diff options
Diffstat (limited to 'qemu/block/qed.c')
| -rw-r--r-- | qemu/block/qed.c | 1689 |
1 files changed, 0 insertions, 1689 deletions
diff --git a/qemu/block/qed.c b/qemu/block/qed.c deleted file mode 100644 index 0af52741d..000000000 --- a/qemu/block/qed.c +++ /dev/null @@ -1,1689 +0,0 @@ -/* - * QEMU Enhanced Disk Format - * - * Copyright IBM, Corp. 2010 - * - * Authors: - * Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> - * Anthony Liguori <aliguori@us.ibm.com> - * - * This work is licensed under the terms of the GNU LGPL, version 2 or later. - * See the COPYING.LIB file in the top-level directory. - * - */ - -#include "qemu/osdep.h" -#include "qapi/error.h" -#include "qemu/timer.h" -#include "trace.h" -#include "qed.h" -#include "qapi/qmp/qerror.h" -#include "migration/migration.h" -#include "sysemu/block-backend.h" - -static const AIOCBInfo qed_aiocb_info = { - .aiocb_size = sizeof(QEDAIOCB), -}; - -static int bdrv_qed_probe(const uint8_t *buf, int buf_size, - const char *filename) -{ - const QEDHeader *header = (const QEDHeader *)buf; - - if (buf_size < sizeof(*header)) { - return 0; - } - if (le32_to_cpu(header->magic) != QED_MAGIC) { - return 0; - } - return 100; -} - -/** - * Check whether an image format is raw - * - * @fmt: Backing file format, may be NULL - */ -static bool qed_fmt_is_raw(const char *fmt) -{ - return fmt && strcmp(fmt, "raw") == 0; -} - -static void qed_header_le_to_cpu(const QEDHeader *le, QEDHeader *cpu) -{ - cpu->magic = le32_to_cpu(le->magic); - cpu->cluster_size = le32_to_cpu(le->cluster_size); - cpu->table_size = le32_to_cpu(le->table_size); - cpu->header_size = le32_to_cpu(le->header_size); - cpu->features = le64_to_cpu(le->features); - cpu->compat_features = le64_to_cpu(le->compat_features); - cpu->autoclear_features = le64_to_cpu(le->autoclear_features); - cpu->l1_table_offset = le64_to_cpu(le->l1_table_offset); - cpu->image_size = le64_to_cpu(le->image_size); - cpu->backing_filename_offset = le32_to_cpu(le->backing_filename_offset); - cpu->backing_filename_size = le32_to_cpu(le->backing_filename_size); -} - -static void qed_header_cpu_to_le(const QEDHeader *cpu, QEDHeader *le) -{ - le->magic = cpu_to_le32(cpu->magic); - le->cluster_size = cpu_to_le32(cpu->cluster_size); - le->table_size = cpu_to_le32(cpu->table_size); - le->header_size = cpu_to_le32(cpu->header_size); - le->features = cpu_to_le64(cpu->features); - le->compat_features = cpu_to_le64(cpu->compat_features); - le->autoclear_features = cpu_to_le64(cpu->autoclear_features); - le->l1_table_offset = cpu_to_le64(cpu->l1_table_offset); - le->image_size = cpu_to_le64(cpu->image_size); - le->backing_filename_offset = cpu_to_le32(cpu->backing_filename_offset); - le->backing_filename_size = cpu_to_le32(cpu->backing_filename_size); -} - -int qed_write_header_sync(BDRVQEDState *s) -{ - QEDHeader le; - int ret; - - qed_header_cpu_to_le(&s->header, &le); - ret = bdrv_pwrite(s->bs->file->bs, 0, &le, sizeof(le)); - if (ret != sizeof(le)) { - return ret; - } - return 0; -} - -typedef struct { - GenericCB gencb; - BDRVQEDState *s; - struct iovec iov; - QEMUIOVector qiov; - int nsectors; - uint8_t *buf; -} QEDWriteHeaderCB; - -static void qed_write_header_cb(void *opaque, int ret) -{ - QEDWriteHeaderCB *write_header_cb = opaque; - - qemu_vfree(write_header_cb->buf); - gencb_complete(write_header_cb, ret); -} - -static void qed_write_header_read_cb(void *opaque, int ret) -{ - QEDWriteHeaderCB *write_header_cb = opaque; - BDRVQEDState *s = write_header_cb->s; - - if (ret) { - qed_write_header_cb(write_header_cb, ret); - return; - } - - /* Update header */ - qed_header_cpu_to_le(&s->header, (QEDHeader *)write_header_cb->buf); - - bdrv_aio_writev(s->bs->file->bs, 0, &write_header_cb->qiov, - write_header_cb->nsectors, qed_write_header_cb, - write_header_cb); -} - -/** - * Update header in-place (does not rewrite backing filename or other strings) - * - * This function only updates known header fields in-place and does not affect - * extra data after the QED header. - */ -static void qed_write_header(BDRVQEDState *s, BlockCompletionFunc cb, - void *opaque) -{ - /* We must write full sectors for O_DIRECT but cannot necessarily generate - * the data following the header if an unrecognized compat feature is - * active. Therefore, first read the sectors containing the header, update - * them, and write back. - */ - - int nsectors = (sizeof(QEDHeader) + BDRV_SECTOR_SIZE - 1) / - BDRV_SECTOR_SIZE; - size_t len = nsectors * BDRV_SECTOR_SIZE; - QEDWriteHeaderCB *write_header_cb = gencb_alloc(sizeof(*write_header_cb), - cb, opaque); - - write_header_cb->s = s; - write_header_cb->nsectors = nsectors; - write_header_cb->buf = qemu_blockalign(s->bs, len); - write_header_cb->iov.iov_base = write_header_cb->buf; - write_header_cb->iov.iov_len = len; - qemu_iovec_init_external(&write_header_cb->qiov, &write_header_cb->iov, 1); - - bdrv_aio_readv(s->bs->file->bs, 0, &write_header_cb->qiov, nsectors, - qed_write_header_read_cb, write_header_cb); -} - -static uint64_t qed_max_image_size(uint32_t cluster_size, uint32_t table_size) -{ - uint64_t table_entries; - uint64_t l2_size; - - table_entries = (table_size * cluster_size) / sizeof(uint64_t); - l2_size = table_entries * cluster_size; - - return l2_size * table_entries; -} - -static bool qed_is_cluster_size_valid(uint32_t cluster_size) -{ - if (cluster_size < QED_MIN_CLUSTER_SIZE || - cluster_size > QED_MAX_CLUSTER_SIZE) { - return false; - } - if (cluster_size & (cluster_size - 1)) { - return false; /* not power of 2 */ - } - return