diff options
| -rw-r--r-- | block/qed-cluster.c | 4 | ||||
| -rw-r--r-- | block/qed-l2-cache.c | 6 | ||||
| -rw-r--r-- | block/qed-table.c | 24 | ||||
| -rw-r--r-- | block/qed.c | 138 | ||||
| -rw-r--r-- | block/qed.h | 11 |
5 files changed, 129 insertions, 54 deletions
diff --git a/block/qed-cluster.c b/block/qed-cluster.c index d8d6e66a0f..672e2e654b 100644 --- a/block/qed-cluster.c +++ b/block/qed-cluster.c @@ -85,6 +85,8 @@ static unsigned int qed_count_contiguous_clusters(BDRVQEDState *s, * * On failure QED_CLUSTER_L2 or QED_CLUSTER_L1 is returned for missing L2 or L1 * table offset, respectively. len is number of contiguous unallocated bytes. + * + * Called with table_lock held. */ int coroutine_fn qed_find_cluster(BDRVQEDState *s, QEDRequest *request, uint64_t pos, size_t *len, @@ -112,7 +114,6 @@ int coroutine_fn qed_find_cluster(BDRVQEDState *s, QEDRequest *request, } ret = qed_read_l2_table(s, request, l2_offset); - qed_acquire(s); if (ret) { goto out; } @@ -137,6 +138,5 @@ int coroutine_fn qed_find_cluster(BDRVQEDState *s, QEDRequest *request, out: *img_offset = offset; - qed_release(s); return ret; } diff --git a/block/qed-l2-cache.c b/block/qed-l2-cache.c index 5cba794650..b548362398 100644 --- a/block/qed-l2-cache.c +++ b/block/qed-l2-cache.c @@ -101,6 +101,8 @@ CachedL2Table *qed_alloc_l2_cache_entry(L2TableCache *l2_cache) /** * Decrease an entry's reference count and free if necessary when the reference * count drops to zero. + * + * Called with table_lock held. */ void qed_unref_l2_cache_entry(CachedL2Table *entry) { @@ -122,6 +124,8 @@ void qed_unref_l2_cache_entry(CachedL2Table *entry) * * For a cached entry, this function increases the reference count and returns * the entry. + * + * Called with table_lock held. */ CachedL2Table *qed_find_l2_cache_entry(L2TableCache *l2_cache, uint64_t offset) { @@ -150,6 +154,8 @@ CachedL2Table *qed_find_l2_cache_entry(L2TableCache *l2_cache, uint64_t offset) * N.B. This function steals a reference to the l2_table from the caller so the * caller must obtain a new reference by issuing a call to * qed_find_l2_cache_entry(). + * + * Called with table_lock held. */ void qed_commit_l2_cache_entry(L2TableCache *l2_cache, CachedL2Table *l2_table) { diff --git a/block/qed-table.c b/block/qed-table.c index ebee2c50f0..eead8b0fc7 100644 --- a/block/qed-table.c +++ b/block/qed-table.c @@ -18,6 +18,7 @@ #include "qed.h" #include "qemu/bswap.h" +/* Called either from qed_check or with table_lock held. */ static int qed_read_table(BDRVQEDState *s, uint64_t offset, QEDTable *table) { QEMUIOVector qiov; @@ -32,18 +33,22 @@ static int qed_read_table(BDRVQEDState *s, uint64_t offset, QEDTable *table) trace_qed_read_table(s, offset, table); + if (qemu_in_coroutine()) { + qemu_co_mutex_unlock(&s->table_lock); + } ret = bdrv_preadv(s->bs->file, offset, &qiov); + if (qemu_in_coroutine()) { + qemu_co_mutex_lock(&s->table_lock); + } if (ret < 0) { goto out; } /* Byteswap offsets */ - qed_acquire(s); noffsets = qiov.size / sizeof(uint64_t); for (i = 0; i < noffsets; i++) { table->offsets[i] = le64_to_cpu(table->offsets[i]); } - qed_release(s); ret = 0; out: @@ -61,6 +66,8 @@ out: * @index: Index of first element * @n: Number of elements * @flush: Whether or not to sync to disk + * + * Called either from qed_check or with table_lock held. */ static int qed_write_table(BDRVQEDState *s, uint64_t offset, QEDTable *table, unsigned int index, unsigned int n, bool flush) @@ -97,16 +104,20 @@ static int qed_write_table(BDRVQEDState *s, uint64_t offset, QEDTable *table, /* Adjust for offset into table */ offset += start * sizeof(uint64_t); + if (qemu_in_coroutine()) { + qemu_co_mutex_unlock(&s->table_lock); + } ret = bdrv_pwritev(s->bs->file, offset, &qiov); + if (qemu_in_coroutine()) { + qemu_co_mutex_lock(&s->table_lock); + } trace_qed_write_table_cb(s, table, flush, ret); if (ret < 0) { goto out; } if (flush) { - qed_acquire(s); ret = bdrv_flush(s->bs); - qed_release(s); if (ret < 0) { goto out; } @@ -123,6 +134,7 @@ int qed_read_l1_table_sync(BDRVQEDState *s) return qed_read_table(s, s->header.l1_table_offset, s->l1_table); } +/* Called either from qed_check or with table_lock held. */ int qed_write_l1_table(BDRVQEDState *s, unsigned int index, unsigned int n) { BLKDBG_EVENT(s->bs->file, BLKDBG_L1_UPDATE); @@ -136,6 +148,7 @@ int qed_write_l1_table_sync(BDRVQEDState *s, unsigned int index, return qed_write_l1_table(s, index, n); } +/* Called either from qed_check or with table_lock held. */ int qed_read_l2_table(BDRVQEDState *s, QEDRequest *request, uint64_t offset) { int ret; @@ -154,7 +167,6 @@ int qed_read_l2_table(BDRVQEDState *s, QEDRequest *request, uint64_t offset) BLKDBG_EVENT(s->bs->file, BLKDBG_L2_LOAD); ret = qed_read_table(s, offset, request->l2_table->table); - qed_acquire(s); if (ret) { /* can't trust loaded L2 table anymore */ qed_unref_l2_cache_entry(request->l2_table); @@ -170,7 +182,6 @@ int qed_read_l2_table(BDRVQEDState *s, QEDRequest *request, uint64_t offset) request->l2_table = qed_find_l2_cache_entry(&s->l2_cache, offset); assert(request->l2_table != NULL); } - qed_release(s); return ret; } @@ -180,6 +191,7 @@ int qed_read_l2_table_sync(BDRVQEDState *s, QEDRequest *request, uint64_t offset return qed_read_l2_table(s, request, offset); } +/* Called either from qed_check or with table_lock held. */ int qed_write_l2_table(BDRVQEDState *s, QEDRequest *request, unsigned int index, unsigned int n, bool flush) { diff --git a/block/qed.c b/block/qed.c index adcc5c967f..dc54bf4a93 100644 --- a/block/qed.c +++ b/block/qed.c @@ -93,6 +93,8 @@ int qed_write_header_sync(BDRVQEDState *s) * * This function only updates known header fields in-place and does not affect * extra data after the QED header. + * + * No new allocating reqs can start while this function runs. */ static int coroutine_fn qed_write_header(BDRVQEDState *s) { @@ -109,6 +111,8 @@ static int coroutine_fn qed_write_header(BDRVQEDState *s) QEMUIOVector qiov; int ret; + assert(s->allocating_acb || s->allocating_write_reqs_plugged); + buf = qemu_blockalign(s->bs, len); iov = (struct iovec) { .iov_base = buf, @@ -219,6 +223,8 @@ static int qed_read_string(BdrvChild *file, uint64_t offset, size_t