From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:57515) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Uc4mF-0006qf-CC for qemu-devel@nongnu.org; Mon, 13 May 2013 22:15:46 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Uc4mC-0000cl-El for qemu-devel@nongnu.org; Mon, 13 May 2013 22:15:43 -0400 Received: from e39.co.us.ibm.com ([32.97.110.160]:46154) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Uc4mC-0000cS-2U for qemu-devel@nongnu.org; Mon, 13 May 2013 22:15:40 -0400 Received: from /spool/local by e39.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 13 May 2013 20:15:38 -0600 Received: from d01relay07.pok.ibm.com (d01relay07.pok.ibm.com [9.56.227.147]) by d01dlp03.pok.ibm.com (Postfix) with ESMTP id E5445C9003E for ; Mon, 13 May 2013 22:15:35 -0400 (EDT) Received: from d01av03.pok.ibm.com (d01av03.pok.ibm.com [9.56.224.217]) by d01relay07.pok.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id r4E2FZEk65011910 for ; Mon, 13 May 2013 22:15:35 -0400 Received: from d01av03.pok.ibm.com (loopback [127.0.0.1]) by d01av03.pok.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id r4E2FZtl030064 for ; Mon, 13 May 2013 23:15:35 -0300 Message-ID: <51919E45.8030402@linux.vnet.ibm.com> Date: Tue, 14 May 2013 10:15:33 +0800 From: Dong Xu Wang MIME-Version: 1.0 References: <1365581513-3475-1-git-send-email-wdongxu@linux.vnet.ibm.com> <1365581513-3475-6-git-send-email-wdongxu@linux.vnet.ibm.com> <20130513150510.GF30855@localhost.localdomain> In-Reply-To: <20130513150510.GF30855@localhost.localdomain> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH V18 5/6] add-cow file format core code. List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Jeff Cody Cc: kwolf@redhat.com, wdongxu@cn.ibm.com, qemu-devel@nongnu.org, stefanha@redhat.com On 2013/5/13 23:07, Jeff Cody wrote: > On Wed, Apr 10, 2013 at 04:11:52PM +0800, Dong Xu Wang wrote: >> add-cow file format core code. It use block-cache.c as cache code. >> It lacks of snapshot_blkdev support. >> >> Signed-off-by: Dong Xu Wang >> --- >> v17-v18: >> 1) use error_report, not fprintf. >> 2) remove version field from header. >> 3) header_size is MAX(cluster_size, 4096). >> 4) introduce s->cluster_sectors. >> 5) use BLKDBG_L2_LOAD/UPDATE. >> >> v16->v17: >> 1) Use stringify. >> >> v15->v16: >> 1) Judge if opts is null in add_cow_create function. >> block/Makefile.objs | 1 + >> block/add-cow.c | 741 ++++++++++++++++++++++++++++++++++++++++++++++ >> block/block-cache.c | 4 +- >> block/qcow2.h | 6 +- >> include/block/block_int.h | 2 + >> 5 files changed, 749 insertions(+), 5 deletions(-) >> create mode 100644 block/add-cow.c >> >> diff --git a/block/Makefile.objs b/block/Makefile.objs >> index 4fe81dc..69cbb09 100644 >> --- a/block/Makefile.objs >> +++ b/block/Makefile.objs >> @@ -1,6 +1,7 @@ >> block-obj-y += raw.o cow.o qcow.o vdi.o vmdk.o cloop.o dmg.o bochs.o vpc.o vvfat.o >> block-obj-y += qcow2.o qcow2-refcount.o qcow2-cluster.o qcow2-snapshot.o >> block-obj-y += block-cache.o >> +block-obj-y += add-cow.o >> block-obj-y += qed.o qed-gencb.o qed-l2-cache.o qed-table.o qed-cluster.o >> block-obj-y += qed-check.o >> block-obj-y += parallels.o blkdebug.o blkverify.o >> diff --git a/block/add-cow.c b/block/add-cow.c >> new file mode 100644 >> index 0000000..904b008 >> --- /dev/null >> +++ b/block/add-cow.c >> @@ -0,0 +1,741 @@ >> +/* >> + * QEMU ADD-COW Disk Format >> + * >> + * Copyright IBM, Corp. 2012 >> + * >> + * Authors: >> + * Dong Xu Wang >> + * >> + * 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-common.h" >> +#include "block/block_int.h" >> +#include "qemu/module.h" >> +#include "block/block-cache.h" >> + >> +#define ACOW_CLUSTER_SIZE 65536 >> +enum { >> + /* compat_features bit */ >> + ACOW_F_ALL_ALLOCATED = 0X01, >> + >> + /* none feature bit used now */ >> + ACOW_FEATURE_MASK = 0, >> + >> + ACOW_MAGIC = 'A' | 'C' << 8 | 'O' << 16 | 'W' << 24, >> + ACOW_CACHE_SIZE = 16, >> + DEFAULT_HEADER_SIZE = 4096, >> + MIN_CLUSTER_BITS = 9, >> + MAX_CLUSTER_BITS = 21, >> +}; >> + >> +typedef struct AddCowHeader { >> + uint32_t magic; >> + >> + uint32_t backing_offset; >> + uint32_t backing_size; >> + uint32_t image_offset; >> + uint32_t image_size; >> + >> + uint32_t cluster_bits; >> + uint64_t features; >> + uint64_t compat_features; >> + uint32_t header_size; >> + >> + char backing_fmt[16]; >> + char image_fmt[16]; >> +} QEMU_PACKED AddCowHeader; >> + >> +typedef struct BDRVAddCowState { >> + BlockDriverState *image_hd; >> + CoMutex lock; >> + int cluster_size; >> + int cluster_sectors; >> + BlockCache *bitmap_cache; >> + uint64_t bitmap_size; >> + AddCowHeader header; >> + char backing_fmt[16]; >> + char image_fmt[16]; >> +} BDRVAddCowState; >> + >> +/* Convert sector_num to offset in bitmap */ >> +static inline int64_t offset_in_bitmap(int64_t sector_num, >> + int64_t cluster_sectors) >> +{ >> + int64_t cluster_num = sector_num / cluster_sectors; >> + return cluster_num / 8; >> +} >> + >> +static inline bool is_cluster_head(int64_t sector_num, >> + int64_t cluster_sectors) >> +{ >> + return sector_num % cluster_sectors == 0; >> +} >> + >> +static inline bool is_cluster_tail(int64_t sector_num, >> + int64_t cluster_sectors) >> +{ >> + return (sector_num + 1) % cluster_sectors == 0; >> +} >> + >> +static void add_cow_header_le_to_cpu(const AddCowHeader *le, AddCowHeader *cpu) >> +{ >> + cpu->magic = le32_to_cpu(le->magic); >> + >> + cpu->backing_offset = le32_to_cpu(le->backing_offset); >> + cpu->backing_size = le32_to_cpu(le->backing_size); >> + cpu->image_offset = le32_to_cpu(le->image_offset); >> + cpu->image_size = le32_to_cpu(le->image_size); >> + >> + cpu->cluster_bits = le32_to_cpu(le->cluster_bits); >> + cpu->features = le64_to_cpu(le->features); >> + cpu->compat_features = le64_to_cpu(le->compat_features); >> + cpu->header_size = le32_to_cpu(le->header_size); >> + >> + memcpy(cpu->backing_fmt, le->backing_fmt, sizeof(cpu->backing_fmt)); >> + memcpy(cpu->image_fmt, le->image_fmt, sizeof(cpu->image_fmt)); >> +} >> + >> +static void add_cow_header_cpu_to_le(const AddCowHeader *cpu, AddCowHeader *le) >> +{ >> + le->magic = cpu_to_le32(cpu->magic); >> + >> + le->backing_offset = cpu_to_le32(cpu->backing_offset); >> + le->backing_size = cpu_to_le32(cpu->backing_size); >> + le->image_offset = cpu_to_le32(cpu->image_offset); >> + le->image_size = cpu_to_le32(cpu->image_size); >> + >> + le->cluster_bits = cpu_to_le32(cpu->cluster_bits); >> + le->features = cpu_to_le64(cpu->features); >> + le->compat_features = cpu_to_le64(cpu->compat_features); >> + le->header_size = cpu_to_le32(cpu->header_size); >> + memcpy(le->backing_fmt, cpu->backing_fmt, sizeof(le->backing_fmt)); >> + memcpy(le->image_fmt, cpu->image_fmt, sizeof(le->image_fmt)); >> +} >> + >> +static int add_cow_probe(const uint8_t *buf, int buf_size, const char *filename) >> +{ >> + const AddCowHeader *header = (const AddCowHeader *)buf; >> + >> + if (buf_size < sizeof(*header)) { >> + return 0; >> + } >> + if (le32_to_cpu(header->magic) == ACOW_MAGIC) { >> + return 100; >> + } >> + return 0; >> +} >> + >> +static int add_cow_create(const char *filename, QemuOpts *opts) >> +{ >> + AddCowHeader header = { >> + .magic = ACOW_MAGIC, >> + .features = 0, >> + .compat_features = 0, >> + }; >> + AddCowHeader le_header; >> + int64_t image_len = 0; >> + const char *backing_filename = NULL, *backing_fmt = NULL; >> + const char *image_filename = NULL, *image_format = NULL; >> + size_t cluster_size = ACOW_CLUSTER_SIZE; >> + BlockDriverState *bs, *backing_bs; >> + BlockDriver *drv = bdrv_find_format("add-cow"); >> + int ret; >> + >> + image_len = qemu_opt_get_size(opts, BLOCK_OPT_SIZE, 0); >> + backing_filename = qemu_opt_get(opts, BLOCK_OPT_BACKING_FILE); >> + backing_fmt = qemu_opt_get(opts, BLOCK_OPT_BACKING_FMT); >> + image_filename = qemu_opt_get(opts, BLOCK_OPT_IMAGE_FILE); >> + image_format = qemu_opt_get(opts, BLOCK_OPT_IMAGE_FMT); >> + cluster_size = qemu_opt_get_size(opts, BLOCK_OPT_CLUSTER_SIZE, >> + ACOW_CLUSTER_SIZE); >> + >> + header.cluster_bits = ffs(cluster_size) - 1; >> + if (header.cluster_bits < MIN_CLUSTER_BITS || >> + header.cluster_bits > MAX_CLUSTER_BITS || >> + (1 << header.cluster_bits) != cluster_size) { >> + error_report( >> + "Cluster size must be a power of two between %d and %dk", >> + 1 << MIN_CLUSTER_BITS, 1 << (MAX_CLUSTER_BITS - 10)); >> + return -EINVAL; >> + } >> + >> + header.header_size = MAX(cluster_size, DEFAULT_HEADER_SIZE); >> + if (backing_filename) { >> + header.backing_offset = sizeof(header); >> + header.backing_size = strlen(backing_filename); >> + >> + if (!backing_fmt) { >> + backing_bs = bdrv_new("image"); >> + ret = bdrv_open(backing_bs, backing_filename, NULL, >> + BDRV_O_RDWR | BDRV_O_CACHE_WB, NULL); >> + if (ret < 0) { >> + return ret; >> + } >> + backing_fmt = bdrv_get_format_name(backing_bs); >> + bdrv_delete(backing_bs); >> + } >> + } else { >> + header.compat_features |= ACOW_F_ALL_ALLOCATED; >> + } >> + >> + if (image_filename) { >> + header.image_offset = sizeof(header) + header.backing_size; >> + header.image_size = strlen(image_filename); >> + } else { >> + error_report("Error: image_file should be given."); >> + return -EINVAL; >> + } >> + >> + if (backing_filename && !strcmp(backing_filename, image_filename)) { >> + error_report("Error: Trying to create an image with the " >> + "same backing file name as the image file name"); >> + return -EINVAL; >> + } >> + >> + if (!strcmp(filename, image_filename)) { >> + error_report("Error: Trying to create an image with the " >> + "same filename as the image file name"); >> + return -EINVAL; >> + } >> + >> + if (header.image_offset + header.image_size > header.header_size) { >> + error_report("image_file name or backing_file name too long."); >> + return -ENOSPC; >> + } >> + >> + ret = bdrv_file_open(&bs, image_filename, NULL, 0); >> + if (ret < 0) { >> + return ret; >> + } >> + bdrv_close(bs); >> + >> + ret = bdrv_create_file(filename, NULL); >> + if (ret < 0) { >> + return ret; >> + } >> + >> + ret = bdrv_file_open(&bs, filename, NULL, BDRV_O_RDWR); >> + if (ret < 0) { >> + return ret; >> + } >> + snprintf(header.backing_fmt, sizeof(header.backing_fmt), "%s", >> + backing_fmt ? backing_fmt : ""); >> + snprintf(header.image_fmt, sizeof(header.image_fmt), "%s", >> + image_format ? image_format : "raw"); >> + add_cow_header_cpu_to_le(&header, &le_header); >> + ret = bdrv_pwrite(bs, 0, &le_header, sizeof(le_header)); >> + if (ret < 0) { >> + bdrv_delete(bs); >> + return ret; >> + } >> + >> + ret = bdrv_pwrite(bs, header.image_offset, image_filename, >> + header.image_size); >> + if (ret < 0) { >> + bdrv_delete(bs); >> + return ret; >> + } >> + >> + if (backing_filename) { >> + ret = bdrv_pwrite(bs, header.backing_offset, backing_filename, >> + header.backing_size); >> + if (ret < 0) { >> + bdrv_delete(bs); >> + return ret; >> + } >> + } >> + bdrv_close(bs); >> + >> + ret = bdrv_open(bs, filename, NULL, BDRV_O_RDWR | BDRV_O_NO_FLUSH, drv); >> + if (ret < 0) { >> + bdrv_delete(bs); >> + return ret; >> + } >> + >> + ret = bdrv_truncate(bs, image_len); >> + bdrv_delete(bs); >> + return ret; >> +} >> + >> +static int add_cow_open(BlockDriverState *bs, QDict *options, int flags) >> +{ >> + char image_filename[PATH_MAX]; >> + char tmp_name[PATH_MAX]; >> + int ret; >> + int sector_per_byte; >> + BDRVAddCowState *s = bs->opaque; >> + AddCowHeader le_header; >> + char backing_filename[PATH_MAX]; >> + >> + ret = bdrv_pread(bs->file, 0, &le_header, sizeof(le_header)); >> + if (ret < 0) { >> + goto fail; >> + } >> + >> + add_cow_header_le_to_cpu(&le_header, &s->header); >> + >> + if (s->header.magic != ACOW_MAGIC) { >> + ret = -EINVAL; >> + goto fail; >> + } >> + >> + if (s->header.features & ~ACOW_FEATURE_MASK) { >> + char buf[64]; >> + snprintf(buf, sizeof(buf), "Feature Flags: %" PRIx64, >> + s->header.features & ~ACOW_FEATURE_MASK); >> + qerror_report(QERR_UNKNOWN_BLOCK_FORMAT_FEATURE, >> + bs->device_name, "add-cow", buf); >> + return -ENOTSUP; >> + } >> + >> + if ((s->header.compat_features & ACOW_F_ALL_ALLOCATED) == 0) { >> + snprintf(bs->backing_format, sizeof(bs->backing_format), >> + "%s", s->header.backing_fmt); >> + } >> + >> + if (s->header.cluster_bits < MIN_CLUSTER_BITS || >> + s->header.cluster_bits > MAX_CLUSTER_BITS) { >> + ret = -EINVAL; >> + goto fail; >> + } >> + >> + s->cluster_size = 1 << s->header.cluster_bits; >> + if (s->header.header_size != MAX(s->cluster_size, DEFAULT_HEADER_SIZE)) { >> + char buf[64]; >> + snprintf(buf, sizeof(buf), "Header size: %d", >> + s->header.header_size); >> + qerror_report(QERR_UNKNOWN_BLOCK_FORMAT_FEATURE, >> + bs->device_name, "add-cow", buf); >> + return -ENOTSUP; >> + } >> + >> + if ((s->header.compat_features & ACOW_F_ALL_ALLOCATED) == 0) { >> + ret = bdrv_read_string(bs->file, s->header.backing_offset, >> + s->header.backing_size, >> + bs->backing_file, >> + sizeof(bs->backing_file)); >> + if (ret < 0) { >> + goto fail; >> + } >> + } >> + >> + ret = bdrv_read_string(bs->file, s->header.image_offset, >> + s->header.image_size, tmp_name, >> + sizeof(tmp_name)); >> + if (ret < 0) { >> + goto fail; >> + } >> + >> + if (path_has_protocol(tmp_name)) { >> + pstrcpy(image_filename, sizeof(image_filename), tmp_name); >> + } else { >> + path_combine(image_filename, sizeof(image_filename), >> + bs->filename, tmp_name); >> + } >> + bdrv_get_full_backing_filename(bs, backing_filename, >> + sizeof(backing_filename)); >> + if (!strcmp(backing_filename, image_filename)) { >> + error_report("Error: backing file and image file are same: %s\n", >> + backing_filename); >> + ret = EINVAL; >> + goto fail; >> + } >> + s->image_hd = bdrv_new(""); >> + ret = bdrv_open(s->image_hd, image_filename, NULL, flags, >> + bdrv_find_format(s->header.image_fmt)); >> + if (ret < 0) { >> + bdrv_delete(s->image_hd); >> + goto fail; >> + } >> + >> + bs->total_sectors = bdrv_getlength(s->image_hd) / BDRV_SECTOR_SIZE; >> + s->cluster_sectors = s->cluster_size / BDRV_SECTOR_SIZE; >> + sector_per_byte = s->cluster_sectors * 8; >> + s->bitmap_size = >> + (bs->total_sectors + sector_per_byte - 1) / sector_per_byte; >> + s->bitmap_cache = block_cache_create(bs, ACOW_CACHE_SIZE, >> + s->cluster_size, >> + BLOCK_TABLE_BITMAP); >> + qemu_co_mutex_init(&s->lock); >> + return 0; >> +fail: >> + return ret; >> +} >> + >> +static void add_cow_close(BlockDriverState *bs) >> +{ >> + BDRVAddCowState *s = bs->opaque; >> + if (s->bitmap_cache) { >> + block_cache_destroy(bs, s->bitmap_cache); >> + } >> + bdrv_delete(s->image_hd); >> +} >> + >> +static bool is_allocated(BlockDriverState *bs, int64_t sector_num) >> +{ >> + BDRVAddCowState *s = bs->opaque; >> + int64_t cluster_num = sector_num / s->cluster_sectors; >> + uint8_t *table = NULL; >> + bool val = false; >> + int ret; >> + >> + uint64_t offset = s->header.header_size + >> + (offset_in_bitmap(sector_num, s->cluster_sectors) >> + & (~(s->cluster_size - 1))); >> + ret = block_cache_get(bs, s->bitmap_cache, offset, (void **)&table); >> + if (ret < 0) { >> + return ret; >> + } >> + >> + val = table[cluster_num / 8 % s->cluster_size] & (1 << (cluster_num % 8)); >> + ret = block_cache_put(bs, s->bitmap_cache, (void **)&table); >> + if (ret < 0) { >> + return ret; >> + } >> + return val; >> +} >> + >> +static coroutine_fn int add_cow_is_allocated(BlockDriverState *bs, >> + int64_t sector_num, int nb_sectors, int *num_same) >> +{ >> + BDRVAddCowState *s = bs->opaque; >> + int changed; >> + >> + if (nb_sectors == 0) { >> + *num_same = 0; >> + return 0; >> + } >> + >> + if (s->header.compat_features & ACOW_F_ALL_ALLOCATED) { >> + *num_same = nb_sectors; >> + return 1; >> + } >> + changed = is_allocated(bs, sector_num); >> + >> + for (*num_same = 1; *num_same < nb_sectors; (*num_same)++) { >> + if (is_allocated(bs, sector_num + *num_same) != changed) { >> + break; >> + } >> + } >> + return changed; >> +} >> + >> +static int add_cow_backing_read(BlockDriverState *bs, QEMUIOVector *qiov, >> + int64_t sector_num, int nb_sectors) >> +{ >> + int n1; >> + if ((sector_num + nb_sectors) <= bs->total_sectors) { >> + return nb_sectors; >> + } >> + if (sector_num >= bs->total_sectors) { >> + n1 = 0; >> + } else { >> + n1 = bs->total_sectors - sector_num; >> + } >> + >> + qemu_iovec_memset(qiov, BDRV_SECTOR_SIZE * n1, >> + 0, BDRV_SECTOR_SIZE * (nb_sectors - n1)); >> + >> + return n1; >> +} >> + >> +static coroutine_fn int add_cow_co_readv(BlockDriverState *bs, >> + int64_t sector_num, >> + int remaining_sectors, >> + QEMUIOVector *qiov) >> +{ >> + BDRVAddCowState *s = bs->opaque; >> + int cur_nr_sectors; >> + uint64_t bytes_done = 0; >> + QEMUIOVector