true; -} - -static bool qed_is_table_size_valid(uint32_t table_size) -{ - if (table_size < QED_MIN_TABLE_SIZE || - table_size > QED_MAX_TABLE_SIZE) { - return false; - } - if (table_size & (table_size - 1)) { - return false; /* not power of 2 */ - } - return true; -} - -static bool qed_is_image_size_valid(uint64_t image_size, uint32_t cluster_size, - uint32_t table_size) -{ - if (image_size % BDRV_SECTOR_SIZE != 0) { - return false; /* not multiple of sector size */ - } - if (image_size > qed_max_image_size(cluster_size, table_size)) { - return false; /* image is too large */ - } - return true; -} - -/** - * Read a string of known length from the image file - * - * @file: Image file - * @offset: File offset to start of string, in bytes - * @n: String length in bytes - * @buf: Destination buffer - * @buflen: Destination buffer length in bytes - * @ret: 0 on success, -errno on failure - * - * The string is NUL-terminated. - */ -static int qed_read_string(BlockDriverState *file, uint64_t offset, size_t n, - char *buf, size_t buflen) -{ - int ret; - if (n >= buflen) { - return -EINVAL; - } - ret = bdrv_pread(file, offset, buf, n); - if (ret < 0) { - return ret; - } - buf[n] = '\0'; - return 0; -} - -/** - * Allocate new clusters - * - * @s: QED state - * @n: Number of contiguous clusters to allocate - * @ret: Offset of first allocated cluster - * - * 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. - */ -static uint64_t qed_alloc_clusters(BDRVQEDState *s, unsigned int n) -{ - uint64_t offset = s->file_size; - s->file_size += n * s->header.cluster_size; - return offset; -} - -QEDTable *qed_alloc_table(BDRVQEDState *s) -{ - /* Honor O_DIRECT memory alignment requirements */ - return qemu_blockalign(s->bs, - s->header.cluster_size * s->header.table_size); -} - -/** - * Allocate a new zeroed L2 table - */ -static CachedL2Table *qed_new_l2_table(BDRVQEDState *s) -{ - CachedL2Table *l2_table = qed_alloc_l2_cache_entry(&s->l2_cache); - - l2_table->table = qed_alloc_table(s); - l2_table->offset = qed_alloc_clusters(s, s->header.table_size); - - memset(l2_table->table->offsets, 0, - s->header.cluster_size * s->header.table_size); - return l2_table; -} - -static void qed_aio_next_io(void *opaque, int ret); - -static void qed_plug_allocating_write_reqs(BDRVQEDState *s) -{ - assert(!s->allocating_write_reqs_plugged); - - s->allocating_write_reqs_plugged = true; -} - -static void qed_unplug_allocating_write_reqs(BDRVQEDState *s) -{ - QEDAIOCB *acb; - - assert(s->allocating_write_reqs_plugged); - - s->allocating_write_reqs_plugged = false; - - acb = QSIMPLEQ_FIRST(&s->allocating_write_reqs); - if (acb) { - qed_aio_next_io(acb, 0); - } -} - -static void qed_finish_clear_need_check(void *opaque, int ret) -{ - /* Do nothing */ -} - -static void qed_flush_after_clear_need_check(void *opaque, int ret) -{ - BDRVQEDState *s = opaque; - - bdrv_aio_flush(s->bs, qed_finish_clear_need_check, s); - - /* No need to wait until flush completes */ - qed_unplug_allocating_write_reqs(s); -} - -static void qed_clear_need_check(void *opaque, int ret) -{ - BDRVQEDState *s = opaque; - - if (ret) { - qed_unplug_allocating_write_reqs(s); - return; - } - - s->header.features &= ~QED_F_NEED_CHECK; - qed_write_header(s, qed_flush_after_clear_need_check, s); -} - -static void qed_need_check_timer_cb(void *opaque) -{ - BDRVQEDState *s = opaque; - - /* The timer should only fire when allocating writes have drained */ - assert(!QSIMPLEQ_FIRST(&s->allocating_write_reqs)); - - trace_qed_need_check_timer_cb(s); - - qed_plug_allocating_write_reqs(s); - - /* Ensure writes are on disk before clearing flag */ - bdrv_aio_flush(s->bs, qed_clear_need_check, s); -} - -static void qed_start_need_check_timer(BDRVQEDState *s) -{ - trace_qed_start_need_check_timer(s); - - /* Use QEMU_CLOCK_VIRTUAL so we don't alter the image file while suspended for - * migration. - */ - timer_mod(s->need_check_timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + - NANOSECONDS_PER_SECOND * QED_NEED_CHECK_TIMEOUT); -} - -/* It's okay to call this multiple times or when no timer is started */ -static void qed_cancel_need_check_timer(BDRVQEDState *s) -{ - trace_qed_cancel_need_check_timer(s); - timer_del(s->need_check_timer); -} - -static void bdrv_qed_detach_aio_context(BlockDriverState *bs) -{ - BDRVQEDState *s = bs->opaque; - - qed_cancel_need_check_timer(s); - timer_free(s->need_check_timer); -} - -static void bdrv_qed_attach_aio_context(BlockDriverState *bs, - AioContext *new_context) -{ - BDRVQEDState *s = bs->opaque; - - s->need_check_timer = aio_timer_new(new_context, - QEMU_CLOCK_VIRTUAL, SCALE_NS, - qed_need_check_timer_cb, s); - if (s->header.features & QED_F_NEED_CHECK) { - qed_start_need_check_timer(s); - } -} - -static int bdrv_qed_open(BlockDriverState *bs, QDict *options, int flags, - Error **errp) -{ - BDRVQEDState *s = bs->opaque; - QEDHeader le_header; - int64_t file_size; - int ret; - - s->bs = bs; - QSIMPLEQ_INIT(&s->allocating_write_reqs); - - ret = bdrv_pread(bs->file->bs, 0, &le_header, sizeof(le_header)); - if (ret < 0) { - return ret; - } - qed_header_le_to_cpu(&le_header, &s->header); - - if (s->header.magic != QED_MAGIC) { - error_setg(errp, "Image not in QED format"); - return -EINVAL; - } - if (s->header.features & ~QED_FEATURE_MASK) { - /* image uses unsupported feature bits */ - error_setg(errp, "Unsupported QED features: %" PRIx64, - s->header.features & ~QED_FEATURE_MASK); - return -ENOTSUP; - } - if (!qed_is_cluster_size_valid(s->header.cluster_size)) { - return -EINVAL; - } - - /* Round down file size