n, * This function only produces the offset where the new clusters should be * written. It updates BDRVQEDState but does not make any changes to the image * file. + * + * Called with table_lock held. */ static uint64_t qed_alloc_clusters(BDRVQEDState *s, unsigned int n) { @@ -236,6 +242,8 @@ QEDTable *qed_alloc_table(BDRVQEDState *s) /** * Allocate a new zeroed L2 table + * + * Called with table_lock held. */ static CachedL2Table *qed_new_l2_table(BDRVQEDState *s) { @@ -249,19 +257,32 @@ static CachedL2Table *qed_new_l2_table(BDRVQEDState *s) return l2_table; } -static void qed_plug_allocating_write_reqs(BDRVQEDState *s) +static bool qed_plug_allocating_write_reqs(BDRVQEDState *s) { + qemu_co_mutex_lock(&s->table_lock); + + /* No reentrancy is allowed. */ assert(!s->allocating_write_reqs_plugged); + if (s->allocating_acb != NULL) { + /* Another allocating write came concurrently. This cannot happen + * from bdrv_qed_co_drain, but it can happen when the timer runs. + */ + qemu_co_mutex_unlock(&s->table_lock); + return false; + } s->allocating_write_reqs_plugged = true; + qemu_co_mutex_unlock(&s->table_lock); + return true; } static void qed_unplug_allocating_write_reqs(BDRVQEDState *s) { + qemu_co_mutex_lock(&s->table_lock); assert(s->allocating_write_reqs_plugged); - s->allocating_write_reqs_plugged = false; - qemu_co_enter_next(&s->allocating_write_reqs); + qemu_co_queue_next(&s->allocating_write_reqs); + qemu_co_mutex_unlock(&s->table_lock); } static void coroutine_fn qed_need_check_timer_entry(void *opaque) @@ -269,17 +290,14 @@ static void coroutine_fn qed_need_check_timer_entry(void *opaque) BDRVQEDState *s = opaque; int ret; - /* The timer should only fire when allocating writes have drained */ - assert(!s->allocating_acb); - trace_qed_need_check_timer_cb(s); - qed_acquire(s); - qed_plug_allocating_write_reqs(s); + if (!qed_plug_allocating_write_reqs(s)) { + return; + } /* Ensure writes are on disk before clearing flag */ ret = bdrv_co_flush(s->bs->file->bs); - qed_release(s); if (ret < 0) { qed_unplug_allocating_write_reqs(s); return; @@ -301,16 +319,6 @@ static void qed_need_check_timer_cb(void *opaque) qemu_coroutine_enter(co); } -void qed_acquire(BDRVQEDState *s) -{ - aio_context_acquire(bdrv_get_aio_context(s->bs)); -} - -void qed_release(BDRVQEDState *s) -{ - aio_context_release(bdrv_get_aio_context(s->bs)); -} - static void qed_start_need_check_timer(BDRVQEDState *s) { trace_qed_start_need_check_timer(s); @@ -369,6 +377,7 @@ static void bdrv_qed_init_state(BlockDriverState *bs) memset(s, 0, sizeof(BDRVQEDState)); s->bs = bs; + qemu_co_mutex_init(&s->table_lock); qemu_co_queue_init(&s->allocating_write_reqs); } @@ -688,6 +697,7 @@ typedef struct { BlockDriverState **file; } QEDIsAllocatedCB; +/* Called with table_lock held. */ static void qed_is_allocated_cb(void *opaque, int ret, uint64_t offset, size_t len) { QEDIsAllocatedCB *cb = opaque; @@ -735,6 +745,7 @@ static int64_t coroutine_fn bdrv_qed_co_get_block_status(BlockDriverState *bs, uint64_t offset; int ret; + qemu_co_mutex_lock(&s->table_lock); ret = qed_find_cluster(s, &request, cb.pos, &len, &offset); qed_is_allocated_cb(&cb, ret, offset, len); @@ -742,6 +753,7 @@ static int64_t coroutine_fn bdrv_qed_co_get_block_status(BlockDriverState *bs, assert(cb.status != BDRV_BLOCK_OFFSET_MASK); qed_unref_l2_cache_entry(request.l2_table); + qemu_co_mutex_unlock(&s->table_lock); return cb.status; } @@ -872,6 +884,8 @@ out: * * The cluster offset may be an allocated byte offset in the image file, the * zero cluster marker, or the unallocated cluster marker. + * + * Called with table_lock held. */ static void coroutine_fn qed_update_l2_table(BDRVQEDState *s, QEDTable *table, int index, unsigned int n, @@ -887,6 +901,7 @@ static void coroutine_fn qed_update_l2_table(BDRVQEDState *s, QEDTable *table, } } +/* Called with table_lock held. */ static void coroutine_fn qed_aio_complete(QEDAIOCB *acb) { BDRVQEDState *s = acb_to_s(acb); @@ -910,7 +925,7 @@ static void coroutine_fn qed_aio_complete(QEDAIOCB *acb) if (acb == s->allocating_acb) { s->allocating_acb = NULL; if (!qemu_co_queue_empty(&s->allocating_write_reqs)) { - qemu_co_enter_next(&s->allocating_write_reqs); + qemu_co_queue_next(&s->allocating_write_reqs); } else if (s->header.features & QED_F_NEED_CHECK) { qed_start_need_check_timer(s); } @@ -919,6 +934,8 @@ static void coroutine_fn qed_aio_complete(QEDAIOCB *acb) /** * Update L1 table with new L2 table offset and write it out + * + * Called with table_lock held. */ static int coroutine_fn qed_aio_write_l1_update(QEDAIOCB *acb) { @@ -947,6 +964,8 @@ static int coroutine_fn qed_aio_write_l1_update(QEDAIOCB *acb) /** * Update L2 table with new cluster offsets and write them out + * + * Called with table_lock held. */ static int coroutine_fn qed_aio_write_l2_update(QEDAIOCB *acb, uint64_t offset) { @@ -983,6 +1002,8 @@ static int coroutine_fn qed_aio_write_l2_update(QEDAIOCB *acb, uint64_t offset) /** * Write data to the image file + * + * Called with table_lock *not* held. */ static int coroutine_fn qed_aio_write_main(QEDAIOCB *acb) { @@ -999,6 +1020,8 @@ static int coroutine_fn qed_aio_write_main(QEDAIOCB *acb) /** * Populate untouched regions of new data cluster + * + * Called with table_lock held. */ static int coroutine_fn qed_aio_write_cow(QEDAIOCB *acb) { @@ -1006,6 +1029,8 @@ static int coroutine_fn qed_aio_write_cow(QEDAIOCB *acb) uint64_t start, len, offset; int ret; + qemu_co_mutex_unlock(&s->table_lock); + /* Populate front untouched region of new data cluster */ start = qed_start_of_cluster(s, acb->cur_pos); len = qed_offset_into_cluster(s, acb->cur_pos); @@ -1013,7 +1038,7 @@ static int coroutine_fn qed_aio_write_cow(QEDAIOCB *acb) trace_qed_aio_write_prefill(s, acb, start, len, acb->cur_cluster); ret = qed_copy_from_backing_file(s, start, len, acb->cur_cluster); if (ret < 0) { - return ret; + goto out; } /* Populate back untouched region of new data cluster */ @@ -1026,12 +1051,12 @@ static int coroutine_fn qed_aio_write_cow(QEDAIOCB *acb) trace_qed_aio_write_postfill(s, acb, start, len, offset); ret = qed_copy_from_backing_file(s, start, len, offset); if (ret < 0) { - return ret; + goto out; } ret = qed_aio_write_main(acb); if (ret < 0) { - return ret; + goto out; } if (s->bs->backing) { @@ -1046,12 +1071,11 @@ static int coroutine_fn qed_aio_write_cow(QEDAIOCB *acb) * cluster and before updating the L2 table. */ ret = bdrv_co_flush(s->bs->file->bs); - if (ret < 0) { - return ret; - } } - return 0; +out: + qemu_co_mutex_lock(&s->table_lock); + return ret; } /** @@ -1074,6 +1098,8 @@ static bool qed_should_set_need_check(BDRVQEDState *s) * @len: Length in bytes * * This path is taken when writing to previously unallocated clusters. + * + * Called with table_lock held. */ static int coroutine_fn qed_aio_write_alloc(QEDAIOCB *acb, size_t len) { @@ -1088,7 +1114,7 @@ static int coroutine_fn qed_aio_write_alloc(QEDAIOCB *acb, size_t len) /* Freeze this request if another allocating write is in progress */ if (s->allocating_acb != acb || s->allocating_write_reqs_plugged) { if (s->allocating_acb != NULL) { - qemu_co_queue_wait(&s->allocating_write_reqs, NULL); + qemu_co_queue_wait(&s->allocating_write_reqs, &s->table_lock); assert(s->allocating_acb == NULL); } s->allocating_acb = acb; @@ -1135,10 +1161,17 @@ static int coroutine_fn qed_aio_write_alloc(QEDAIOCB *acb, size_t len) * @len: Length in bytes * * This path is taken when writing to already allocated clusters. + * + * Called with table_lock held. */ static int coroutine_fn qed_aio_write_inplace(QEDAIOCB *acb, uint64_t offset, size_t len) { + BDRVQEDState *s = acb_to_s(acb); + int r; + + qemu_co_mutex_unlock(&s->table_lock); + /* Allocate buffer for zero writes */ if (acb->flags & QED_AIOCB_ZERO) { struct iovec *iov = acb->qiov->iov; @@ -1146,7 +1179,8 @@ static int coroutine_fn qed_aio_write_inplace(QEDAIOCB *acb, uint64_t offset, if (!iov->iov_base) { iov->iov_base = qemu_try_blockalign(acb->bs, iov->iov_len); if (iov->iov_base == NULL) { - return -ENOMEM; + r = -ENOMEM; + goto out; } memset(iov->iov_base, 0, iov->iov_len); } @@ -1156,8 +1190,11 @@ static int coroutine_fn qed_aio_write_inplace(QEDAIOCB *acb, uint64_t offset, acb->cur_cluster = offset; qemu_iovec_concat(&acb->cur_qiov, acb->qiov, acb->qiov_offset, len); - /* Do the actual write */ - return qed_aio_write_main(acb); + /* Do the actual write. */ + r = qed_aio_write_main(acb); +out: + qemu_co_mutex_lock(&s->table_lock); + return r; } /** @@ -1167,6 +1204,8 @@ static int coroutine_fn qed_aio_write_inplace(QEDAIOCB *acb, uint64_t offset, * @ret: QED_CLUSTER_FOUND, QED_CLUSTER_L2 or QED_CLUSTER_L1 * @offset: Cluster offset in bytes * @len: Length in bytes + * + * Called with table_lock held. */ static int coroutine_fn qed_aio_write_data(void *opaque, int ret, uint64_t offset, size_t len) @@ -1198,6 +1237,8 @@ static int coroutine_fn qed_aio_write_data(void *opaque, int ret, * @ret: QED_CLUSTER_FOUND, QED_CLUSTER_L2 or QED_CLUSTER_L1 * @offset: Cluster offset in bytes * @len: Length in bytes + * + * Called with table_lock held. */ static int coroutine_fn qed_aio_read_data(void *opaque, int ret, uint64_t offset, size_t len) @@ -1205,6 +1246,9 @@ static int coroutine_fn qed_aio_read_data(void *opaque, int ret, QEDAIOCB *acb = opaque; BDRVQEDState *s = acb_to_s(acb); BlockDriverState *bs = acb->bs; + int r; + + qemu_co_mutex_unlock(&s->table_lock); /* Adjust offset into cluster */ offset += qed_offset_into_cluster(s, acb->cur_pos); @@ -1213,22 +1257,23 @@ static int coroutine_fn qed_aio_read_data(void *opaque, int ret, qemu_iovec_concat(&acb->cur_qiov, acb->qiov, acb->qiov_offset, len); - /* Handle zero cluster and backing file reads */ + /* Handle zero cluster and backing file reads, otherwise read + * data cluster directly. + */ if (ret == QED_CLUSTER_ZERO) { qemu_iovec_memset(&acb->cur_qiov, 0, 0, acb->cur_qiov.size); - return 0; + r = 0; } else if (ret != QED_CLUSTER_FOUND) { - return qed_read_backing_file(s, acb->cur_pos, &acb->cur_qiov, - &acb->backing_qiov); + r = qed_read_backing_file(s, acb->cur_pos, &acb->cur_qiov, + &acb->backing_qiov); + } else { + BLKDBG_EVENT(bs->file, BLKDBG_READ_AIO); + r = bdrv_co_preadv(bs->file, offset, acb->cur_qiov.size, + &acb->cur_qiov, 0); } - BLKDBG_EVENT(bs->file, BLKDBG_READ_AIO); - ret = bdrv_co_preadv(bs->file, offset, acb->cur_qiov.size, - &acb->cur_qiov, 0); - if (ret < 0) { - return ret; - } - return 0; + qemu_co_mutex_lock(&s->table_lock); + return r; } /** @@ -1241,6 +1286,7 @@ static int coroutine_fn qed_aio_next_io(QEDAIOCB *acb) size_t len; int ret; + qemu_co_mutex_lock(&s->table_lock); while (1) { trace_qed_aio_next_io(s, acb, 0, acb->cur_pos + acb->cur_qiov.size); @@ -1280,6 +1326,7 @@ static int coroutine_fn qed_aio_next_io(QEDAIOCB *acb) trace_qed_aio_complete(s, acb, ret); qed_aio_complete(acb); + qemu_co_mutex_unlock(&s->table_lock); return ret; } @@ -1469,13 +1516,20 @@ static int bdrv_qed_change_backing_file(BlockDriverState *bs, static void bdrv_qed_invalidate_cache(BlockDriverState *bs, Error **errp) { + BDRVQEDState *s = bs->opaque; Error *local_err = NULL; int ret; bdrv_qed_close(bs); bdrv_qed_init_state(bs); + if (qemu_in_coroutine()) { + qemu_co_mutex_lock(&s->table_lock); + } ret = bdrv_qed_do_open(bs, NULL, bs->open_flags, &local_err); + if (qemu_in_coroutine()) { + qemu_co_mutex_unlock(&s->table_lock); + } if (local_err) { error_propagate(errp, local_err); error_prepend(errp, "Could not reopen qed layer: "); diff --git a/block/qed.h b/block/qed.h index dd3a2d5519..f35341f134 100644 --- a/block/qed.h +++ b/block/qed.h @@ -151,15 +151,21 @@ typedef struct QEDAIOCB { typedef struct { BlockDriverState *bs; /* device */ - uint64_t file_size; /* length of image file, in bytes */ + /* Written only by an allocating write or the timer handler (the latter + * while allocating reqs are plugged). + */ QEDHeader header; /* always cpu-endian */ + + /* Protected by table_lock. */ + CoMutex table_lock; QEDTable *l1_table; L2TableCache l2_cache; /* l2 table cache */ uint32_t table_nelems; uint32_t l1_shift; uint32_t l2_shift; uint32_t l2_mask; + uint64_t file_size; /* length of image file, in bytes */ /* Allocating write request queue */ QEDAIOCB *allocating_acb; @@ -177,9 +183,6 @@ enum { QED_CLUSTER_L1, /* cluster missing in L1 */ }; -void qed_acquire(BDRVQEDState *s); -void qed_release(BDRVQEDState *s); - /** * Header functions */ |