Now that all bottom halves and callbacks take care of taking the
AioContext lock, we can migrate some users away from it and to a
specific QemuMutex or CoMutex.
Protect libnfs calls with a QemuMutex. Callbacks are invoked
using bottom halves, so we don't even have to drop it around
callback invocations.
Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
---
block/nfs.c | 23 +++++++++++++++++++----
1 file changed, 19 insertions(+), 4 deletions(-)
diff --git a/block/nfs.c b/block/nfs.c
index 08b43dd..3ee3275 100644
--- a/block/nfs.c
+++ b/block/nfs.c
@@ -54,6 +54,7 @@ typedef struct NFSClient {
int events;
bool has_zero_init;
AioContext *aio_context;
+ QemuMutex mutex;
blkcnt_t st_blocks;
bool cache_used;
NFSServer *server;
@@ -191,6 +192,7 @@ static void nfs_parse_filename(const char *filename, QDict
*options,
static void nfs_process_read(void *arg);
static void nfs_process_write(void *arg);
+/* Called with QemuMutex held. */
static void nfs_set_events(NFSClient *client)
{
int ev = nfs_which_events(client->context);
@@ -209,20 +211,20 @@ static void nfs_process_read(void *arg)
{
NFSClient *client = arg;
- aio_context_acquire(client->aio_context);
+ qemu_mutex_lock(&client->mutex);
nfs_service(client->context, POLLIN);
nfs_set_events(client);
- aio_context_release(client->aio_context);
+ qemu_mutex_unlock(&client->mutex);
}
static void nfs_process_write(void *arg)
{
NFSClient *client = arg;
- aio_context_acquire(client->aio_context);
+ qemu_mutex_lock(&client->mutex);
nfs_service(client->context, POLLOUT);
nfs_set_events(client);
- aio_context_release(client->aio_context);
+ qemu_mutex_unlock(&client->mutex);
}
static void nfs_co_init_task(BlockDriverState *bs, NFSRPC *task)
@@ -242,6 +244,7 @@ static void nfs_co_generic_bh_cb(void *opaque)
aio_co_wake(task->co);
}
+/* Called (via nfs_service) with QemuMutex held. */
static void
nfs_co_generic_cb(int ret, struct nfs_context *nfs, void *data,
void *private_data)
@@ -273,14 +276,17 @@ static int coroutine_fn nfs_co_readv(BlockDriverState *bs,
nfs_co_init_task(bs, &task);
task.iov = iov;
+ qemu_mutex_lock(&client->mutex);
if (nfs_pread_async(client->context, client->fh,
sector_num * BDRV_SECTOR_SIZE,
nb_sectors * BDRV_SECTOR_SIZE,
nfs_co_generic_cb, &task) != 0) {
+ qemu_mutex_unlock(&client->mutex);
return -ENOMEM;
}
nfs_set_events(client);
+ qemu_mutex_unlock(&client->mutex);
while (!task.complete) {
qemu_coroutine_yield();
}
@@ -314,15 +320,18 @@ static int coroutine_fn nfs_co_writev(BlockDriverState
*bs,
qemu_iovec_to_buf(iov, 0, buf, nb_sectors * BDRV_SECTOR_SIZE);
+ qemu_mutex_lock(&client->mutex);
if (nfs_pwrite_async(client->context, client->fh,
sector_num * BDRV_SECTOR_SIZE,
nb_sectors * BDRV_SECTOR_SIZE,
buf, nfs_co_generic_cb, &task) != 0) {
+ qemu_mutex_unlock(&client->mutex);
g_free(buf);
return -ENOMEM;
}
nfs_set_events(client);
+ qemu_mutex_unlock(&client->mutex);
while (!task.complete) {
qemu_coroutine_yield();
}
@@ -343,12 +352,15 @@ static int coroutine_fn nfs_co_flush(BlockDriverState *bs)
nfs_co_init_task(bs, &task);
+ qemu_mutex_lock(&client->mutex);
if (nfs_fsync_async(client->context, client->fh, nfs_co_generic_cb,
&task) != 0) {
+ qemu_mutex_unlock(&client->mutex);
return -ENOMEM;
}
nfs_set_events(client);
+ qemu_mutex_unlock(&client->mutex);
while (!task.complete) {
qemu_coroutine_yield();
}
@@ -434,6 +446,7 @@ static void nfs_file_close(BlockDriverState *bs)
{
NFSClient *client = bs->opaque;
nfs_client_close(client);
+ qemu_mutex_destroy(&client->mutex);
}
static NFSServer *nfs_config(QDict *options, Error **errp)
@@ -641,6 +654,7 @@ static int nfs_file_open(BlockDriverState *bs, QDict
*options, int flags,
if (ret < 0) {
return ret;
}
+ qemu_mutex_init(&client->mutex);
bs->total_sectors = ret;
ret = 0;
return ret;
@@ -696,6 +710,7 @@ static int nfs_has_zero_init(BlockDriverState *bs)
return client->has_zero_init;
}
+/* Called (via nfs_service) with QemuMutex held. */
static void
nfs_get_allocated_file_size_cb(int ret, struct nfs_context *nfs, void *data,
void *private_data)
--
2.9.3
