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-rw-r--r--contrib/qemu/block/qed.c1596
1 files changed, 0 insertions, 1596 deletions
diff --git a/contrib/qemu/block/qed.c b/contrib/qemu/block/qed.c
deleted file mode 100644
index f767b0528ce..00000000000
--- a/contrib/qemu/block/qed.c
+++ /dev/null
@@ -1,1596 +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/timer.h"
-#include "trace.h"
-#include "qed.h"
-#include "qapi/qmp/qerror.h"
-#include "migration/migration.h"
-
-static void qed_aio_cancel(BlockDriverAIOCB *blockacb)
-{
- QEDAIOCB *acb = (QEDAIOCB *)blockacb;
- bool finished = false;
-
- /* Wait for the request to finish */
- acb->finished = &finished;
- while (!finished) {
- qemu_aio_wait();
- }
-}
-
-static const AIOCBInfo qed_aiocb_info = {
- .aiocb_size = sizeof(QEDAIOCB),
- .cancel = qed_aio_cancel,
-};
-
-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, 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, 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, BlockDriverCompletionFunc 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, 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 vm_clock so we don't alter the image file while suspended for
- * migration.
- */
- qemu_mod_timer(s->need_check_timer, qemu_get_clock_ns(vm_clock) +
- get_ticks_per_sec() * 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);
- qemu_del_timer(s->need_check_timer);
-}
-
-static void bdrv_qed_rebind(BlockDriverState *bs)
-{
- BDRVQEDState *s = bs->opaque;
- s->bs = bs;
-}
-
-static int bdrv_qed_open(BlockDriverState *bs, QDict *options, int flags)
-{
- 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, 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) {
- return -EMEDIUMTYPE;
- }
- if (s->header.features & ~QED_FEATURE_MASK) {
- /* image uses unsupported feature bits */
- char buf[64];
- snprintf(buf, sizeof(buf), "%" PRIx64,
- s->header.features & ~QED_FEATURE_MASK);
- qerror_report(QERR_UNKNOWN_BLOCK_FORMAT_FEATURE,
- bs->device_name, "QED", buf);
- 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);
- 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 = ffs(s->header.cluster_size) - 1;
- s->l2_mask = s->table_nelems - 1;
- s->l1_shift = s->l2_shift + ffs(s->table_nelems) - 1;
-
- 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, 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) && !(flags & BDRV_O_INCOMING)) {
- 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);
- }
-
- 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) &&
- !(flags & BDRV_O_INCOMING)) {
- BdrvCheckResult result = {0};
-
- ret = qed_check(s, &result, true);
- if (ret) {
- goto out;
- }
- }
- }
-
- s->need_check_timer = qemu_new_timer_ns(vm_clock,
- qed_need_check_timer_cb, s);
-
-out:
- if (ret) {
- qed_free_l2_cache(&s->l2_cache);
- qemu_vfree(s->l1_table);
- }
- return ret;
-}
-
-/* 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;
-
- qed_cancel_need_check_timer(s);
- qemu_free_timer(s->need_check_timer);
-
- /* Ensure writes reach stable storage */
- bdrv_flush(bs->file);
-
- /* 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)
-{
- 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;
- int ret = 0;
- BlockDriverState *bs = NULL;
-
- ret = bdrv_create_file(filename, NULL);
- if (ret < 0) {
- return ret;
- }
-
- ret = bdrv_file_open(&bs, filename, NULL, BDRV_O_RDWR | BDRV_O_CACHE_WB);
- if (ret < 0) {
- return ret;
- }
-
- /* File must start empty and grow, check truncate is supported */
- ret = bdrv_truncate(bs, 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 = bdrv_pwrite(bs, 0, &le_header, sizeof(le_header));
- if (ret < 0) {
- goto out;
- }
- ret = bdrv_pwrite(bs, sizeof(le_header), backing_file,
- header.backing_filename_size);
- if (ret < 0) {
- goto out;
- }
-
- l1_table = g_malloc0(l1_size);
- ret = bdrv_pwrite(bs, header.l1_table_offset, l1_table, l1_size);
- if (ret < 0) {
- goto out;
- }
-
- ret = 0; /* success */
-out:
- g_free(l1_table);
- bdrv_delete(bs);
- return ret;
-}
-
-static int bdrv_qed_create(const char *filename, QEMUOptionParameter *options)
-{
- uint64_t image_size = 0;
- uint32_t cluster_size = QED_DEFAULT_CLUSTER_SIZE;
- uint32_t table_size = QED_DEFAULT_TABLE_SIZE;
- const char *backing_file = NULL;
- const char *backing_fmt = NULL;
-
- while (options && options->name) {
- if (!strcmp(options->name, BLOCK_OPT_SIZE)) {
- image_size = options->value.n;
- } else if (!strcmp(options->name, BLOCK_OPT_BACKING_FILE)) {
- backing_file = options->value.s;
- } else if (!strcmp(options->name, BLOCK_OPT_BACKING_FMT)) {
- backing_fmt = options->value.s;
- } else if (!strcmp(options->name, BLOCK_OPT_CLUSTER_SIZE)) {
- if (options->value.n) {
- cluster_size = options->value.n;
- }
- } else if (!strcmp(options->name, BLOCK_OPT_TABLE_SIZE)) {
- if (options->value.n) {
- table_size = options->value.n;
- }
- }
- options++;
- }
-
- if (!qed_is_cluster_size_valid(cluster_size)) {
- fprintf(stderr, "QED cluster size must be within range [%u, %u] and power of 2\n",
- QED_MIN_CLUSTER_SIZE, QED_MAX_CLUSTER_SIZE);
- return -EINVAL;
- }
- if (!qed_is_table_size_valid(table_size)) {
- fprintf(stderr, "QED table size must be within range [%u, %u] and power of 2\n",
- QED_MIN_TABLE_SIZE, QED_MAX_TABLE_SIZE);
- return -EINVAL;
- }
- if (!qed_is_image_size_valid(image_size, cluster_size, table_size)) {
- fprintf(stderr, "QED image size must be a non-zero multiple of "
- "cluster size and less than %" PRIu64 " bytes\n",
- qed_max_image_size(cluster_size, table_size));
- return -EINVAL;
- }
-
- return qed_create(filename, cluster_size, image_size, table_size,
- backing_file, backing_fmt);
-}
-
-typedef struct {
- Coroutine *co;
- int is_allocated;
- int *pnum;
-} QEDIsAllocatedCB;
-
-static void qed_is_allocated_cb(void *opaque, int ret, uint64_t offset, size_t len)
-{
- QEDIsAllocatedCB *cb = opaque;
- *cb->pnum = len / BDRV_SECTOR_SIZE;
- cb->is_allocated = (ret == QED_CLUSTER_FOUND || ret == QED_CLUSTER_ZERO);
- if (cb->co) {
- qemu_coroutine_enter(cb->co, NULL);
- }
-}
-
-static int coroutine_fn bdrv_qed_co_is_allocated(BlockDriverState *bs,
- int64_t sector_num,
- int nb_sectors, int *pnum)
-{
- BDRVQEDState *s = bs->opaque;
- uint64_t pos = (uint64_t)sector_num * BDRV_SECTOR_SIZE;
- size_t len = (size_t)nb_sectors * BDRV_SECTOR_SIZE;
- QEDIsAllocatedCB cb = {
- .is_allocated = -1,
- .pnum = pnum,
- };
- QEDRequest request = { .l2_table = NULL };
-
- qed_find_cluster(s, &request, pos, len, qed_is_allocated_cb, &cb);
-
- /* Now sleep if the callback wasn't invoked immediately */
- while (cb.is_allocated == -1) {
- cb.co = qemu_coroutine_self();
- qemu_coroutine_yield();
- }
-
- qed_unref_l2_cache_entry(request.l2_table);
-
- return cb.is_allocated;
-}
-
-static int bdrv_qed_make_empty(BlockDriverState *bs)
-{
- return -ENOTSUP;
-}
-
-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
- * @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,
- BlockDriverCompletionFunc *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_hd) {
- int64_t l = bdrv_getlength(s->bs->backing_hd);
- 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);
-
- BLKDBG_EVENT(s->bs->file, BLKDBG_READ_BACKING_AIO);
- bdrv_aio_readv(s->bs->backing_hd, pos / BDRV_SECTOR_SIZE,
- qiov, size / BDRV_SECTOR_SIZE, cb, opaque);
-}
-
-typedef struct {
- GenericCB gencb;
- BDRVQEDState *s;
- QEMUIOVector 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(&copy_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 (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, copy_cb->offset / BDRV_SECTOR_SIZE,
- &copy_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,
- BlockDriverCompletionFunc *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->iov.iov_base = qemu_blockalign(s->bs, len);
- copy_cb->iov.iov_len = len;
- qemu_iovec_init_external(&copy_cb->qiov, &copy_cb->iov, 1);
-
- qed_read_backing_file(s, pos, &copy_cb->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;
