c                 | 1 -
 block/qcow.c                   | 2 +-
 block/qcow2.c                  | 5 ++---
 crypto/block-luks.c            | 1 -
 crypto/block-qcow.c            | 6 ++----
 crypto/block.c                 | 3 +--
 tests/unit/test-crypto-block.c | 4 ----
 9 files changed, 6 insertions(+), 19 deletions(-)

diff --git a/crypto/blockpriv.h b/crypto/blockpriv.h
index 4bf6043d5d..b8f77cb5eb 100644
--- a/crypto/blockpriv.h
+++ b/crypto/blockpriv.h
@@ -59,7 +59,6 @@ struct QCryptoBlockDriver {
                 QCryptoBlockReadFunc readfunc,
                 void *opaque,
                 unsigned int flags,
-                size_t n_threads,
                 Error **errp);
 
     int (*create)(QCryptoBlock *block,
diff --git a/include/crypto/block.h b/include/crypto/block.h
index 92e823c9f2..5b5d039800 100644
--- a/include/crypto/block.h
+++ b/include/crypto/block.h
@@ -76,7 +76,6 @@ typedef enum {
  * @readfunc: callback for reading data from the volume
  * @opaque: data to pass to @readfunc
  * @flags: bitmask of QCryptoBlockOpenFlags values
- * @n_threads: allow concurrent I/O from up to @n_threads threads
  * @errp: pointer to a NULL-initialized error object
  *
  * Create a new block encryption object for an existing
@@ -113,7 +112,6 @@ QCryptoBlock *qcrypto_block_open(QCryptoBlockOpenOptions *options,
                                  QCryptoBlockReadFunc readfunc,
                                  void *opaque,
                                  unsigned int flags,
-                                 size_t n_threads,
                                  Error **errp);
 
 typedef enum {
diff --git a/block/crypto.c b/block/crypto.c
index 21eed909c1..4eed3ffa6a 100644
--- a/block/crypto.c
+++ b/block/crypto.c
@@ -363,7 +363,6 @@ static int block_crypto_open_generic(QCryptoBlockFormat format,
                                        block_crypto_read_func,
                                        bs,
                                        cflags,
-                                       1,
                                        errp);
 
     if (!crypto->block) {
diff --git a/block/qcow.c b/block/qcow.c
index ca8e1d5ec8..c2f89db055 100644
--- a/block/qcow.c
+++ b/block/qcow.c
@@ -211,7 +211,7 @@ static int qcow_open(BlockDriverState *bs, QDict *options, int flags,
                 cflags |= QCRYPTO_BLOCK_OPEN_NO_IO;
             }
             s->crypto = qcrypto_block_open(crypto_opts, "encrypt.",
-                                           NULL, NULL, cflags, 1, errp);
+                                           NULL, NULL, cflags, errp);
             if (!s->crypto) {
                 ret = -EINVAL;
                 goto fail;
diff --git a/block/qcow2.c b/block/qcow2.c
index 956128b409..10883a2494 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -321,7 +321,7 @@ qcow2_read_extensions(BlockDriverState *bs, uint64_t start_offset,
             }
             s->crypto = qcrypto_block_open(s->crypto_opts, "encrypt.",
                                            qcow2_crypto_hdr_read_func,
-                                           bs, cflags, QCOW2_MAX_THREADS, errp);
+                                           bs, cflags, errp);
             if (!s->crypto) {
                 return -EINVAL;
             }
@@ -1701,8 +1701,7 @@ qcow2_do_open(BlockDriverState *bs, QDict *options, int flags,
                 cflags |= QCRYPTO_BLOCK_OPEN_NO_IO;
             }
             s->crypto = qcrypto_block_open(s->crypto_opts, "encrypt.",
-                                           NULL, NULL, cflags,
-                                           QCOW2_MAX_THREADS, errp);
+                                           NULL, NULL, cflags, errp);
             if (!s->crypto) {
                 ret = -EINVAL;
                 goto fail;
diff --git a/crypto/block-luks.c b/crypto/block-luks.c
index 3357852c0a..5b777c15d3 100644
--- a/crypto/block-luks.c
+++ b/crypto/block-luks.c
@@ -1189,7 +1189,6 @@ qcrypto_block_luks_open(QCryptoBlock *block,
                         QCryptoBlockReadFunc readfunc,
                         void *opaque,
                         unsigned int flags,
-                        size_t n_threads,
                         Error **errp)
 {
     QCryptoBlockLUKS *luks = NULL;
diff --git a/crypto/block-qcow.c b/crypto/block-qcow.c
index 02305058e3..42e9556e42 100644
--- a/crypto/block-qcow.c
+++ b/crypto/block-qcow.c
@@ -44,7 +44,6 @@ qcrypto_block_qcow_has_format(const uint8_t *buf G_GNUC_UNUSED,
 static int
 qcrypto_block_qcow_init(QCryptoBlock *block,
                         const char *keysecret,
-                        size_t n_threads,
                         Error **errp)
 {
     char *password;
@@ -100,7 +99,6 @@ qcrypto_block_qcow_open(QCryptoBlock *block,
                         QCryptoBlockReadFunc readfunc G_GNUC_UNUSED,
                         void *opaque G_GNUC_UNUSED,
                         unsigned int flags,
-                        size_t n_threads,
                         Error **errp)
 {
     if (flags & QCRYPTO_BLOCK_OPEN_NO_IO) {
@@ -115,7 +113,7 @@ qcrypto_block_qcow_open(QCryptoBlock *block,
             return -1;
         }
         return qcrypto_block_qcow_init(block, options->u.qcow.key_secret,
-                                       n_threads, errp);
+                                       errp);
     }
 }
 