to the last cluster */ - file_size = bdrv_getlength(bs->file->bs); - if (file_size < 0) { - return file_size; - } - s->file_size = qed_start_of_cluster(s, file_size); - - if (!qed_is_table_size_valid(s->header.table_size)) { - return -EINVAL; - } - if (!qed_is_image_size_valid(s->header.image_size, - s->header.cluster_size, - s->header.table_size)) { - return -EINVAL; - } - if (!qed_check_table_offset(s, s->header.l1_table_offset)) { - return -EINVAL; - } - - s->table_nelems = (s->header.cluster_size * s->header.table_size) / - sizeof(uint64_t); - s->l2_shift = ctz32(s->header.cluster_size); - s->l2_mask = s->table_nelems - 1; - s->l1_shift = s->l2_shift + ctz32(s->table_nelems); - - /* Header size calculation must not overflow uint32_t */ - if (s->header.header_size > UINT32_MAX / s->header.cluster_size) { - return -EINVAL; - } - - if ((s->header.features & QED_F_BACKING_FILE)) { - if ((uint64_t)s->header.backing_filename_offset + - s->header.backing_filename_size > - s->header.cluster_size * s->header.header_size) { - return -EINVAL; - } - - ret = qed_read_string(bs->file->bs, s->header.backing_filename_offset, - s->header.backing_filename_size, bs->backing_file, - sizeof(bs->backing_file)); - if (ret < 0) { - return ret; - } - - if (s->header.features & QED_F_BACKING_FORMAT_NO_PROBE) { - pstrcpy(bs->backing_format, sizeof(bs->backing_format), "raw"); - } - } - - /* Reset unknown autoclear feature bits. This is a backwards - * compatibility mechanism that allows images to be opened by older - * programs, which "knock out" unknown feature bits. When an image is - * opened by a newer program again it can detect that the autoclear - * feature is no longer valid. - */ - if ((s->header.autoclear_features & ~QED_AUTOCLEAR_FEATURE_MASK) != 0 && - !bdrv_is_read_only(bs->file->bs) && !(flags & BDRV_O_INACTIVE)) { - s->header.autoclear_features &= QED_AUTOCLEAR_FEATURE_MASK; - - ret = qed_write_header_sync(s); - if (ret) { - return ret; - } - - /* From here on only known autoclear feature bits are valid */ - bdrv_flush(bs->file->bs); - } - - s->l1_table = qed_alloc_table(s); - qed_init_l2_cache(&s->l2_cache); - - ret = qed_read_l1_table_sync(s); - if (ret) { - goto out; - } - - /* If image was not closed cleanly, check consistency */ - if (!(flags & BDRV_O_CHECK) && (s->header.features & QED_F_NEED_CHECK)) { - /* Read-only images cannot be fixed. There is no risk of corruption - * since write operations are not possible. Therefore, allow - * potentially inconsistent images to be opened read-only. This can - * aid data recovery from an otherwise inconsistent image. - */ - if (!bdrv_is_read_only(bs->file->bs) && - !(flags & BDRV_O_INACTIVE)) { - BdrvCheckResult result = {0}; - - ret = qed_check(s, &result, true); - if (ret) { - goto out; - } - } - } - - bdrv_qed_attach_aio_context(bs, bdrv_get_aio_context(bs)); - -out: - if (ret) { - qed_free_l2_cache(&s->l2_cache); - qemu_vfree(s->l1_table); - } - return ret; -} - -static void bdrv_qed_refresh_limits(BlockDriverState *bs, Error **errp) -{ - BDRVQEDState *s = bs->opaque; - - bs->bl.write_zeroes_alignment = s->header.cluster_size >> BDRV_SECTOR_BITS; -} - -/* We have nothing to do for QED reopen, stubs just return - * success */ -static int bdrv_qed_reopen_prepare(BDRVReopenState *state, - BlockReopenQueue *queue, Error **errp) -{ - return 0; -} - -static void bdrv_qed_close(BlockDriverState *bs) -{ - BDRVQEDState *s = bs->opaque; - - bdrv_qed_detach_aio_context(bs); - - /* Ensure writes reach stable storage */ - bdrv_flush(bs->file->bs); - - /* Clean shutdown, no check required on next open */ - if (s->header.features & QED_F_NEED_CHECK) { - s->header.features &= ~QED_F_NEED_CHECK; - qed_write_header_sync(s); - } - - qed_free_l2_cache(&s->l2_cache); - qemu_vfree(s->l1_table); -} - -static int qed_create(const char *filename, uint32_t cluster_size, - uint64_t image_size, uint32_t table_size, - const char *backing_file, const char *backing_fmt, - QemuOpts *opts, Error **errp) -{ - QEDHeader header = { - .magic = QED_MAGIC, - .cluster_size = cluster_size, - .table_size = table_size, - .header_size = 1, - .features = 0, - .compat_features = 0, - .l1_table_offset = cluster_size, - .image_size = image_size, - }; - QEDHeader le_header; - uint8_t *l1_table = NULL; - size_t l1_size = header.cluster_size * header.table_size; - Error *local_err = NULL; - int ret = 0; - BlockBackend *blk; - - ret = bdrv_create_file(filename, opts, &local_err); - if (ret < 0) { - error_propagate(errp, local_err); - return ret; - } - - blk = blk_new_open(filename, NULL, NULL, - BDRV_O_RDWR | BDRV_O_PROTOCOL, &local_err); - if (blk == NULL) { - error_propagate(errp, local_err); - return -EIO; - } - - blk_set_allow_write_beyond_eof(blk, true); - - /* File must start empty and grow, check truncate is supported */ - ret = blk_truncate(blk, 0); - if (ret < 0) { - goto out; - } - - if (backing_file) { - header.features |= QED_F_BACKING_FILE; - header.backing_filename_offset = sizeof(le_header); - header.backing_filename_size = strlen(backing_file); - - if (qed_fmt_is_raw(backing_fmt)) { - header.features |= QED_F_BACKING_FORMAT_NO_PROBE; - } - } - - qed_header_cpu_to_le(&header, &le_header); - ret = blk_pwrite(blk, 0, &le_header, sizeof(le_header)); - if (ret < 0) { - goto out; - } - ret = blk_pwrite(blk, sizeof(le_header), backing_file, - header.backing_filename_size); - if (ret < 0) { - goto out; - } - - l1_table = g_malloc0(l1_size); - ret = blk_pwrite(blk, header.l1_table_offset, l1_table, l1_size); - if (ret < 0) { - goto out; - } - - ret = 0; /* success */ -out: - g_free(l1_table); - blk_unref(blk); - return ret; -} - -static int bdrv_qed_create(const char *filename, QemuOpts *opts, Error **errp) -{ - uint64_t image_size = 0; - uint32_t cluster_size = QED_DEFAULT_CLUSTER_SIZE; - uint32_t table_size = QED_DEFAULT_TABLE_SIZE; - char *backing_file = NULL; - char *backing_fmt = NULL; - int ret; - - image_size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0), - BDRV_SECTOR_SIZE); - backing_file = qemu_opt_get_del(opts, BLOCK_OPT_BACKING_FILE); - backing_fmt = qemu_opt_get_del(opts, BLOCK_OPT_BACKING_FMT); - cluster_size = qemu_opt_get_size_del(opts, - BLOCK_OPT_CLUSTER_SIZE, - QED_DEFAULT_CLUSTER_SIZE); - table_size = qemu_opt_get_size_del(opts, BLOCK_OPT_TABLE_SIZE, - QED_DEFAULT_TABLE_SIZE); - - if (!qed_is_cluster_size_valid(cluster_size)) { - error_setg(errp, "QED cluster size must be within range [%u, %u] " - "and power of 2", - QED_MIN_CLUSTER_SIZE, QED_MAX_CLUSTER_SIZE); - ret = -EINVAL; - goto finish; - } - if (!qed_is_table_size_valid(table_size)) { - error_setg(errp, "QED table size must be within range [%u, %u] " - "and power of 2", - QED_MIN_TABLE_SIZE, QED_MAX_TABLE_SIZE); - ret = -EINVAL; - goto finish; - } - if (!qed_is_image_size_valid(image_size, cluster_size, table_size)) { - error_setg(errp, "QED image size must be a non-zero multiple of " - "cluster size and less than %" PRIu64 " bytes", - qed_max_image_size(cluster_size, table_size)); - ret = -EINVAL; - goto finish; - } - - ret = qed_create(filename, cluster_size, image_size, table_size, - backing_file, backing_fmt, opts, errp); - -finish: - g_free(backing_file); - g_free(backing_fmt); - return ret; -} - -typedef struct { - BlockDriverState *bs; - Coroutine *co; - uint64_t pos; - int64_t status; - int *pnum; - BlockDriverState **file; -} QEDIsAllocatedCB; - -static void qed_is_allocated_cb(void *opaque, int ret, uint64_t offset, size_t len) -{ - QEDIsAllocatedCB *cb = opaque; - BDRVQEDState *s = cb->bs->opaque; - *cb->pnum = len / BDRV_SECTOR_SIZE; - switch (ret) { - case QED_CLUSTER_FOUND: - offset |= qed_offset_into_cluster(s, cb->pos); - cb->status = BDRV_BLOCK_DATA | BDRV_BLOCK_OFFSET_VALID | offset; - *cb->file = cb->bs->file->bs; - break; - case QED_CLUSTER_ZERO: - cb->status = BDRV_BLOCK_ZERO; - break; - case QED_CLUSTER_L2: - case QED_CLUSTER_L1: - cb->status = 0; - break; - default: - assert(ret < 0); - cb->status = ret; - break; - } - - if (cb->co) { - qemu_coroutine_enter(cb->co, NULL); - } -} - -static int64_t coroutine_fn bdrv_qed_co_get_block_status(BlockDriverState *bs, - int64_t sector_num, - int nb_sectors, int *pnum, - BlockDriverState **file) -{ - BDRVQEDState *s = bs->opaque; - size_t len = (size_t)nb_sectors * BDRV_SECTOR_SIZE; - QEDIsAllocatedCB cb = { - .bs = bs, - .pos = (uint64_t)sector_num * BDRV_SECTOR_SIZE, - .status = BDRV_BLOCK_OFFSET_MASK, - .pnum = pnum, - .file = file, - }; - QEDRequest request = { .l2_table = NULL }; - - qed_find_cluster(s, &request, cb.pos, len, qed_is_allocated_cb, &cb); - - /* Now sleep if the callback wasn't invoked immediately */ - while (cb.status == BDRV_BLOCK_OFFSET_MASK) { - cb.co = qemu_coroutine_self(); - qemu_coroutine_yield(); - } - - qed_unref_l2_cache_entry(request.l2_table); - - return cb.status; -} - -static BDRVQEDState *acb_to_s(QEDAIOCB *acb) -{ - return acb->common.bs->opaque; -} - -/** - * Read from the backing file or zero-fill if no backing file - * - * @s: QED state - * @pos: Byte position in device - * @qiov: Destination I/O vector - * @backing_qiov: Possibly shortened copy of qiov, to be allocated here - * @cb: Completion function - * @opaque: User data for completion function - * - * This function reads qiov->size bytes starting at pos from the backing file. - * If there is no backing file then zeroes are read. - */ -static void qed_read_backing_file(BDRVQEDState *s, uint64_t pos, - QEMUIOVector *qiov, - QEMUIOVector **backing_qiov, - BlockCompletionFunc *cb, void *opaque) -{ - uint64_t backing_length = 0; - size_t size; - - /* If there is a backing file, get its length. Treat the absence of a - * backing file like a zero length backing file. - */ - if (s->bs->backing) { - int64_t l = bdrv_getlength(s->bs->backing->bs); - if (l < 0) { - cb(opaque, l); - return; - } - backing_length = l; - } - - /* Zero all sectors if reading beyond the end of the backing file */ - if (pos >= backing_length || - pos + qiov->size > backing_length) { - qemu_iovec_memset(qiov, 0, 0, qiov->size); - } - - /* Complete now if there are no backing file sectors to read */ - if (pos >= backing_length) { - cb(opaque, 0); - return; - } - - /* If the read straddles the end of the backing file, shorten it */ - size = MIN((uint64_t)backing_length - pos, qiov->size); - - assert(*backing_qiov == NULL); - *backing_qiov = g_new(QEMUIOVector, 1); - qemu_iovec_init(*backing_qiov, qiov->niov); - qemu_iovec_concat(*backing_qiov, qiov, 0, size); - - BLKDBG_EVENT(s->bs->file, BLKDBG_READ_BACKING_AIO); - bdrv_aio_readv(s->bs->backing->bs, pos / BDRV_SECTOR_SIZE, - *backing_qiov, size / BDRV_SECTOR_SIZE, cb, opaque); -} - -typedef struct { - GenericCB gencb; - BDRVQEDState *s; - QEMUIOVector qiov; - QEMUIOVector *backing_qiov; - struct iovec iov; - uint64_t offset; -} CopyFromBackingFileCB; - -static void qed_copy_from_backing_file_cb(void *opaque, int ret) -{ - CopyFromBackingFileCB *copy_cb = opaque; - qemu_vfree(copy_cb->iov.iov_base); - gencb_complete(©_cb->gencb, ret); -} - -static void qed_copy_from_backing_file_write(void *opaque, int ret) -{ - CopyFromBackingFileCB *copy_cb = opaque; - BDRVQEDState *s = copy_cb->s; - - if (copy_cb->backing_qiov) { - qemu_iovec_destroy(copy_cb->backing_qiov); - g_free(copy_cb->backing_qiov); - copy_cb->backing_qiov = NULL; - } - - if (ret) { - qed_copy_from_backing_file_cb(copy_cb, ret); - return; - } - - BLKDBG_EVENT(s->bs->file, BLKDBG_COW_WRITE); - bdrv_aio_writev(s->bs->file->bs, copy_cb->offset / BDRV_SECTOR_SIZE, - ©_cb->qiov, copy_cb->qiov.size / BDRV_SECTOR_SIZE, - qed_copy_from_backing_file_cb, copy_cb); -} - -/** - * Copy data from backing file into the image - * - * @s: QED state - * @pos: Byte position in device - * @len: Number of bytes - * @offset: Byte offset in image file - * @cb: Completion function - * @opaque: User data for completion function - */ -static void qed_copy_from_backing_file(BDRVQEDState *s, uint64_t pos, - uint64_t len, uint64_t offset, - BlockCompletionFunc *cb, - void *opaque) -{ - CopyFromBackingFileCB *copy_cb; - - /* Skip copy entirely if there is no work to do */ - if (len == 0) { - cb(opaque, 0); - return; - } - - copy_cb = gencb_alloc(sizeof(*copy_cb), cb, opaque); - copy_cb->s = s; - copy_cb->offset = offset; - copy_cb->backing_qiov = NULL; - copy_cb->iov.iov_base = qemu_blockalign(s->bs, len); - copy_cb->iov.iov_len = len; - qemu_iovec_init_external(©_cb->qiov, ©_cb->iov, 1); - - qed_read_backing_file(s, pos, ©_cb->qiov, ©_cb->backing_qiov, - qed_copy_from_backing_file_write, copy_cb); -} - -/** - * Link one or more contiguous clusters into a table - * - * @s: QED state - * @table: L2 table - * @index: First cluster index - * @n: Number of contiguous clusters - * @cluster: First cluster offset - * - * The cluster offset may be an allocated byte offset in the image file, the - * zero cluster marker, or the unallocated cluster marker. - */ -static void qed_update_l2_table(BDRVQEDState *s, QEDTable *table, int index, - unsigned int n, uint64_t cluster) -{ - int i; - for (i = index; i < index + n; i++) { - table->offsets[i] = cluster; - if (!qed_offset_is_unalloc_cluster(cluster) && - !qed_offset_is_zero_cluster(cluster)) { - cluster += s->header.cluster_size; - } - } -} - -static void qed_aio_complete_bh(void *opaque) -{ - QEDAIOCB *acb = opaque; - BlockCompletionFunc *cb = acb->common.cb; - void *user_opaque = acb->common.opaque; - int ret = acb->bh_ret; - - qemu_bh_delete(acb->bh); - qemu_aio_unref(acb); - - /* Invoke callback */ - cb(user_opaque, ret); -} - -static void qed_aio_complete(QEDAIOCB *acb, int ret) -{ - BDRVQEDState *s = acb_to_s(acb); - - trace_qed_aio_complete(s, acb, ret); - - /* Free resources */ - qemu_iovec_destroy(&acb->cur_qiov); - qed_unref_l2_cache_entry(acb->request.l2_table); - - /* Free the buffer we may have allocated for zero writes */ - if (acb->flags & QED_AIOCB_ZERO) { - qemu_vfree(acb->qiov->iov[0].iov_base); - acb->qiov->iov[0].iov_base = NULL; - } - - /* Arrange for a bh to invoke the completion function */ - acb->bh_ret = ret; - acb->bh = aio_bh_new(bdrv_get_aio_context(acb->common.bs), - qed_aio_complete_bh, acb); - qemu_bh_schedule(acb->bh); - - /* Start next allocating write request waiting behind this one. Note that - * requests enqueue themselves when they first hit an unallocated cluster - * but they wait until the entire request is finished before waking up the - * next request in the queue. This ensures that we don't cycle through - * requests multiple times but rather finish one at a time completely. - */ - if (acb == QSIMPLEQ_FIRST(&s->allocating_write_reqs)) { - QSIMPLEQ_REMOVE_HEAD(&s->allocating_write_reqs, next); - acb = QSIMPLEQ_FIRST(&s->allocating_write_reqs); - if (acb) { - qed_aio_next_io(acb, 0); - } else if (s->header.features & QED_F_NEED_CHECK) { - qed_start_need_check_timer(s); - } - } -} - -/** - * Commit the current L2 table to the cache - */ -static void qed_commit_l2_update(void *opaque, int ret) -{ - QEDAIOCB *acb = opaque; - BDRVQEDState *s = acb_to_s(acb); - CachedL2Table *l2_table = acb->request.l2_table; - uint64_t l2_offset = l2_table->offset; - - qed_commit_l2_cache_entry(&s->l2_cache, l2_table); - - /* This is guaranteed to succeed because we just committed the entry to the - * cache. - */ - acb->request.l2_table = qed_find_l2_cache_entry(&s->l2_cache, l2_offset); - assert(acb->request.l2_table != NULL); - - qed_aio_next_io(opaque, ret); -} - -/** - * Update L1 table with new L2 table offset and write it out - */ -static void qed_aio_write_l1_update(void *opaque, int ret) -{ - QEDAIOCB *acb = opaque; - BDRVQEDState *s = acb_to_s(acb); - int index; - - if (ret) { - qed_aio_complete(acb, ret); - return; - } - - index = qed_l1_index(s, acb->cur_pos); - s->l1_table->offsets[index] = acb->request.l2_table->offset; - - qed_write_l1_table(s, index, 1, qed_commit_l2_update, acb); -} - -/** - * Update L2 table with new cluster offsets and write them out - */ -static void qed_aio_write_l2_update(QEDAIOCB *acb, int ret, uint64_t offset) -{ - BDRVQEDState *s = acb_to_s(acb); - bool need_alloc = acb->find_cluster_ret == QED_CLUSTER_L1; - int index; - - if (ret) { - goto err; - } - - if (need_alloc) { - qed_unref_l2_cache_entry(acb->request.l2_table); - acb->request.l2_table = qed_new_l2_table(s); - } - - index = qed_l2_index(s, acb->cur_pos); - qed_update_l2_table(s, acb->request.l2_table->table, index, acb->cur_nclusters, - offset); - - if (need_alloc) { - /* Write out the whole new L2 table */ - qed_write_l2_table(s, &acb->request, 0, s->table_nelems, true, - qed_aio_write_l1_update, acb); - } else { - /* Write out only the updated part of the L2 table */ - qed_write_l2_table(s, &acb->request, index, acb->cur_nclusters, false, - qed_aio_next_io, acb); - } - return; - -err: - qed_aio_complete(acb, ret); -} - -static void qed_aio_write_l2_update_cb(void *opaque, int ret) -{ - QEDAIOCB *acb = opaque; - qed_aio_write_l2_update(acb, ret, acb->cur_cluster); -} - -/** - * Flush new data clusters before updating the L2 table - * - * This flush is necessary when a backing file is in use. A crash during an - * allocating write could result in empty clusters in the image. If the write - * only touched a subregion of the cluster, then backing image sectors have - * been lost in the untouched region. The solution is to flush after writing a - * new data cluster and before updating the L2 table. - */ -static void qed_aio_write_flush_before_l2_update(void *opaque, int ret) -{ - QEDAIOCB *acb = opaque; - BDRVQEDState *s = acb_to_s(acb); - - if (!bdrv_aio_flush(s->bs->file->bs, qed_aio_write_l2_update_cb, opaque)) { - qed_aio_complete(acb, -EIO); - } -} - -/** - * Write data to the image file - */ -static void qed_aio_write_main(void *opaque, int ret) -{ - QEDAIOCB *acb = opaque; - BDRVQEDState *s = acb_to_s(acb); - uint64_t offset = acb->cur_cluster + - qed_offset_into_cluster(s, acb->cur_pos); - BlockCompletionFunc *next_fn; - - trace_qed_aio_write_main(s, acb, ret, offset, acb->cur_qiov.size); - - if (ret) { - qed_aio_complete(acb, ret); - return; - } - - if (acb->find_cluster_ret == QED_CLUSTER_FOUND) { - next_fn = qed_aio_next_io; - } else { - if (s->bs->backing) { - next_fn = qed_aio_write_flush_before_l2_update; - } else { - next_fn = qed_aio_write_l2_update_cb; - } - } - - BLKDBG_EVENT(s->bs->file, BLKDBG_WRITE_AIO); - bdrv_aio_writev(s->bs->file->bs, offset / BDRV_SECTOR_SIZE, - &acb->cur_qiov, acb->cur_qiov.size / BDRV_SECTOR_SIZE, - next_fn, acb); -} - -/** - * Populate back untouched region of new data cluster - */ -static void qed_aio_write_postfill(void *opaque, int ret) -{ - QEDAIOCB *acb = opaque; - BDRVQEDState *s = acb_to_s(acb); - uint64_t start = acb->cur_pos + acb->cur_qiov.size; - uint64_t len = - qed_start_of_cluster(s, start + s->header.cluster_size - 1) - start; - uint64_t offset = acb->cur_cluster + - qed_offset_into_cluster(s, acb->cur_pos) + - acb->cur_qiov.size; - - if (ret) { - qed_aio_complete(acb, ret); - return; - } - - trace_qed_aio_write_postfill(s, acb, start, len, offset); - qed_copy_from_backing_file(s, start, len, offset, - qed_aio_write_main, acb); -} - -/** - * Populate front untouched region of new data cluster - */ -static void qed_aio_write_prefill(void *opaque, int ret) -{ - QEDAIOCB *acb = opaque; - BDRVQEDState *s = acb_to_s(acb); - uint64_t start = qed_start_of_cluster(s, acb->cur_pos); - uint64_t len = qed_offset_into_cluster(s, acb->cur_pos); - - trace_qed_aio_write_prefill(s, acb, start, len, acb->cur_cluster); - qed_copy_from_backing_file(s, start, len, acb->cur_cluster, - qed_aio_write_postfill, acb); -} - -/** - * Check if the QED_F_NEED_CHECK bit should be set during allocating write - */ -static bool qed_should_set_need_check(BDRVQEDState *s) -{ - /* The flush before L2 update path ensures consistency */ - if (s->bs->backing) { - return false; - } - - return !(s->header.features & QED_F_NEED_CHECK); -} - -static void qed_aio_write_zero_cluster(void *opaque, int ret) -{ - QEDAIOCB *acb = opaque; - - if (ret) { - qed_aio_complete(acb, ret); - return; - } - - qed_aio_write_l2_update(acb, 0, 1); -} - -/** - * Write new data cluster - * - * @acb: Write request - * @len: Length in bytes - * - * This path is taken when writing to previously unallocated clusters. - */ -static void qed_aio_write_alloc(QEDAIOCB *acb, size_t len) -{ - BDRVQEDState *s = acb_to_s(acb); - BlockCompletionFunc *cb; - - /* Cancel timer when the first allocating request comes in */ - if (QSIMPLEQ_EMPTY(&s->allocating_write_reqs)) { - qed_cancel_need_check_timer(s); - } - - /* Freeze this request if another allocating write is in progress */ - if (acb != QSIMPLEQ_FIRST(&s->allocating_write_reqs)) { - QSIMPLEQ_INSERT_TAIL(&s->allocating_write_reqs, acb, next); - } - if (acb != QSIMPLEQ_FIRST(&s->allocating_write_reqs) || - s->allocating_write_reqs_plugged) { - return; /* wait for existing request to finish */ - } - - acb->cur_nclusters = qed_bytes_to_clusters(s, - qed_offset_into_cluster(s, acb->cur_pos) + len); - qemu_iovec_concat(&acb->cur_qiov, acb->qiov, acb->qiov_offset, len); - - if (acb->flags & QED_AIOCB_ZERO) { - /* Skip ahead if the clusters are already zero */ - if (acb->find_cluster_ret == QED_CLUSTER_ZERO) { - qed_aio_next_io(acb, 0); - return; - } - - cb = qed_aio_write_zero_cluster; - } else { - cb = qed_aio_write_prefill; - acb->cur_cluster = qed_alloc_clusters(s, acb->cur_nclusters); - } - - if (qed_should_set_need_check(s)) { - s->header.features |= QED_F_NEED_CHECK; - qed_write_header(s, cb, acb); - } else { - cb(acb, 0); - } -} - -/** - * Write data cluster in place - * - * @acb: Write request - * @offset: Cluster offset in bytes - * @len: Length in bytes - * - * This path is taken when writing to already allocated clusters. - */ -static void qed_aio_write_inplace(QEDAIOCB *acb, uint64_t offset, size_t len) -{ - /* Allocate buffer for zero writes */ - if (acb->flags & QED_AIOCB_ZERO) { - struct iovec *iov = acb->qiov->iov; - - if (!iov->iov_base) { - iov->iov_base = qemu_try_blockalign(acb->common.bs, iov->iov_len); - if (iov->iov_base == NULL) { - qed_aio_complete(acb, -ENOMEM); - return; - } - memset(iov->iov_base, 0, iov->iov_len); - } - } - - /* Calculate the I/O vector */ - acb->cur_cluster = offset; - qemu_iovec_concat(&acb->cur_qiov, acb->qiov, acb->qiov_offset, len); - - /* Do