- BlockDriverCompletionFunc *cb = acb->common.cb;
- void *user_opaque = acb->common.opaque;
- int ret = acb->bh_ret;
- bool *finished = acb->finished;
-
- qemu_bh_delete(acb->bh);
- qemu_aio_release(acb);
-
- /* Invoke callback */
- cb(user_opaque, ret);
-
- /* Signal cancel completion */
- if (finished) {
- *finished = true;
- }
-}
-
-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 = qemu_bh_new(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, 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);
- BlockDriverCompletionFunc *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_hd) {
- 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, 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_hd) {
- 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);
- BlockDriverCompletionFunc *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_blockalign(acb->common.bs, iov->iov_len);
- 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,
- qed_aio_next_io, acb);
- return;
- }
-
- BLKDBG_EVENT(bs->file, BLKDBG_READ_AIO);
- bdrv_aio_readv(bs->file, 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);
-
- /* 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 BlockDriverAIOCB *qed_aio_setup(BlockDriverState *bs,
- int64_t sector_num,
- QEMUIOVector *qiov, int nb_sectors,
- BlockDriverCompletionFunc *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->finished = NULL;
- 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->request.l2_table = NULL;
- qemu_iovec_init(&acb->cur_qiov, qiov->niov);
-
- /* Start request */
- qed_aio_next_io(acb, 0);
- return &acb->common;
-}
-
-static BlockDriverAIOCB *bdrv_qed_aio_readv(BlockDriverState *bs,
- int64_t sector_num,
- QEMUIOVector *qiov, int nb_sectors,
- BlockDriverCompletionFunc *cb,
- void *opaque)
-{
- return qed_aio_setup(bs, sector_num, qiov, nb_sectors, cb, opaque, 0);
-}
-
-static BlockDriverAIOCB *bdrv_qed_aio_writev(BlockDriverState *bs,
- int64_t sector_num,
- QEMUIOVector *qiov, int nb_sectors,
- BlockDriverCompletionFunc *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)
-{
- BlockDriverAIOCB *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_hd) {
- 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;
- 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, 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)
-{
- BDRVQEDState *s = bs->opaque;
-
- bdrv_qed_close(bs);
- memset(s, 0, sizeof(BDRVQEDState));
- bdrv_qed_open(bs, NULL, bs->open_flags);
-}
-
-static int bdrv_qed_check(BlockDriverState *bs, BdrvCheckResult *result,
- BdrvCheckMode fix)
-{
- BDRVQEDState *s = bs->opaque;
-
- return qed_check(s, result, !!fix);
-}
-
-static QEMUOptionParameter qed_create_options[] = {
- {
- .name = BLOCK_OPT_SIZE,
- .type = OPT_SIZE,
- .help = "Virtual disk size (in bytes)"
- }, {
- .name = BLOCK_OPT_BACKING_FILE,
- .type = OPT_STRING,
- .help = "File name of a base image"
- }, {
- .name = BLOCK_OPT_BACKING_FMT,
- .type = OPT_STRING,
- .help = "Image format of the base image"
- }, {
- .name = BLOCK_OPT_CLUSTER_SIZE,
- .type = OPT_SIZE,
- .help = "Cluster size (in bytes)",
- .value = { .n = QED_DEFAULT_CLUSTER_SIZE },
- }, {
- .name = BLOCK_OPT_TABLE_SIZE,
- .type = OPT_SIZE,
- .help = "L1/L2 table size (in clusters)"
- },
- { /* end of list */ }
-};
-
-static BlockDriver bdrv_qed = {
- .format_name = "qed",
- .instance_size = sizeof(BDRVQEDState),
- .create_options = qed_create_options,
-
- .bdrv_probe = bdrv_qed_probe,
- .bdrv_rebind = bdrv_qed_rebind,
- .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_is_allocated = bdrv_qed_co_is_allocated,
- .bdrv_make_empty = bdrv_qed_make_empty,
- .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_change_backing_file = bdrv_qed_change_backing_file,
- .bdrv_invalidate_cache = bdrv_qed_invalidate_cache,
- .bdrv_check = bdrv_qed_check,
-};
-
-static void bdrv_qed_init(void)
-{
- bdrv_register(&bdrv_qed);
-}
-
-block_init(bdrv_qed_init);