What if the old code from qemu connects to the latest sheepdog with basic data structure changed ? Will it destroy our precious data ? Btw: It seems that we don't have version defined for client-server communication. Is that right ? > -----Original Message----- > From: sheepdog-bounces at lists.wpkg.org > [mailto:sheepdog-bounces at lists.wpkg.org] On Behalf Of 无觉 > Sent: Friday, April 20, 2012 3:08 PM > To: yaohaiting.wujue at gmail.com; sheepdog at lists.wpkg.org > Subject: [Sheepdog] 答复: [PATCH v3] sheep: change snapshot/clone flow > > If this patch has been merged, the sheepdog driver in qemu project also need > changed. > > I have prepared the patch as below, but not submit to qemu project. > > Perhaps I should submit the patch to qemu after the confirmation here. > > --- > block/sheepdog.c | 37 ++++++++++++++++++++----------------- > 1 files changed, 20 insertions(+), 17 deletions(-) > > diff --git a/block/sheepdog.c b/block/sheepdog.c > index 3eaf625..cec5294 100644 > --- a/block/sheepdog.c > +++ b/block/sheepdog.c > @@ -167,7 +167,6 @@ typedef struct SheepdogInode { > char name[SD_MAX_VDI_LEN]; > char tag[SD_MAX_VDI_TAG_LEN]; > uint64_t ctime; > - uint64_t snap_ctime; > uint64_t vm_clock_nsec; > uint64_t vdi_size; > uint64_t vm_state_size; > @@ -177,6 +176,9 @@ typedef struct SheepdogInode { > uint32_t snap_id; > uint32_t vdi_id; > uint32_t parent_vdi_id; > + uint32_t snap_vdi_id; > + /* padding is to memory alignment */ > + uint32_t padding; > uint32_t child_vdi_id[MAX_CHILDREN]; > uint32_t data_vdi_id[MAX_DATA_OBJS]; > } SheepdogInode; > @@ -203,7 +205,7 @@ static inline uint64_t fnv_64a_buf(void *buf, size_t len, > uint64_t hval) > > static inline int is_data_obj_writable(SheepdogInode *inode, unsigned int idx) > { > - return inode->vdi_id == inode->data_vdi_id[idx]; > + return inode->snap_vdi_id == inode->data_vdi_id[idx]; > } > > static inline int is_data_obj(uint64_t oid) > @@ -233,7 +235,7 @@ static inline uint64_t vid_to_data_oid(uint32_t vid, > uint32_t idx) > > static inline int is_snapshot(struct SheepdogInode *inode) > { > - return !!inode->snap_ctime; > + return inode->snap_id; > } > > #undef dprintf > @@ -694,14 +696,14 @@ static void coroutine_fn aio_read_response(void > *opaque) > } > idx = data_oid_to_idx(aio_req->oid); > > - if (s->inode.data_vdi_id[idx] != s->inode.vdi_id) { > + if (s->inode.data_vdi_id[idx] != s->inode.snap_vdi_id) { > /* > * If the object is newly created one, we need to update > * the vdi object (metadata object). min_dirty_data_idx > * and max_dirty_data_idx are changed to include updated > * index between them. > */ > - s->inode.data_vdi_id[idx] = s->inode.vdi_id; > + s->inode.data_vdi_id[idx] = s->inode.snap_vdi_id; > s->max_dirty_data_idx = MAX(idx, s->max_dirty_data_idx); > s->min_dirty_data_idx = MIN(idx, s->min_dirty_data_idx); > > @@ -1552,7 +1554,7 @@ static int coroutine_fn sd_co_rw_vector(void *p) > dprintf("update ino (%" PRIu32") %" PRIu64 " %" PRIu64 > " %" PRIu64 "\n", inode->vdi_id, oid, > vid_to_data_oid(inode->data_vdi_id[idx], idx), idx); > - oid = vid_to_data_oid(inode->vdi_id, idx); > + oid = vid_to_data_oid(inode->snap_vdi_id, idx); > dprintf("new oid %lx\n", oid); > } > > @@ -1710,7 +1712,6 @@ static int sd_snapshot_create(BlockDriverState *bs, > QEMUSnapshotInfo *sn_info) > > s->inode.vm_state_size = sn_info->vm_state_size; > s->inode.vm_clock_nsec = sn_info->vm_clock_nsec; > - strncpy(s->inode.tag, sn_info->name, sizeof(s->inode.tag)); > /* we don't need to update entire object */ > datalen = SD_INODE_SIZE - sizeof(s->inode.data_vdi_id); > > @@ -1721,14 +1722,6 @@ static int sd_snapshot_create(BlockDriverState > *bs, QEMUSnapshotInfo *sn_info) > goto cleanup; > } > > - ret = write_object(fd, (char *)&s->inode, vid_to_vdi_oid(s->inode.vdi_id), > - s->inode.nr_copies, datalen, 0, 0, > s->cache_enabled); > - if (ret < 0) { > - error_report("failed to write snapshot's inode."); > - ret = -EIO; > - goto cleanup; > - } > - > ret = do_sd_create(s->name, s->inode.vdi_size, s->inode.vdi_id, > &new_vid, 1, > s->addr, s->port); > if (ret < 0) { > @@ -1750,6 +1743,16 @@ static int sd_snapshot_create(BlockDriverState > *bs, QEMUSnapshotInfo *sn_info) > } > > memcpy(&s->inode, inode, datalen); > + strncpy(s->inode.tag, sn_info->name, sizeof(s->inode.tag)); > + > + ret = write_object(fd, (char *)&s->inode, vid_to_vdi_oid(new_vid), > + s->inode.nr_copies, datalen, 0, 0, s->cache_enabled); > + if (ret < 0) { > + error_report("failed to write snapshot's inode."); > + ret = -EIO; > + goto cleanup; > + } > + > dprintf("s->inode: name %s snap_id %x oid %x\n", > s->inode.name, s->inode.snap_id, s->inode.vdi_id); > > @@ -1899,8 +1902,8 @@ static int sd_snapshot_list(BlockDriverState *bs, > QEMUSnapshotInfo **psn_tab) > } > > if (!strcmp(inode.name, s->name) && is_snapshot(&inode)) { > - sn_tab[found].date_sec = inode.snap_ctime >> 32; > - sn_tab[found].date_nsec = inode.snap_ctime & 0xffffffff; > + sn_tab[found].date_sec = inode.ctime >> 32; > + sn_tab[found].date_nsec = inode.ctime & 0xffffffff; > sn_tab[found].vm_state_size = inode.vm_state_size; > sn_tab[found].vm_clock_nsec = inode.vm_clock_nsec; > > Thanks > Haiting > > -----邮件原件----- > 发件人: yaohaiting.wujue at gmail.com [mailto:yaohaiting.wujue at gmail.com] > 发送时间: 2012年4月20日 14:40 > 收件人: sheepdog at lists.wpkg.org > 抄送: 无觉 > 主题: [PATCH v3] sheep: change snapshot/clone flow > > From: HaiTing Yao <wujue.yht at taobao.com> > > When create snapshot for source VDI, the new created VDI used as source > VDI, and the old source VDI used as snapshot. This flow make users > confused about VDI and snapshot relation. The snapshot metadata maybe is > stored on multi-VDI, so need read multi VDIs inode to get snapshot list. > > When create snapshot, we does not need change new created VDI to source > VDI. The source VDI just need use snapshot VDI ID as its object data ID. > > Show one example. > > Before modification: > > Name Id Size Used Shared Creation time VDI id > Tag > s v1 1 64 MB 20 MB 0.0 MB 2012-03-26 16:55 709128 > s v1 2 64 MB 0.0 MB 20 MB 2012-03-26 16:56 709129 > sn3 > v1 3 64 MB 0.0 MB 20 MB 2012-03-26 16:56 70912a > > After modification: > > Name Id Size Used Shared Creation time VDI id > Tag > v1 0 64 MB 20 MB 0.0 MB 2012-03-27 11:06 709128 > s v1 1 64 MB 0.0 MB 20 MB 2012-03-27 11:06 709129 > s v1 2 64 MB 0.0 MB 20 MB 2012-03-27 11:07 70912a > sn3 > > Signed-off-by: HaiTing Yao <wujue.yht at taobao.com> > --- > collie/common.c | 2 +- > collie/vdi.c | 33 ++++++++++++++++++++++----------- > include/sheepdog_proto.h | 6 ++++-- > sheep/vdi.c | 18 ++++++++++-------- > 4 files changed, 37 insertions(+), 22 deletions(-) > > changes from v2: > > 1, Tag display has been merged, so I removed the display from my patch > 2, Add