From bd31c214c328bc6a2b2f5567623d964b65c8f44c Mon Sep 17 00:00:00 2001 From: Eric Blake Date: Fri, 6 May 2016 10:26:42 -0600 Subject: nbd: Switch to byte-based block access Sector-based blk_read() should die; switch to byte-based blk_pread() instead. Add a constant for our magic number 512, to make it obvious that this size will NOT change even if BDRV_SECTOR_SIZE does, even though the two happen to be the same for now. Split assignments from conditionals to keep checkpatch.pl happy. Signed-off-by: Eric Blake Signed-off-by: Kevin Wolf --- qemu-nbd.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) (limited to 'qemu-nbd.c') diff --git a/qemu-nbd.c b/qemu-nbd.c index c55b40ffc8..3e541131f4 100644 --- a/qemu-nbd.c +++ b/qemu-nbd.c @@ -46,6 +46,8 @@ #define QEMU_NBD_OPT_TLSCREDS 261 #define QEMU_NBD_OPT_IMAGE_OPTS 262 +#define MBR_SIZE 512 + static NBDExport *exp; static bool newproto; static int verbose; @@ -159,12 +161,13 @@ static int find_partition(BlockBackend *blk, int partition, off_t *offset, off_t *size) { struct partition_record mbr[4]; - uint8_t data[512]; + uint8_t data[MBR_SIZE]; int i; int ext_partnum = 4; int ret; - if ((ret = blk_read(blk, 0, data, 1)) < 0) { + ret = blk_pread(blk, 0, data, sizeof(data)); + if (ret < 0) { error_report("error while reading: %s", strerror(-ret)); exit(EXIT_FAILURE); } @@ -182,10 +185,12 @@ static int find_partition(BlockBackend *blk, int partition, if (mbr[i].system == 0xF || mbr[i].system == 0x5) { struct partition_record ext[4]; - uint8_t data1[512]; + uint8_t data1[MBR_SIZE]; int j; - if ((ret = blk_read(blk, mbr[i].start_sector_abs, data1, 1)) < 0) { + ret = blk_pread(blk, mbr[i].start_sector_abs * MBR_SIZE, + data1, sizeof(data1)); + if (ret < 0) { error_report("error while reading: %s", strerror(-ret)); exit(EXIT_FAILURE); } -- cgit v1.2.3