[Qemu-devel] [PATCH v5 09/14] nbd: Switch to byte-based block access

[Eric Blake <eblake@redhat.com>]

Sector-based blk_read() should die; switch to byte-based
blk_pread() instead.

Signed-off-by: Eric Blake <eblake@redhat.com>
---
 qemu-nbd.c | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/qemu-nbd.c b/qemu-nbd.c
index c55b40f..c07ceef 100644
--- a/qemu-nbd.c
+++ b/qemu-nbd.c
@@ -159,12 +159,13 @@ 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[BDRV_SECTOR_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 +183,12 @@ 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[BDRV_SECTOR_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 << BDRV_SECTOR_BITS,
+                            data1, sizeof(data1));
+            if (ret < 0) {
                 error_report("error while reading: %s", strerror(-ret));
                 exit(EXIT_FAILURE);
             }
-- 
2.5.5