From cac8f4a60fc5c372bacd59eeff0646955fb4f246 Mon Sep 17 00:00:00 2001 From: Liu Yuan Date: Tue, 23 Apr 2013 14:03:33 +0800 Subject: [PATCH] sheepdog: add discard/trim support for sheepdog The 'TRIM' command from VM that is to release underlying data storage for better thin-provision is already supported by the Sheepdog. This patch adds the TRIM support at QEMU part. For older Sheepdog that doesn't support it, we return 0(success) to upper layer. Cc: MORITA Kazutaka Cc: Kevin Wolf Cc: Stefan Hajnoczi Cc: Paolo Bonzini Signed-off-by: Liu Yuan Signed-off-by: Stefan Hajnoczi --- block/sheepdog.c | 64 +++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 63 insertions(+), 1 deletion(-) diff --git a/block/sheepdog.c b/block/sheepdog.c index 20b5d06c52..6a72c1ee40 100644 --- a/block/sheepdog.c +++ b/block/sheepdog.c @@ -27,6 +27,8 @@ #define SD_OP_CREATE_AND_WRITE_OBJ 0x01 #define SD_OP_READ_OBJ 0x02 #define SD_OP_WRITE_OBJ 0x03 +/* 0x04 is used internally by Sheepdog */ +#define SD_OP_DISCARD_OBJ 0x05 #define SD_OP_NEW_VDI 0x11 #define SD_OP_LOCK_VDI 0x12 @@ -269,6 +271,7 @@ enum AIOCBState { AIOCB_WRITE_UDATA, AIOCB_READ_UDATA, AIOCB_FLUSH_CACHE, + AIOCB_DISCARD_OBJ, }; struct SheepdogAIOCB { @@ -298,6 +301,7 @@ typedef struct BDRVSheepdogState { char name[SD_MAX_VDI_LEN]; bool is_snapshot; uint32_t cache_flags; + bool discard_supported; char *host_spec; bool is_unix; @@ -656,7 +660,7 @@ static void coroutine_fn aio_read_response(void *opaque) int ret; AIOReq *aio_req = NULL; SheepdogAIOCB *acb; - unsigned long idx; + uint64_t idx; if (QLIST_EMPTY(&s->inflight_aio_head)) { goto out; @@ -727,6 +731,21 @@ static void coroutine_fn aio_read_response(void *opaque) rsp.result = SD_RES_SUCCESS; } break; + case AIOCB_DISCARD_OBJ: + switch (rsp.result) { + case SD_RES_INVALID_PARMS: + error_report("sheep(%s) doesn't support discard command", + s->host_spec); + rsp.result = SD_RES_SUCCESS; + s->discard_supported = false; + break; + case SD_RES_SUCCESS: + idx = data_oid_to_idx(aio_req->oid); + s->inode.data_vdi_id[idx] = 0; + break; + default: + break; + } } if (rsp.result != SD_RES_SUCCESS) { @@ -1016,6 +1035,9 @@ static int coroutine_fn add_aio_request(BDRVSheepdogState *s, AIOReq *aio_req, wlen = datalen; hdr.flags = SD_FLAG_CMD_WRITE | flags; break; + case AIOCB_DISCARD_OBJ: + hdr.opcode = SD_OP_DISCARD_OBJ; + break; } if (s->cache_flags) { @@ -1197,6 +1219,7 @@ static int sd_open(BlockDriverState *bs, QDict *options, int flags) if (flags & BDRV_O_NOCACHE) { s->cache_flags = SD_FLAG_CMD_DIRECT; } + s->discard_supported = true; if (snapid || tag[0] != '\0') { dprintf("%" PRIx32 " snapshot inode was open.\n", vid); @@ -1662,6 +1685,15 @@ static int coroutine_fn sd_co_rw_vector(void *p) flags = SD_FLAG_CMD_COW; } break; + case AIOCB_DISCARD_OBJ: + /* + * We discard the object only when the whole object is + * 1) allocated 2) trimmed. Otherwise, simply skip it. + */ + if (len != SD_DATA_OBJ_SIZE || inode->data_vdi_id[idx] == 0) { + goto done; + } + break; default: break; } @@ -2107,6 +2139,33 @@ static int sd_load_vmstate(BlockDriverState *bs, uint8_t *data, } +static coroutine_fn int sd_co_discard(BlockDriverState *bs, int64_t sector_num, + int nb_sectors) +{ + SheepdogAIOCB *acb; + QEMUIOVector dummy; + BDRVSheepdogState *s = bs->opaque; + int ret; + + if (!s->discard_supported) { + return 0; + } + + acb = sd_aio_setup(bs, &dummy, sector_num, nb_sectors); + acb->aiocb_type = AIOCB_DISCARD_OBJ; + acb->aio_done_func = sd_finish_aiocb; + + ret = sd_co_rw_vector(acb); + if (ret <= 0) { + qemu_aio_release(acb); + return ret; + } + + qemu_coroutine_yield(); + + return acb->ret; +} + static QEMUOptionParameter sd_create_options[] = { { .name = BLOCK_OPT_SIZE, @@ -2139,6 +2198,7 @@ static BlockDriver bdrv_sheepdog = { .bdrv_co_readv = sd_co_readv, .bdrv_co_writev = sd_co_writev, .bdrv_co_flush_to_disk = sd_co_flush_to_disk, + .bdrv_co_discard = sd_co_discard, .bdrv_snapshot_create = sd_snapshot_create, .bdrv_snapshot_goto = sd_snapshot_goto, @@ -2164,6 +2224,7 @@ static BlockDriver bdrv_sheepdog_tcp = { .bdrv_co_readv = sd_co_readv, .bdrv_co_writev = sd_co_writev, .bdrv_co_flush_to_disk = sd_co_flush_to_disk, + .bdrv_co_discard = sd_co_discard, .bdrv_snapshot_create = sd_snapshot_create, .bdrv_snapshot_goto = sd_snapshot_goto, @@ -2189,6 +2250,7 @@ static BlockDriver bdrv_sheepdog_unix = { .bdrv_co_readv = sd_co_readv, .bdrv_co_writev = sd_co_writev, .bdrv_co_flush_to_disk = sd_co_flush_to_disk, + .bdrv_co_discard = sd_co_discard, .bdrv_snapshot_create = sd_snapshot_create, .bdrv_snapshot_goto = sd_snapshot_goto, -- GitLab