diff options
Diffstat (limited to 'block/io.c')
| -rw-r--r-- | block/io.c | 57 |
1 files changed, 41 insertions, 16 deletions
diff --git a/block/io.c b/block/io.c index 93231b0e26..8ba408c813 100644 --- a/block/io.c +++ b/block/io.c @@ -1769,10 +1769,11 @@ int bdrv_flush_all(void) typedef struct BdrvCoGetBlockStatusData { BlockDriverState *bs; BlockDriverState *base; - BlockDriverState **file; + bool want_zero; int64_t sector_num; int nb_sectors; int *pnum; + BlockDriverState **file; int64_t ret; bool done; } BdrvCoGetBlockStatusData; @@ -1808,6 +1809,11 @@ int64_t coroutine_fn bdrv_co_get_block_status_from_backing(BlockDriverState *bs, * Drivers not implementing the functionality are assumed to not support * backing files, hence all their sectors are reported as allocated. * + * If 'want_zero' is true, the caller is querying for mapping purposes, + * and the result should include BDRV_BLOCK_OFFSET_VALID and + * BDRV_BLOCK_ZERO where possible; otherwise, the result may omit those + * bits particularly if it allows for a larger value in 'pnum'. + * * If 'sector_num' is beyond the end of the disk image the return value is * BDRV_BLOCK_EOF and 'pnum' is set to 0. * @@ -1824,6 +1830,7 @@ int64_t coroutine_fn bdrv_co_get_block_status_from_backing(BlockDriverState *bs, * is allocated in. */ static int64_t coroutine_fn bdrv_co_get_block_status(BlockDriverState *bs, + bool want_zero, int64_t sector_num, int nb_sectors, int *pnum, BlockDriverState **file) @@ -1878,31 +1885,34 @@ static int64_t coroutine_fn bdrv_co_get_block_status(BlockDriverState *bs, if (ret & BDRV_BLOCK_RAW) { assert(ret & BDRV_BLOCK_OFFSET_VALID && local_file); - ret = bdrv_co_get_block_status(local_file, ret >> BDRV_SECTOR_BITS, + ret = bdrv_co_get_block_status(local_file, want_zero, + ret >> BDRV_SECTOR_BITS, *pnum, pnum, &local_file); goto out; } if (ret & (BDRV_BLOCK_DATA | BDRV_BLOCK_ZERO)) { ret |= BDRV_BLOCK_ALLOCATED; - } else { + } else if (want_zero) { if (bdrv_unallocated_blocks_are_zero(bs)) { ret |= BDRV_BLOCK_ZERO; } else if (bs->backing) { BlockDriverState *bs2 = bs->backing->bs; int64_t nb_sectors2 = bdrv_nb_sectors(bs2); + if (nb_sectors2 >= 0 && sector_num >= nb_sectors2) { ret |= BDRV_BLOCK_ZERO; } } } - if (local_file && local_file != bs && + if (want_zero && local_file && local_file != bs && (ret & BDRV_BLOCK_DATA) && !(ret & BDRV_BLOCK_ZERO) && (ret & BDRV_BLOCK_OFFSET_VALID)) { int file_pnum; - ret2 = bdrv_co_get_block_status(local_file, ret >> BDRV_SECTOR_BITS, + ret2 = bdrv_co_get_block_status(local_file, want_zero, + ret >> BDRV_SECTOR_BITS, *pnum, &file_pnum, NULL); if (ret2 >= 0) { /* Ignore errors. This is just providing extra information, it @@ -1938,6 +1948,7 @@ early_out: static int64_t coroutine_fn bdrv_co_get_block_status_above(BlockDriverState *bs, BlockDriverState *base, + bool want_zero, int64_t sector_num, int nb_sectors, int *pnum, @@ -1949,7 +1960,8 @@ static int64_t coroutine_fn bdrv_co_get_block_status_above(BlockDriverState *bs, assert(bs != base); for (p = bs; p != base; p = backing_bs(p)) { - ret = bdrv_co_get_block_status(p, sector_num, nb_sectors, pnum, file); + ret = bdrv_co_get_block_status(p, want_zero, sector_num, nb_sectors, + pnum, file); if (ret < 0) { break; } @@ -1979,6 +1991,7 @@ static void coroutine_fn bdrv_get_block_status_above_co_entry(void *opaque) BdrvCoGetBlockStatusData *data = opaque; data->ret = bdrv_co_get_block_status_above(data->bs, data->base, + data->want_zero, data->sector_num, data->nb_sectors, data->pnum, @@ -1991,20 +2004,22 @@ static void coroutine_fn bdrv_get_block_status_above_co_entry(void *opaque) * * See bdrv_co_get_block_status_above() for details. */ -int64_t bdrv_get_block_status_above(BlockDriverState *bs, - BlockDriverState *base, - int64_t sector_num, - int nb_sectors, int *pnum, - BlockDriverState **file) +static int64_t bdrv_common_block_status_above(BlockDriverState *bs, + BlockDriverState *base, + bool want_zero, + int64_t sector_num, + int nb_sectors, int *pnum, + BlockDriverState **file) { Coroutine *co; BdrvCoGetBlockStatusData data = { .bs = bs, .base = base, - .file = file, + .want_zero = want_zero, .sector_num = sector_num, .nb_sectors = nb_sectors, .pnum = pnum, + .file = file, .done = false, }; @@ -2020,6 +2035,16 @@ int64_t bdrv_get_block_status_above(BlockDriverState *bs, return data.ret; } +int64_t bdrv_get_block_status_above(BlockDriverState *bs, + BlockDriverState *base, + int64_t sector_num, + int nb_sectors, int *pnum, + BlockDriverState **file) +{ + return bdrv_common_block_status_above(bs, base, true, sector_num, + nb_sectors, pnum, file); +} + int64_t bdrv_get_block_status(BlockDriverState *bs, int64_t sector_num, int nb_sectors, int *pnum, @@ -2032,15 +2057,15 @@ int64_t bdrv_get_block_status(BlockDriverState *bs, int coroutine_fn bdrv_is_allocated(BlockDriverState *bs, int64_t offset, int64_t bytes, int64_t *pnum) { - int64_t sector_num = offset >> BDRV_SECTOR_BITS; - int nb_sectors = bytes >> BDRV_SECTOR_BITS; int64_t ret; int psectors; assert(QEMU_IS_ALIGNED(offset, BDRV_SECTOR_SIZE)); assert(QEMU_IS_ALIGNED(bytes, BDRV_SECTOR_SIZE) && bytes < INT_MAX); - ret = bdrv_get_block_status(bs, sector_num, nb_sectors, &psectors, - NULL); + ret = bdrv_common_block_status_above(bs, backing_bs(bs), false, + offset >> BDRV_SECTOR_BITS, + bytes >> BDRV_SECTOR_BITS, &psectors, + NULL); if (ret < 0) { return ret; } |