@@ -135,7 +133,7 @@ qcrypto_block_qcow_create(QCryptoBlock *block,
         return -1;
     }
     /* QCow2 has no special header, since everything is hardwired */
-    return qcrypto_block_qcow_init(block, options->u.qcow.key_secret, 1, errp);
+    return qcrypto_block_qcow_init(block, options->u.qcow.key_secret, errp);
 }
 
 
diff --git a/crypto/block.c b/crypto/block.c
index ba6d1cebc7..3bcc4270c3 100644
--- a/crypto/block.c
+++ b/crypto/block.c
@@ -53,7 +53,6 @@ QCryptoBlock *qcrypto_block_open(QCryptoBlockOpenOptions *options,
                                  QCryptoBlockReadFunc readfunc,
                                  void *opaque,
                                  unsigned int flags,
-                                 size_t n_threads,
                                  Error **errp)
 {
     QCryptoBlock *block = g_new0(QCryptoBlock, 1);
@@ -73,7 +72,7 @@ QCryptoBlock *qcrypto_block_open(QCryptoBlockOpenOptions *options,
     block->driver = qcrypto_block_drivers[options->format];
 
     if (block->driver->open(block, options, optprefix,
-                            readfunc, opaque, flags, n_threads, errp) < 0)
+                            readfunc, opaque, flags, errp) < 0)
     {
         g_free(block);
         return NULL;
diff --git a/tests/unit/test-crypto-block.c b/tests/unit/test-crypto-block.c
index 6cfc817a92..42cfab6067 100644
--- a/tests/unit/test-crypto-block.c
+++ b/tests/unit/test-crypto-block.c
@@ -303,7 +303,6 @@ static void test_block(gconstpointer opaque)
                              test_block_read_func,
                              &header,
                              0,
-                             1,
                              NULL);
     g_assert(blk == NULL);
 
@@ -312,7 +311,6 @@ static void test_block(gconstpointer opaque)
                              test_block_read_func,
                              &header,
                              QCRYPTO_BLOCK_OPEN_NO_IO,
-                             1,
                              &error_abort);
 
     g_assert(qcrypto_block_get_cipher(blk) == NULL);
@@ -327,7 +325,6 @@ static void test_block(gconstpointer opaque)
                              test_block_read_func,
                              &header,
                              0,
-                             1,
                              &error_abort);
     g_assert(blk);
 
@@ -384,7 +381,6 @@ test_luks_bad_header(gconstpointer data)
                              test_block_read_func,
                              &buf,
                              0,
-                             1,
                              &err);
     g_assert(!blk);
     g_assert(err);
-- 
2.45.2

Re: [PULL 0/8] Block layer patches

[Richard Henderson]

On 6/11/24 10:36, Kevin Wolf wrote:
> The following changes since commit 80e8f0602168f451a93e71cbb1d59e93d745e62e:
> 
>    Merge tag 'bsd-user-misc-2024q2-pull-request' of gitlab.com:bsdimp/qemu into staging (2024-06-09 11:21:55 -0700)
> 
> are available in the Git repository at:
> 
>    https://repo.or.cz/qemu/kevin.git  tags/for-upstream
> 
> for you to fetch changes up to 3ab0f063e58ed9224237d69c4211ca83335164c4:
> 
>    crypto/block: drop qcrypto_block_open() n_threads argument (2024-06-10 11:05:43 +0200)
> 
> ----------------------------------------------------------------
> Block layer patches
> 
> - crypto: Fix crash when used with multiqueue devices
> - linux-aio: add IO_CMD_FDSYNC command support
> - copy-before-write: Avoid integer overflows for timeout > 4s
> - Fix crash with QMP block_resize and iothreads
> - qemu-io: add cvtnum() error handling for zone commands
> - Code cleanup

Applied, thanks.  Please update https://wiki.qemu.org/ChangeLog/9.1 as appropriate.


r~