hd_qiov; >> + int n1, ret = 0; >> + >> + qemu_iovec_init(&hd_qiov, qiov->niov); >> + qemu_co_mutex_lock(&s->lock); >> + while (remaining_sectors != 0) { >> + cur_nr_sectors = remaining_sectors; >> + if (add_cow_is_allocated(bs, sector_num, cur_nr_sectors, >> + &cur_nr_sectors)) { >> + qemu_iovec_reset(&hd_qiov); >> + qemu_iovec_concat(&hd_qiov, qiov, bytes_done, >> + cur_nr_sectors * BDRV_SECTOR_SIZE); >> + qemu_co_mutex_unlock(&s->lock); >> + ret = bdrv_co_readv(s->image_hd, sector_num, >> + cur_nr_sectors, &hd_qiov); >> + qemu_co_mutex_lock(&s->lock); >> + if (ret < 0) { >> + goto fail; >> + } >> + } else { >> + if (bs->backing_hd) { >> + qemu_iovec_reset(&hd_qiov); >> + qemu_iovec_concat(&hd_qiov, qiov, bytes_done, >> + cur_nr_sectors * BDRV_SECTOR_SIZE); >> + n1 = add_cow_backing_read(bs->backing_hd, &hd_qiov, >> + sector_num, cur_nr_sectors); >> + if (n1 > 0) { >> + qemu_co_mutex_unlock(&s->lock); >> + ret = bdrv_co_readv(bs->backing_hd, sector_num, >> + cur_nr_sectors, &hd_qiov); >> + qemu_co_mutex_lock(&s->lock); >> + if (ret < 0) { >> + goto fail; >> + } >> + } >> + } else { >> + qemu_iovec_memset(&hd_qiov, 0, 0, >> + BDRV_SECTOR_SIZE * cur_nr_sectors); >> + } >> + } >> + remaining_sectors -= cur_nr_sectors; >> + sector_num += cur_nr_sectors; >> + bytes_done += cur_nr_sectors * BDRV_SECTOR_SIZE; >> + } >> +fail: >> + qemu_co_mutex_unlock(&s->lock); >> + qemu_iovec_destroy(&hd_qiov); >> + return ret; >> +} >> + >> +static int coroutine_fn copy_sectors(BlockDriverState *bs, >> + int n_start, int n_end) >> +{ >> + BDRVAddCowState *s = bs->opaque; >> + QEMUIOVector qiov; >> + struct iovec iov; >> + int n, ret; >> + >> + n = n_end - n_start; >> + if (n <= 0) { >> + return 0; >> + } >> + >> + iov.iov_len = n * BDRV_SECTOR_SIZE; >> + iov.iov_base = qemu_blockalign(bs, iov.iov_len); >> + >> + qemu_iovec_init_external(&qiov, &iov, 1); >> + >> + ret = bdrv_co_readv(bs->backing_hd, n_start, n, &qiov); >> + if (ret < 0) { >> + goto out; >> + } >> + ret = bdrv_co_writev(s->image_hd, n_start, n, &qiov); >> + if (ret < 0) { >> + goto out; >> + } >> + >> + ret = 0; >> +out: >> + qemu_vfree(iov.iov_base); >> + return ret; >> +} >> + >> +static coroutine_fn int add_cow_co_writev(BlockDriverState *bs, >> + int64_t sector_num, >> + int remaining_sectors, >> + QEMUIOVector *qiov) >> +{ >> + BDRVAddCowState *s = bs->opaque; >> + int ret = 0, i; >> + QEMUIOVector hd_qiov; >> + uint8_t *table; >> + uint64_t offset; >> + int mask = s->cluster_sectors - 1; >> + int cluster_mask = s->cluster_size - 1; >> + >> + qemu_co_mutex_lock(&s->lock); >> + qemu_iovec_init(&hd_qiov, qiov->niov); >> + ret = bdrv_co_writev(s->image_hd, sector_num, >> + remaining_sectors, qiov); >> + >> + if (ret < 0) { >> + goto fail; >> + } >> + if ((s->header.compat_features & ACOW_F_ALL_ALLOCATED) == 0) { >> + /* Copy content of unmodified sectors */ >> + if (!is_cluster_head(sector_num, s->cluster_sectors) >> + && !is_allocated(bs, sector_num)) { >> + ret = copy_sectors(bs, sector_num & ~mask, sector_num); >> + if (ret < 0) { >> + goto fail; >> + } >> + } >> + >> + if (!is_cluster_tail(sector_num + remaining_sectors - 1, >> + s->cluster_sectors) >> + && !is_allocated(bs, sector_num + remaining_sectors - 1)) { >> + ret = copy_sectors(bs, sector_num + remaining_sectors, >> + ((sector_num + remaining_sectors) | mask) + 