[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[PATCH 1/5] crypto: perform permission checks under BQL
From: |
Emanuele Giuseppe Esposito |
Subject: |
[PATCH 1/5] crypto: perform permission checks under BQL |
Date: |
Wed, 9 Feb 2022 05:54:48 -0500 |
Move the permission API calls into driver-specific callbacks
that always run under BQL. In this case, bdrv_crypto_luks
needs to perform permission checks before and after
qcrypto_block_amend_options(). The problem is that the caller,
block_crypto_amend_options_generic_luks(), can also run in I/O
from .bdrv_co_amend(). This does not comply with Global State-I/O API split,
as permissions API must always run under BQL.
Firstly, introduce .bdrv_amend_pre_run() and .bdrv_amend_clean()
callbacks. These two callbacks are guaranteed to be invoked under
BQL, respectively before and after .bdrv_co_amend().
They take care of performing the permission checks
in the same way as they are currently done before and after
qcrypto_block_amend_options().
These callbacks are in preparation for next patch, where we
delete the original permission check. Right now they just add redundant
control.
Then, call .bdrv_amend_pre_run() before job_start in
qmp_x_blockdev_amend(), so that it will be run before the job coroutine
is created and stay in the main loop.
As a cleanup, use JobDriver's .clean() callback to call
.bdrv_amend_clean(), and run amend-specific cleanup callbacks under BQL.
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
---
block/amend.c | 24 ++++++++++++++++++++++++
block/crypto.c | 27 +++++++++++++++++++++++++++
include/block/block_int.h | 14 ++++++++++++++
3 files changed, 65 insertions(+)
diff --git a/block/amend.c b/block/amend.c
index 392df9ef83..329bca53dc 100644
--- a/block/amend.c
+++ b/block/amend.c
@@ -53,10 +53,29 @@ static int coroutine_fn blockdev_amend_run(Job *job, Error
**errp)
return ret;
}
+static int blockdev_amend_pre_run(BlockdevAmendJob *s, Error **errp)
+{
+ if (s->bs->drv->bdrv_amend_pre_run) {
+ return s->bs->drv->bdrv_amend_pre_run(s->bs, errp);
+ }
+
+ return 0;
+}
+
+static void blockdev_amend_clean(Job *job)
+{
+ BlockdevAmendJob *s = container_of(job, BlockdevAmendJob, common);
+
+ if (s->bs->drv->bdrv_amend_clean) {
+ s->bs->drv->bdrv_amend_clean(s->bs);
+ }
+}
+
static const JobDriver blockdev_amend_job_driver = {
.instance_size = sizeof(BlockdevAmendJob),
.job_type = JOB_TYPE_AMEND,
.run = blockdev_amend_run,
+ .clean = blockdev_amend_clean,
};
void qmp_x_blockdev_amend(const char *job_id,
@@ -113,5 +132,10 @@ void qmp_x_blockdev_amend(const char *job_id,
s->bs = bs,
s->opts = QAPI_CLONE(BlockdevAmendOptions, options),
s->force = has_force ? force : false;
+
+ if (blockdev_amend_pre_run(s, errp)) {
+ return;
+ }
+
job_start(&s->common);
}
diff --git a/block/crypto.c b/block/crypto.c
index c8ba4681e2..59f768ea8d 100644
--- a/block/crypto.c
+++ b/block/crypto.c
@@ -777,6 +777,31 @@ block_crypto_get_specific_info_luks(BlockDriverState *bs,
Error **errp)
return spec_info;
}
+static int
+block_crypto_amend_prepare(BlockDriverState *bs, Error **errp)
+{
+ BlockCrypto *crypto = bs->opaque;
+
+ /* apply for exclusive read/write permissions to the underlying file*/
+ crypto->updating_keys = true;
+ return bdrv_child_refresh_perms(bs, bs->file, errp);
+}
+
+static void
+block_crypto_amend_cleanup(BlockDriverState *bs)
+{
+ BlockCrypto *crypto = bs->opaque;
+ Error *errp = NULL;
+
+ /* release exclusive read/write permissions to the underlying file*/
+ crypto->updating_keys = false;
+ bdrv_child_refresh_perms(bs, bs->file, &errp);
+
+ if (errp) {
+ error_report_err(errp);
+ }
+}
+
static int
block_crypto_amend_options_generic_luks(BlockDriverState *bs,
QCryptoBlockAmendOptions
*amend_options,
@@ -931,6 +956,8 @@ static BlockDriver bdrv_crypto_luks = {
.bdrv_get_specific_info = block_crypto_get_specific_info_luks,
.bdrv_amend_options = block_crypto_amend_options_luks,
.bdrv_co_amend = block_crypto_co_amend_luks,
+ .bdrv_amend_pre_run = block_crypto_amend_prepare,
+ .bdrv_amend_clean = block_crypto_amend_cleanup,
.is_format = true,
diff --git a/include/block/block_int.h b/include/block/block_int.h
index 27008cfb22..31bd788919 100644
--- a/include/block/block_int.h
+++ b/include/block/block_int.h
@@ -124,6 +124,20 @@ struct BlockDriver {
* on those children.
*/
bool is_format;
+
+ /*
+ * This function is invoked under BQL before .bdrv_co_amend()
+ * (which in contrast does not necessarily run under the BQL)
+ * to allow driver-specific initialization code that requires
+ * the BQL, like setting up specific permission flags.
+ */
+ int (*bdrv_amend_pre_run)(BlockDriverState *bs, Error **errp);
+ /*
+ * This function is invoked under BQL after .bdrv_co_amend()
+ * to allow cleaning up what was done in .bdrv_amend_pre_run().
+ */
+ void (*bdrv_amend_clean)(BlockDriverState *bs);
+
/*
* Return true if @to_replace can be replaced by a BDS with the
* same data as @bs without it affecting @bs's behavior (that is,
--
2.31.1
- [PATCH 0/5] block layer: permission API refactoring in preparation, Emanuele Giuseppe Esposito, 2022/02/09
- [PATCH 2/5] crypto: distinguish between main loop and I/O in block_crypto_amend_options_generic_luks, Emanuele Giuseppe Esposito, 2022/02/09
- [PATCH 5/5] block: move BQL logic of bdrv_co_invalidate_cache in bdrv_activate, Emanuele Giuseppe Esposito, 2022/02/09
- [PATCH 3/5] block: introduce bdrv_activate, Emanuele Giuseppe Esposito, 2022/02/09
- [PATCH 1/5] crypto: perform permission checks under BQL,
Emanuele Giuseppe Esposito <=
- [PATCH 4/5] block: rename bdrv_invalidate_cache_all, blk_invalidate_cache and test_sync_op_invalidate_cache, Emanuele Giuseppe Esposito, 2022/02/09