padding to inode structure, not used packed attribute any more > > diff --git a/collie/common.c b/collie/common.c > index f4301c4..636b821 100644 > --- a/collie/common.c > +++ b/collie/common.c > @@ -13,7 +13,7 @@ > > int is_current(struct sheepdog_inode *i) > { > - return !i->snap_ctime; > + return !i->snap_id; > } > > char *size_to_str(uint64_t _size, char *str, int str_size) > diff --git a/collie/vdi.c b/collie/vdi.c > index 352e10c..0962fc2 100644 > --- a/collie/vdi.c > +++ b/collie/vdi.c > @@ -93,7 +93,10 @@ static void print_vdi_list(uint32_t vid, char *name, char > *tag, uint32_t snapid, > for (idx = 0; idx < MAX_DATA_OBJS; idx++) { > if (!i->data_vdi_id[idx]) > continue; > - if (is_data_obj_writeable(i, idx)) > + if (!i->parent_vdi_id) > + my_objs++; > + /* for clone VDI */ > + else if ((!i->snap_id) && is_data_obj_writeable(i, idx)) > my_objs++; > else > cow_objs++; > @@ -522,7 +525,7 @@ out: > static int vdi_snapshot(int argc, char **argv) > { > char *vdiname = argv[optind++]; > - uint32_t vid; > + uint32_t vid, own_vid; > int ret; > char buf[SD_INODE_HEADER_SIZE]; > struct sheepdog_inode *inode = (struct sheepdog_inode *)buf; > @@ -539,20 +542,26 @@ static int vdi_snapshot(int argc, char **argv) > return EXIT_FAILURE; > } > > - ret = sd_read_object(vid_to_vdi_oid(vid), inode, > SD_INODE_HEADER_SIZE, 0); > - if (ret != SD_RES_SUCCESS) { > - fprintf(stderr, "Failed to read an inode header\n"); > + ret = do_vdi_create(vdiname, inode->vdi_size, vid, &own_vid, 1); > + > + if (ret < 0) { > + fprintf(stderr, "Failed to write VDI %s\n", vdiname); > return EXIT_FAILURE; > } > > if (vdi_cmd_data.snapshot_tag[0]) { > - ret = sd_write_object(vid_to_vdi_oid(vid), 0, > vdi_cmd_data.snapshot_tag, > + ret = sd_read_object(vid_to_vdi_oid(own_vid), inode, > SD_INODE_HEADER_SIZE, 0); > + if (ret != SD_RES_SUCCESS) { > + fprintf(stderr, "Failed to read an inode > header\n"); > + return EXIT_FAILURE; > + } > + ret = sd_write_object(vid_to_vdi_oid(own_vid), 0, > vdi_cmd_data.snapshot_tag, > SD_MAX_VDI_TAG_LEN, > offsetof(struct sheepdog_inode, > tag), > 0, inode->nr_copies, 0); > } > > - return do_vdi_create(vdiname, inode->vdi_size, vid, NULL, 1); > + return ret; > } > > static int vdi_clone(int argc, char **argv) > @@ -1140,6 +1149,7 @@ static int vdi_read(int argc, char **argv) > goto out; > } > > + > if (inode->vdi_size < offset) { > fprintf(stderr, "Read offset is beyond the end of the > VDI\n"); > ret = EXIT_FAILURE; > @@ -1284,7 +1294,7 @@ static int vdi_write(int argc, char **argv) > remain -= ret; > } > > - inode->data_vdi_id[idx] = inode->vdi_id; > + inode->data_vdi_id[idx] = inode->snap_vdi_id; > oid = vid_to_data_oid(inode->data_vdi_id[idx], idx); > ret = sd_write_object(oid, old_oid, buf, len, offset, flags, > inode->nr_copies, create); > @@ -1295,9 +1305,10 @@ static int vdi_write(int argc, char **argv) > } > > if (create) { > - ret = sd_write_object(vid_to_vdi_oid(vid), 0, &vid, > sizeof(vid), > - > SD_INODE_HEADER_SIZE + sizeof(vid) * idx, 0, > - inode->nr_copies, 0); > + /* snap_vdi_id is equal to vdi_id when no > snapshot */ > + ret = sd_write_object(vid_to_vdi_oid(vid), 0, > &inode->snap_vdi_id, > + sizeof(inode->snap_vdi_id), > SD_INODE_HEADER_SIZE + sizeof(vid) * idx, > + 0, inode->nr_copies, 0); > if (ret) { > ret = EXIT_FAILURE; > goto out; > diff --git a/include/sheepdog_proto.h b/include/sheepdog_proto.h > index 11c2c7c..8691901 100644 > --- a/include/sheepdog_proto.h > +++ b/include/sheepdog_proto.h > @@ -179,7 +179,6 @@ struct sheepdog_inode { > char name[SD_MAX_VDI_LEN]; > char tag[SD_MAX_VDI_TAG_LEN]; > uint64_t ctime; > - uint64_t snap_ctime; > uint64_t vm_clock_nsec; > uint64_t vdi_size; > uint64_t vm_state_size; > @@ -189,6 +188,9 @@ struct sheepdog_inode { > uint32_t snap_id; > uint32_t vdi_id; > uint32_t parent_vdi_id; > + uint32_t snap_vdi_id; > + /* padding is to memory alignment */ > + uint32_t padding; > uint32_t child_vdi_id[MAX_CHILDREN]; > uint32_t data_vdi_id[MAX_DATA_OBJS]; > }; > @@ -240,7 +242,7 @@ static inline uint64_t hash_64(uint64_t val, unsigned > int bits) > > static inline int is_data_obj_writeable(struct sheepdog_inode *inode, int idx) > { > - return inode->vdi_id == inode->data_vdi_id[idx]; > + return inode->snap_vdi_id == inode->data_vdi_id[idx]; > } > > static inline int is_vdi_obj(uint64_t oid) > diff --git a/sheep/vdi.c b/sheep/vdi.c > index 71912ba..81f1a66 100644 > --- a/sheep/vdi.c > +++ b/sheep/vdi.c > @@ -82,10 +82,10 @@ static int create_vdi_obj(uint32_t epoch, char *name, > uint32_t new_vid, uint64_t > ret = SD_RES_BASE_VDI_READ; > goto out; > } > - > - cur->snap_ctime = (uint64_t) tv.tv_sec << 32 | > tv.tv_usec * 1000; > - } else > - base->snap_ctime = (uint64_t) tv.tv_sec << 32 | > tv.tv_usec * 1000; > + } else { > + base->snap_vdi_id = new_vid; > + size = base->vdi_size; > + } > } > > strncpy(new->name, name, sizeof(new->name)); > @@ -96,6 +96,7 @@ static int create_vdi_obj(uint32_t epoch, char *name, > uint32_t new_vid, uint64_t > new->nr_copies = copies; > new->block_size_shift = find_next_bit(&block_size, BITS_PER_LONG, > 0); > new->snap_id = snapid; > + new->snap_vdi_id = new_vid; > > if (base_vid) { > int i; > @@ -192,14 +193,15 @@ static int find_first_vdi(uint32_t epoch, unsigned > long start, unsigned long end > } > > if (!strncmp(inode->name, name, strlen(inode->name))) { > + if (!*next_snap) > + *next_snap = inode->snap_id + 1; > vdi_found = 1; > if (tag && tag[0] && > strncmp(inode->tag, tag, > sizeof(inode->tag)) != 0) > continue; > - if (snapid && snapid != inode->snap_id) > + if (snapid != inode->snap_id) > continue; > > - *next_snap = inode->snap_id + 1; > *vid = inode->vdi_id; > *nr_copies = inode->nr_copies; > if (ctime) > @@ -280,7 +282,7 @@ int add_vdi(uint32_t epoch, char *data, int data_len, > uint64_t size, > int is_snapshot, unsigned int *nr_copies) > { > uint32_t cur_vid = 0; > - uint32_t next_snapid; > + uint32_t next_snapid = 0; > unsigned long nr, deleted_nr = SD_NR_VDIS, right_nr = SD_NR_VDIS; > int ret; > char *name; > @@ -313,7 +315,7 @@ int add_vdi(uint32_t epoch, char *data, int data_len, > uint64_t size, > else > nr = deleted_nr; /* we can recycle a deleted VDI > */ > > - next_snapid = 1; > + next_snapid = 0; > } > > *new_vid = nr; > -- > 1.7.1 > > > ________________________________ > > This email (including any attachments) is confidential and may be legally > privileged. If you received this email in error, please delete it immediately and > do not copy it or use it for any purpose or disclose its contents to any other > person. Thank you. > > 本电邮(包括任何附件)可能含有机密资料并受法律保护。如您不是正确的收 > 件人，请您立即删除本邮件。请不要将本电邮进行复制并用作任何其他用 > 途、或透露本邮件之内容。谢谢。 > -- > sheepdog mailing list > sheepdog at lists.wpkg.org > http://lists.wpkg.org/mailman/listinfo/sheepdog |