the actual write */ - qed_aio_write_main(acb, 0); -} - -/** - * Write data cluster - * - * @opaque: Write request - * @ret: QED_CLUSTER_FOUND, QED_CLUSTER_L2, QED_CLUSTER_L1, - * or -errno - * @offset: Cluster offset in bytes - * @len: Length in bytes - * - * Callback from qed_find_cluster(). - */ -static void qed_aio_write_data(void *opaque, int ret, - uint64_t offset, size_t len) -{ - QEDAIOCB *acb = opaque; - - trace_qed_aio_write_data(acb_to_s(acb), acb, ret, offset, len); - - acb->find_cluster_ret = ret; - - switch (ret) { - case QED_CLUSTER_FOUND: - qed_aio_write_inplace(acb, offset, len); - break; - - case QED_CLUSTER_L2: - case QED_CLUSTER_L1: - case QED_CLUSTER_ZERO: - qed_aio_write_alloc(acb, len); - break; - - default: - qed_aio_complete(acb, ret); - break; - } -} - -/** - * Read data cluster - * - * @opaque: Read request - * @ret: QED_CLUSTER_FOUND, QED_CLUSTER_L2, QED_CLUSTER_L1, - * or -errno - * @offset: Cluster offset in bytes - * @len: Length in bytes - * - * Callback from qed_find_cluster(). - */ -static void qed_aio_read_data(void *opaque, int ret, - uint64_t offset, size_t len) -{ - QEDAIOCB *acb = opaque; - BDRVQEDState *s = acb_to_s(acb); - BlockDriverState *bs = acb->common.bs; - - /* Adjust offset into cluster */ - offset += qed_offset_into_cluster(s, acb->cur_pos); - - trace_qed_aio_read_data(s, acb, ret, offset, len); - - if (ret < 0) { - goto err; - } - - qemu_iovec_concat(&acb->cur_qiov, acb->qiov, acb->qiov_offset, len); - - /* Handle zero cluster and backing file reads */ - if (ret == QED_CLUSTER_ZERO) { - qemu_iovec_memset(&acb->cur_qiov, 0, 0, acb->cur_qiov.size); - qed_aio_next_io(acb, 0); - return; - } else if (ret != QED_CLUSTER_FOUND) { - qed_read_backing_file(s, acb->cur_pos, &acb->cur_qiov, - &acb->backing_qiov, qed_aio_next_io, acb); - return; - } - - BLKDBG_EVENT(bs->file, BLKDBG_READ_AIO); - bdrv_aio_readv(bs->file->bs, offset / BDRV_SECTOR_SIZE, - &acb->cur_qiov, acb->cur_qiov.size / BDRV_SECTOR_SIZE, - qed_aio_next_io, acb); - return; - -err: - qed_aio_complete(acb, ret); -} - -/** - * Begin next I/O or complete the request - */ -static void qed_aio_next_io(void *opaque, int ret) -{ - QEDAIOCB *acb = opaque; - BDRVQEDState *s = acb_to_s(acb); - QEDFindClusterFunc *io_fn = (acb->flags & QED_AIOCB_WRITE) ? - qed_aio_write_data : qed_aio_read_data; - - trace_qed_aio_next_io(s, acb, ret, acb->cur_pos + acb->cur_qiov.size); - - if (acb->backing_qiov) { - qemu_iovec_destroy(acb->backing_qiov); - g_free(acb->backing_qiov); - acb->backing_qiov = NULL; - } - - /* Handle I/O error */ - if (ret) { - qed_aio_complete(acb, ret); - return; - } - - acb->qiov_offset += acb->cur_qiov.size; - acb->cur_pos += acb->cur_qiov.size; - qemu_iovec_reset(&acb->cur_qiov); - - /* Complete request */ - if (acb->cur_pos >= acb->end_pos) { - qed_aio_complete(acb, 0); - return; - } - - /* Find next cluster and start I/O */ - qed_find_cluster(s, &acb->request, - acb->cur_pos, acb->end_pos - acb->cur_pos, - io_fn, acb); -} - -static BlockAIOCB *qed_aio_setup(BlockDriverState *bs, - int64_t sector_num, - QEMUIOVector *qiov, int nb_sectors, - BlockCompletionFunc *cb, - void *opaque, int flags) -{ - QEDAIOCB *acb = qemu_aio_get(&qed_aiocb_info, bs, cb, opaque); - - trace_qed_aio_setup(bs->opaque, acb, sector_num, nb_sectors, - opaque, flags); - - acb->flags = flags; - acb->qiov = qiov; - acb->qiov_offset = 0; - acb->cur_pos = (uint64_t)sector_num * BDRV_SECTOR_SIZE; - acb->end_pos = acb->cur_pos + nb_sectors * BDRV_SECTOR_SIZE; - acb->backing_qiov = NULL; - acb->request.l2_table = NULL; - qemu_iovec_init(&acb->cur_qiov, qiov->niov); - - /* Start request */ - qed_aio_next_io(acb, 0); - return &acb->common; -} - -static BlockAIOCB *bdrv_qed_aio_readv(BlockDriverState *bs, - int64_t sector_num, - QEMUIOVector *qiov, int nb_sectors, - BlockCompletionFunc *cb, - void *opaque) -{ - return qed_aio_setup(bs, sector_num, qiov, nb_sectors, cb, opaque, 0); -} - -static BlockAIOCB *bdrv_qed_aio_writev(BlockDriverState *bs, - int64_t sector_num, - QEMUIOVector *qiov, int nb_sectors, - BlockCompletionFunc *cb, - void *opaque) -{ - return qed_aio_setup(bs, sector_num, qiov, nb_sectors, cb, - opaque, QED_AIOCB_WRITE); -} - -typedef struct { - Coroutine *co; - int ret; - bool done; -} QEDWriteZeroesCB; - -static void coroutine_fn qed_co_write_zeroes_cb(void *opaque, int ret) -{ - QEDWriteZeroesCB *cb = opaque; - - cb->done = true; - cb->ret = ret; - if (cb->co) { - qemu_coroutine_enter(cb->co, NULL); - } -} - -static int coroutine_fn bdrv_qed_co_write_zeroes(BlockDriverState *bs, - int64_t sector_num, - int nb_sectors, - BdrvRequestFlags flags) -{ - BlockAIOCB *blockacb; - BDRVQEDState *s = bs->opaque; - QEDWriteZeroesCB cb = { .done = false }; - QEMUIOVector qiov; - struct iovec iov; - - /* Refuse if there are untouched backing file sectors */ - if (bs->backing) { - if (qed_offset_into_cluster(s, sector_num * BDRV_SECTOR_SIZE) != 0) { - return -ENOTSUP; - } - if (qed_offset_into_cluster(s, nb_sectors * BDRV_SECTOR_SIZE) != 0) { - return -ENOTSUP; - } - } - - /* Zero writes start without an I/O buffer. If a buffer becomes necessary - * then it will be allocated during request processing. - */ - iov.iov_base = NULL, - iov.iov_len = nb_sectors * BDRV_SECTOR_SIZE, - - qemu_iovec_init_external(&qiov, &iov, 1); - blockacb = qed_aio_setup(bs, sector_num, &qiov, nb_sectors, - qed_co_write_zeroes_cb, &cb, - QED_AIOCB_WRITE | QED_AIOCB_ZERO); - if (!blockacb) { - return -EIO; - } - if (!cb.done) { - cb.co = qemu_coroutine_self(); - qemu_coroutine_yield(); - } - assert(cb.done); - return