1); >> + if (ret < 0) { >> + goto fail; >> + } >> + } >> + >> + for (i = sector_num / s->cluster_sectors; >> + i <= (sector_num + remaining_sectors - 1) / s->cluster_sectors; >> + i++) { >> + offset = s->header.header_size >> + + (offset_in_bitmap(i * s->cluster_sectors, >> + s->cluster_sectors) & (~cluster_mask)); >> + ret = block_cache_get(bs, s->bitmap_cache, offset, (void **)&table); >> + if (ret < 0) { >> + goto fail; >> + } >> + if ((table[i / 8] & (1 << (i % 8))) == 0) { >> + table[i / 8] |= (1 << (i % 8)); >> + block_cache_entry_mark_dirty(s->bitmap_cache, table); >> + } >> + >> + ret = block_cache_put(bs, s->bitmap_cache, (void **) &table); >> + if (ret < 0) { >> + goto fail; >> + } >> + } >> + } >> + ret = 0; >> +fail: >> + qemu_co_mutex_unlock(&s->lock); >> + qemu_iovec_destroy(&hd_qiov); >> + return ret; >> +} >> + >> +static int bdrv_add_cow_truncate(BlockDriverState *bs, int64_t size) >> +{ >> + BDRVAddCowState *s = bs->opaque; >> + int sector_per_byte = s->cluster_sectors * 8; >> + int ret; >> + int64_t bitmap_size = >> + (size / BDRV_SECTOR_SIZE + sector_per_byte - 1) / sector_per_byte; >> + bitmap_size = (bitmap_size + s->cluster_size - 1) >> + & (~(s->cluster_size - 1)); >> + >> + ret = bdrv_truncate(bs->file, s->header.header_size + bitmap_size); >> + if (ret < 0) { >> + return ret; >> + } >> + >> + ret = bdrv_truncate(s->image_hd, size); >> + if (ret < 0) { >> + return ret; >> + } >> + return 0; >> +} >> + >> +static int add_cow_reopen_prepare(BDRVReopenState *state, >> + BlockReopenQueue *queue, Error **errp) >> +{ >> + BDRVAddCowState *s; >> + int ret = -1; >> + >> + assert(state != NULL); >> + assert(state->bs != NULL); >> + >> + if (queue == NULL) { >> + error_set(errp, ERROR_CLASS_GENERIC_ERROR, >> + "No reopen queue for add-cow"); >> + goto exit; >> + } >> + >> + s = state->bs->opaque; >> + >> + assert(s != NULL); >> + >> + >> + bdrv_reopen_queue(queue, s->image_hd, state->flags); >> + ret = 0; >> + >> +exit: >> + return ret; >> +} >> + >> + >> +static coroutine_fn int add_cow_co_flush(BlockDriverState *bs) >> +{ >> + BDRVAddCowState *s = bs->opaque; >> + int ret; >> + >> + qemu_co_mutex_lock(&s->lock); >> + if (s->bitmap_cache) { >> + ret = block_cache_flush(bs, s->bitmap_cache); >> + if (ret < 0) { >> + return ret; >> + } >> + } >> + ret = bdrv_flush(s->image_hd); >> + qemu_co_mutex_unlock(&s->lock); >> + return ret; >> +} >> + >> +static int add_cow_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) >> +{ >> + BDRVAddCowState *s = bs->opaque; >> + bdi->cluster_size = s->cluster_size; >> + return 0; >> +} >> + >> +static QemuOptsList add_cow_create_opts = { >> + .name = "add-cow-create-opts", >> + .head = QTAILQ_HEAD_INITIALIZER(add_cow_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_IMAGE_FILE, >> + .type = QEMU_OPT_STRING, >> + .help = "File name of a image file" >> + }, >> + { >> + .name = BLOCK_OPT_IMAGE_FMT, >> + .type = QEMU_OPT_STRING, >> + .help = "Image format of the image file" >> + }, >> + { >> + .name = BLOCK_OPT_CLUSTER_SIZE, >> + .type = QEMU_OPT_SIZE, >> + .help = "add-cow cluster size", >> + .def_value_str = stringify(ACOW_CLUSTER_SIZE) > > Hi Dong, > > .def_value_str is undefined - it looks like this series is dependent > on: > > [PATCH V14 1/6] add def_value_str in QemuOptDesc struct and rewrite