diff options
| -rw-r--r-- | block/io.c | 47 | ||||
| -rw-r--r-- | block/qcow2-cluster.c | 2 | ||||
| -rw-r--r-- | include/block/block.h | 17 | ||||
| -rw-r--r-- | qemu-img.c | 25 |
4 files changed, 58 insertions, 33 deletions
diff --git a/block/io.c b/block/io.c index ad84d84888..890d3c073b 100644 --- a/block/io.c +++ b/block/io.c @@ -716,9 +716,9 @@ int bdrv_pwrite_zeroes(BdrvChild *child, int64_t offset, */ int bdrv_make_zero(BdrvChild *child, BdrvRequestFlags flags) { - int64_t target_size, ret, bytes, offset = 0; + int ret; + int64_t target_size, bytes, offset = 0; BlockDriverState *bs = child->bs; - int n; /* sectors */ target_size = bdrv_getlength(bs); if (target_size < 0) { @@ -730,24 +730,23 @@ int bdrv_make_zero(BdrvChild *child, BdrvRequestFlags flags) if (bytes <= 0) { return 0; } - ret = bdrv_get_block_status(bs, offset >> BDRV_SECTOR_BITS, - bytes >> BDRV_SECTOR_BITS, &n, NULL); + ret = bdrv_block_status(bs, offset, bytes, &bytes, NULL, NULL); if (ret < 0) { error_report("error getting block status at offset %" PRId64 ": %s", offset, strerror(-ret)); return ret; } if (ret & BDRV_BLOCK_ZERO) { - offset += n * BDRV_SECTOR_BITS; + offset += bytes; continue; } - ret = bdrv_pwrite_zeroes(child, offset, n * BDRV_SECTOR_SIZE, flags); + ret = bdrv_pwrite_zeroes(child, offset, bytes, flags); if (ret < 0) { error_report("error writing zeroes at offset %" PRId64 ": %s", offset, strerror(-ret)); return ret; } - offset += n * BDRV_SECTOR_SIZE; + offset += bytes; } } @@ -2045,13 +2044,35 @@ int64_t bdrv_get_block_status_above(BlockDriverState *bs, nb_sectors, pnum, file); } -int64_t bdrv_get_block_status(BlockDriverState *bs, - int64_t sector_num, - int nb_sectors, int *pnum, - BlockDriverState **file) +int bdrv_block_status(BlockDriverState *bs, int64_t offset, int64_t bytes, + int64_t *pnum, int64_t *map, BlockDriverState **file) { - return bdrv_get_block_status_above(bs, backing_bs(bs), - sector_num, nb_sectors, pnum, file); + int64_t ret; + int n; + + assert(QEMU_IS_ALIGNED(offset | bytes, BDRV_SECTOR_SIZE)); + assert(pnum); + /* + * The contract allows us to return pnum smaller than bytes, even + * if the next query would see the same status; we truncate the + * request to avoid overflowing the driver's 32-bit interface. + */ + bytes = MIN(bytes, BDRV_REQUEST_MAX_BYTES); + ret = bdrv_get_block_status_above(bs, backing_bs(bs), + offset >> BDRV_SECTOR_BITS, + bytes >> BDRV_SECTOR_BITS, &n, file); + if (ret < 0) { + assert(INT_MIN <= ret); + *pnum = 0; + return ret; + } + *pnum = n * BDRV_SECTOR_SIZE; + if (map) { + *map = ret & BDRV_BLOCK_OFFSET_MASK; + } else { + ret &= ~BDRV_BLOCK_OFFSET_VALID; + } + return ret & ~BDRV_BLOCK_OFFSET_MASK; } int coroutine_fn bdrv_is_allocated(BlockDriverState *bs, int64_t offset, diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c index 0e5aec81cb..fb10e26068 100644 --- a/block/qcow2-cluster.c +++ b/block/qcow2-cluster.c @@ -1632,7 +1632,7 @@ static int discard_single_l2(BlockDriverState *bs, uint64_t offset, * cluster is already marked as zero, or if it's unallocated and we * don't have a backing file. * - * TODO We might want to use bdrv_get_block_status(bs) here, but we're + * TODO We might want to use bdrv_block_status(bs) here, but we're * holding s->lock, so that doesn't work today. * * If full_discard is true, the sector should not read back as zeroes, diff --git a/include/block/block.h b/include/block/block.h index 440f3e9e39..7ac851f82f 100644 --- a/include/block/block.h +++ b/include/block/block.h @@ -121,7 +121,7 @@ typedef struct HDGeometry { #define BDRV_REQUEST_MAX_BYTES (BDRV_REQUEST_MAX_SECTORS << BDRV_SECTOR_BITS) /* - * Allocation status flags for bdrv_get_block_status() and friends. + * Allocation