cb.ret; -} - -static int bdrv_qed_truncate(BlockDriverState *bs, int64_t offset) -{ - BDRVQEDState *s = bs->opaque; - uint64_t old_image_size; - int ret; - - if (!qed_is_image_size_valid(offset, s->header.cluster_size, - s->header.table_size)) { - return -EINVAL; - } - - /* Shrinking is currently not supported */ - if ((uint64_t)offset < s->header.image_size) { - return -ENOTSUP; - } - - old_image_size = s->header.image_size; - s->header.image_size = offset; - ret = qed_write_header_sync(s); - if (ret < 0) { - s->header.image_size = old_image_size; - } - return ret; -} - -static int64_t bdrv_qed_getlength(BlockDriverState *bs) -{ - BDRVQEDState *s = bs->opaque; - return s->header.image_size; -} - -static int bdrv_qed_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) -{ - BDRVQEDState *s = bs->opaque; - - memset(bdi, 0, sizeof(*bdi)); - bdi->cluster_size = s->header.cluster_size; - bdi->is_dirty = s->header.features & QED_F_NEED_CHECK; - bdi->unallocated_blocks_are_zero = true; - bdi->can_write_zeroes_with_unmap = true; - return 0; -} - -static int bdrv_qed_change_backing_file(BlockDriverState *bs, - const char *backing_file, - const char *backing_fmt) -{ - BDRVQEDState *s = bs->opaque; - QEDHeader new_header, le_header; - void *buffer; - size_t buffer_len, backing_file_len; - int ret; - - /* Refuse to set backing filename if unknown compat feature bits are - * active. If the image uses an unknown compat feature then we may not - * know the layout of data following the header structure and cannot safely - * add a new string. - */ - if (backing_file && (s->header.compat_features & - ~QED_COMPAT_FEATURE_MASK)) { - return -ENOTSUP; - } - - memcpy(&new_header, &s->header, sizeof(new_header)); - - new_header.features &= ~(QED_F_BACKING_FILE | - QED_F_BACKING_FORMAT_NO_PROBE); - - /* Adjust feature flags */ - if (backing_file) { - new_header.features |= QED_F_BACKING_FILE; - - if (qed_fmt_is_raw(backing_fmt)) { - new_header.features |= QED_F_BACKING_FORMAT_NO_PROBE; - } - } - - /* Calculate new header size */ - backing_file_len = 0; - - if (backing_file) { - backing_file_len = strlen(backing_file); - } - - buffer_len = sizeof(new_header); - new_header.backing_filename_offset = buffer_len; - new_header.backing_filename_size = backing_file_len; - buffer_len += backing_file_len; - - /* Make sure we can rewrite header without failing */ - if (buffer_len > new_header.header_size * new_header.cluster_size) { - return -ENOSPC; - } - - /* Prepare new header */ - buffer = g_malloc(buffer_len); - - qed_header_cpu_to_le(&new_header, &le_header); - memcpy(buffer, &le_header, sizeof(le_header)); - buffer_len = sizeof(le_header); - - if (backing_file) { - memcpy(buffer + buffer_len, backing_file, backing_file_len); - buffer_len += backing_file_len; - } - - /* Write new header */ - ret = bdrv_pwrite_sync(bs->file->bs, 0, buffer, buffer_len); - g_free(buffer); - if (ret == 0) { - memcpy(&s->header, &new_header, sizeof(new_header)); - } - return ret; -} - -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_invalidate_cache(bs->file->bs, &local_err); - if (local_err) { - error_propagate(errp, local_err); - return; - } - - memset(s, 0, sizeof(BDRVQEDState)); - ret = bdrv_qed_open(bs, NULL, bs->open_flags, &local_err); - if (local_err) { - error_propagate(errp, local_err); - error_prepend(errp, "Could not reopen qed layer: "); - return; - } else if (ret < 0) { - error_setg_errno(errp, -ret, "Could not reopen qed layer"); - return; - } -} - -static int bdrv_qed_check(BlockDriverState *bs, BdrvCheckResult *result, - BdrvCheckMode fix) -{ - BDRVQEDState *s = bs->opaque; - - return qed_check(s, result, !!fix); -} - -static QemuOptsList qed_create_opts = { - .name = "qed-create-opts", - .head = QTAILQ_HEAD_INITIALIZER(qed_create_opts.head), - .desc = { - { - .name = BLOCK_OPT_SIZE, - .type = QEMU_OPT_SIZE, - .help = "Virtual disk size" - }, - { - .name = BLOCK_OPT_BACKING_FILE, - .type = QEMU_OPT_STRING, - .help = "File name of a base image" - }, - { - .name = BLOCK_OPT_BACKING_FMT, - .type = QEMU_OPT_STRING, - .help = "Image format of the base image" - }, - { - .name = BLOCK_OPT_CLUSTER_SIZE, - .type = QEMU_OPT_SIZE, - .help = "Cluster size (in bytes)", - .def_value_str = stringify(QED_DEFAULT_CLUSTER_SIZE) - }, - { - .name = BLOCK_OPT_TABLE_SIZE, - .type = QEMU_OPT_SIZE, - .help = "L1/L2 table size (in clusters)" - }, - { /* end of list */ } - } -}; - -static BlockDriver bdrv_qed = { - .format_name = "qed", - .instance_size = sizeof(BDRVQEDState), - .create_opts = &qed_create_opts, - .supports_backing = true, - - .bdrv_probe = bdrv_qed_probe, - .bdrv_open = bdrv_qed_open, - .bdrv_close = bdrv_qed_close, - .bdrv_reopen_prepare = bdrv_qed_reopen_prepare, - .bdrv_create = bdrv_qed_create, - .bdrv_has_zero_init = bdrv_has_zero_init_1, - .bdrv_co_get_block_status = bdrv_qed_co_get_block_status, - .bdrv_aio_readv = bdrv_qed_aio_readv, - .bdrv_aio_writev = bdrv_qed_aio_writev, - .bdrv_co_write_zeroes = bdrv_qed_co_write_zeroes, - .bdrv_truncate = bdrv_qed_truncate, - .bdrv_getlength = bdrv_qed_getlength, - .bdrv_get_info = bdrv_qed_get_info, - .bdrv_refresh_limits = bdrv_qed_refresh_limits, - .bdrv_change_backing_file = bdrv_qed_change_backing_file, - .bdrv_invalidate_cache = bdrv_qed_invalidate_cache, - .bdrv_check = bdrv_qed_check, - .bdrv_detach_aio_context = bdrv_qed_detach_aio_context, - .bdrv_attach_aio_context = bdrv_qed_attach_aio_context, -}; - -static void bdrv_qed_init(void) -{ - bdrv_register(&bdrv_qed); -} - -block_init(bdrv_qed_init); |