qemu_opts_print > > In that 6-part series, patches 2,4,5 are also dependent on the above > patch. Should these series be combined? > > You did mention in the header that this uses QemuOpts, but until I > applied and tried compiling, it wasn't obvious (at least to me) the > external patch dependency above. > Ah, yes, I wish QemuOpts patches will be merged first, so add-cow is based on them, so .. > Thanks, > Jeff > > >> + }, >> + { /* end of list */ } >> + } >> +}; >> + >> +static BlockDriver bdrv_add_cow = { >> + .format_name = "add-cow", >> + .instance_size = sizeof(BDRVAddCowState), >> + .bdrv_probe = add_cow_probe, >> + .bdrv_open = add_cow_open, >> + .bdrv_close = add_cow_close, >> + .bdrv_create = add_cow_create, >> + .bdrv_co_readv = add_cow_co_readv, >> + .bdrv_co_writev = add_cow_co_writev, >> + .bdrv_truncate = bdrv_add_cow_truncate, >> + .bdrv_co_is_allocated = add_cow_is_allocated, >> + .bdrv_reopen_prepare = add_cow_reopen_prepare, >> + .bdrv_get_info = add_cow_get_info, >> + >> + .bdrv_create_opts = &add_cow_create_opts, >> + .bdrv_co_flush_to_os = add_cow_co_flush, >> +}; >> + >> +static void bdrv_add_cow_init(void) >> +{ >> + bdrv_register(&bdrv_add_cow); >> +} >> + >> +block_init(bdrv_add_cow_init); >> diff --git a/block/block-cache.c b/block/block-cache.c >> index 3544691..4824632 100644 >> --- a/block/block-cache.c >> +++ b/block/block-cache.c >> @@ -130,7 +130,7 @@ static int block_cache_entry_flush(BlockDriverState *bs, BlockCache *c, int i) >> } else if (c->table_type == BLOCK_TABLE_L2) { >> BLKDBG_EVENT(bs->file, BLKDBG_L2_UPDATE); >> } else if (c->table_type == BLOCK_TABLE_BITMAP) { >> - BLKDBG_EVENT(bs->file, BLKDBG_COW_WRITE); >> + BLKDBG_EVENT(bs->file, BLKDBG_L2_LOAD); >> } >> >> ret = bdrv_pwrite(bs->file, c->entries[i].offset, >> @@ -265,7 +265,7 @@ static int block_cache_do_get(BlockDriverState *bs, BlockCache *c, >> if (c->table_type == BLOCK_TABLE_L2) { >> BLKDBG_EVENT(bs->file, BLKDBG_L2_LOAD); >> } else if (c->table_type == BLOCK_TABLE_BITMAP) { >> - BLKDBG_EVENT(bs->file, BLKDBG_COW_READ); >> + BLKDBG_EVENT(bs->file, BLKDBG_L2_LOAD); >> } >> >> ret = bdrv_pread(bs->file, offset, c->entries[i].table, >> diff --git a/block/qcow2.h b/block/qcow2.h >> index e7f6aec..a4e514b 100644 >> --- a/block/qcow2.h >> +++ b/block/qcow2.h >> @@ -98,6 +98,9 @@ typedef struct QCowSnapshot { >> uint64_t vm_clock_nsec; >> } QCowSnapshot; >> >> +struct BlockCache; >> +typedef struct BlockCache BlockCache; >> + >> typedef struct Qcow2UnknownHeaderExtension { >> uint32_t magic; >> uint32_t len; >> @@ -389,7 +392,4 @@ int qcow2_snapshot_load_tmp(BlockDriverState *bs, const char *snapshot_name); >> void qcow2_free_snapshots(BlockDriverState *bs); >> int qcow2_read_snapshots(BlockDriverState *bs); >> >> -/* qcow2-cache.c functions */ >> - >> - >> #endif >> diff --git a/include/block/block_int.h b/include/block/block_int.h >> index a44a9ac..b9eb9b8 100644 >> --- a/include/block/block_int.h >> +++ b/include/block/block_int.h >> @@ -57,6 +57,8 @@ >> #define BLOCK_OPT_COMPAT_LEVEL "compat" >> #define BLOCK_OPT_LAZY_REFCOUNTS "lazy_refcounts" >> #define BLOCK_OPT_ADAPTER_TYPE "adapter_type" >> +#define BLOCK_OPT_IMAGE_FILE "image_file" >> +#define BLOCK_OPT_IMAGE_FMT "image_fmt" >> >> typedef struct BdrvTrackedRequest BdrvTrackedRequest; >> >> -- >> 1.7.11.7 >> >> > >