From 285a58d9b83f4f04b2c25d68a867d7aac5226195 Mon Sep 17 00:00:00 2001 From: Kevin Wolf Date: Tue, 14 Feb 2012 11:13:30 +0100 Subject: [PATCH 05/99] cloop: use qemu block API RH-Author: Kevin Wolf Message-id: <1329218101-24213-6-git-send-email-kwolf@redhat.com> Patchwork-id: 37196 O-Subject: [RHEL-6.3 qemu-kvm PATCH v2 05/96] cloop: use qemu block API Bugzilla: 783950 RH-Acked-by: Paolo Bonzini RH-Acked-by: Marcelo Tosatti RH-Acked-by: Laszlo Ersek From: Christoph Hellwig Bugzilla: 783950 Use bdrv_pwrite to access the backing device instead of pread, and convert the driver to implementing the bdrv_open method which gives it an already opened BlockDriverState for the underlying device. Signed-off-by: Christoph Hellwig Signed-off-by: Kevin Wolf (cherry picked from commit 20be49e47e82f1b9fdc33810e1c4d7121871eafa) --- block/cloop.c | 26 ++++++++++++-------------- 1 files changed, 12 insertions(+), 14 deletions(-) Signed-off-by: Michal Novotny --- block/cloop.c | 26 ++++++++++++-------------- 1 files changed, 12 insertions(+), 14 deletions(-) diff --git a/block/cloop.c b/block/cloop.c index 9fe2a42..fe015c4 100644 --- a/block/cloop.c +++ b/block/cloop.c @@ -27,7 +27,6 @@ #include typedef struct BDRVCloopState { - int fd; uint32_t block_size; uint32_t n_blocks; uint64_t* offsets; @@ -51,23 +50,20 @@ static int cloop_probe(const uint8_t *buf, int buf_size, const char *filename) return 0; } -static int cloop_open(BlockDriverState *bs, const char *filename, int flags) +static int cloop_open(BlockDriverState *bs, int flags) { BDRVCloopState *s = bs->opaque; uint32_t offsets_size,max_compressed_block_size=1,i; - s->fd = open(filename, O_RDONLY | O_BINARY); - if (s->fd < 0) - return -errno; bs->read_only = 1; /* read header */ - if (pread(s->fd, &s->block_size, 4, 128) < 4) { + if (bdrv_pread(bs->file, 128, &s->block_size, 4) < 4) { goto cloop_close; } s->block_size = be32_to_cpu(s->block_size); - if (pread(s->fd, &s->n_blocks, 4, 128 + 4) < 4) { + if (bdrv_pread(bs->file, 128 + 4, &s->n_blocks, 4) < 4) { goto cloop_close; } s->n_blocks = be32_to_cpu(s->n_blocks); @@ -75,7 +71,8 @@ static int cloop_open(BlockDriverState *bs, const char *filename, int flags) /* read offsets */ offsets_size = s->n_blocks * sizeof(uint64_t); s->offsets = qemu_malloc(offsets_size); - if (pread(s->fd, s->offsets, offsets_size, 128 + 4 + 4) < offsets_size) { + if (bdrv_pread(bs->file, 128 + 4 + 4, s->offsets, offsets_size) < + offsets_size) { goto cloop_close; } for(i=0;in_blocks;i++) { @@ -99,17 +96,19 @@ static int cloop_open(BlockDriverState *bs, const char *filename, int flags) return 0; cloop_close: - close(s->fd); return -1; } -static inline int cloop_read_block(BDRVCloopState *s,int block_num) +static inline int cloop_read_block(BlockDriverState *bs, int block_num) { + BDRVCloopState *s = bs->opaque; + if(s->current_block != block_num) { int ret; uint32_t bytes = s->offsets[block_num+1]-s->offsets[block_num]; - ret = pread(s->fd, s->compressed_block, bytes, s->offsets[block_num]); + ret = bdrv_pread(bs->file, s->offsets[block_num], s->compressed_block, + bytes); if (ret != bytes) return -1; @@ -138,7 +137,7 @@ static int cloop_read(BlockDriverState *bs, int64_t sector_num, for(i=0;isectors_per_block), block_num=(sector_num+i)/s->sectors_per_block; - if(cloop_read_block(s, block_num) != 0) + if(cloop_read_block(bs, block_num) != 0) return -1; memcpy(buf+i*512,s->uncompressed_block+sector_offset_in_block*512,512); } @@ -148,7 +147,6 @@ static int cloop_read(BlockDriverState *bs, int64_t sector_num, static void cloop_close(BlockDriverState *bs) { BDRVCloopState *s = bs->opaque; - close(s->fd); if(s->n_blocks>0) free(s->offsets); free(s->compressed_block); @@ -160,7 +158,7 @@ static BlockDriver bdrv_cloop = { .format_name = "cloop", .instance_size = sizeof(BDRVCloopState), .bdrv_probe = cloop_probe, - .bdrv_file_open = cloop_open, + .bdrv_open = cloop_open, .bdrv_read = cloop_read, .bdrv_close = cloop_close, }; -- 1.7.7.5