status flags for bdrv_block_status() and friends. * * Public flags: * BDRV_BLOCK_DATA: allocation for data at offset is tied to this layer @@ -136,10 +136,11 @@ typedef struct HDGeometry { * that the block layer recompute the answer from the returned * BDS; must be accompanied by just BDRV_BLOCK_OFFSET_VALID. * - * If BDRV_BLOCK_OFFSET_VALID is set, bits 9-62 (BDRV_BLOCK_OFFSET_MASK) - * represent the offset in the returned BDS that is allocated for the - * corresponding raw data; however, whether that offset actually contains - * data also depends on BDRV_BLOCK_DATA and BDRV_BLOCK_ZERO, as follows: + * If BDRV_BLOCK_OFFSET_VALID is set, bits 9-62 (BDRV_BLOCK_OFFSET_MASK) of + * the return value (old interface) or the entire map parameter (new + * interface) represent the offset in the returned BDS that is allocated for + * the corresponding raw data. However, whether that offset actually + * contains data also depends on BDRV_BLOCK_DATA, as follows: * * DATA ZERO OFFSET_VALID * t t t sectors read as zero, returned file is zero at offset @@ -421,9 +422,9 @@ int bdrv_has_zero_init_1(BlockDriverState *bs); int bdrv_has_zero_init(BlockDriverState *bs); bool bdrv_unallocated_blocks_are_zero(BlockDriverState *bs); bool bdrv_can_write_zeroes_with_unmap(BlockDriverState *bs); -int64_t bdrv_get_block_status(BlockDriverState *bs, int64_t sector_num, - int nb_sectors, int *pnum, - BlockDriverState **file); +int bdrv_block_status(BlockDriverState *bs, int64_t offset, + int64_t bytes, int64_t *pnum, int64_t *map, + BlockDriverState **file); int64_t bdrv_get_block_status_above(BlockDriverState *bs, BlockDriverState *base, int64_t sector_num, diff --git a/qemu-img.c b/qemu-img.c index af3effdec5..c81d6ce733 100644 --- a/qemu-img.c +++ b/qemu-img.c @@ -1599,9 +1599,14 @@ static int convert_iteration_sectors(ImgConvertState *s, int64_t sector_num) if (s->sector_next_status <= sector_num) { if (s->target_has_backing) { - ret = bdrv_get_block_status(blk_bs(s->src[src_cur]), - sector_num - src_cur_offset, - n, &n, NULL); + int64_t count = n * BDRV_SECTOR_SIZE; + + ret = bdrv_block_status(blk_bs(s->src[src_cur]), + (sector_num - src_cur_offset) * + BDRV_SECTOR_SIZE, + count, &count, NULL, NULL); + assert(ret < 0 || QEMU_IS_ALIGNED(count, BDRV_SECTOR_SIZE)); + n = count >> BDRV_SECTOR_BITS; } else { ret = bdrv_get_block_status_above(blk_bs(s->src[src_cur]), NULL, sector_num - src_cur_offset, @@ -2674,13 +2679,12 @@ static void dump_map_entry(OutputFormat output_format, MapEntry *e, static int get_block_status(BlockDriverState *bs, int64_t offset, int64_t bytes, MapEntry *e) { - int64_t ret; + int ret; int depth; BlockDriverState *file; bool has_offset; - int nb_sectors = bytes >> BDRV_SECTOR_BITS; + int64_t map; - assert(bytes < INT_MAX); /* As an optimization, we could cache the current range of unallocated * clusters in each file of the chain, and avoid querying the same * range repeatedly. @@ -2688,12 +2692,11 @@ static int get_block_status(BlockDriverState *bs, int64_t offset, depth = 0; for (;;) { - ret = bdrv_get_block_status(bs, offset >> BDRV_SECTOR_BITS, nb_sectors, - &nb_sectors, &file); + ret = bdrv_block_status(bs, offset, bytes, &bytes, &map, &file); if (ret < 0) { return ret; } - assert(nb_sectors); + assert(bytes); if (ret & (BDRV_BLOCK_ZERO|BDRV_BLOCK_DATA)) { break; } @@ -2710,10 +2713,10 @@ static int get_block_status(BlockDriverState *bs, int64_t offset, *e = (MapEntry) { .start = offset, - .length = nb_sectors * BDRV_SECTOR_SIZE, + .length = bytes, .data = !!(ret & BDRV_BLOCK_DATA), .zero = !!(ret & BDRV_BLOCK_ZERO), - .offset = ret & BDRV_BLOCK_OFFSET_MASK, + .offset = map, .has_offset = has_offset, .depth = depth, .has_filename = file && has_offset, |