hw: Fix return value check for bdrv_read, bdrv_write

Those functions return -errno in case of an error.
The old code would typically only detect EPERM (1) errors.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Stefan Hajnoczi <stefanha@gmail.com>

1 files changed, 9 insertions, 7 deletions

diff --git a/hw/sd.c b/hw/sd.c
index ec2640754..297580aab 100644
--- a/hw/sd.c
+++ b/hw/sd.c
@@ -1407,7 +1407,7 @@ static void sd_blk_read(SDState *sd, uint64_t addr, uint32_t len)
 
     DPRINTF("sd_blk_read: addr = 0x%08llx, len = %d\n",
             (unsigned long long) addr, len);
-    if (!sd->bdrv || bdrv_read(sd->bdrv, addr >> 9, sd->buf, 1) == -1) {
+    if (!sd->bdrv || bdrv_read(sd->bdrv, addr >> 9, sd->buf, 1) < 0) {
         fprintf(stderr, "sd_blk_read: read error on host side\n");
         return;
     }
@@ -1415,7 +1415,7 @@ static void sd_blk_read(SDState *sd, uint64_t addr, uint32_t len)
     if (end > (addr & ~511) + 512) {
         memcpy(sd->data, sd->buf + (addr & 511), 512 - (addr & 511));
 
-        if (bdrv_read(sd->bdrv, end >> 9, sd->buf, 1) == -1) {
+        if (bdrv_read(sd->bdrv, end >> 9, sd->buf, 1) < 0) {
             fprintf(stderr, "sd_blk_read: read error on host side\n");
             return;
         }
@@ -1429,29 +1429,31 @@ static void sd_blk_write(SDState *sd, uint64_t addr, uint32_t len)
     uint64_t end = addr + len;
 
     if ((addr & 511) || len < 512)
-        if (!sd->bdrv || bdrv_read(sd->bdrv, addr >> 9, sd->buf, 1) == -1) {
+        if (!sd->bdrv || bdrv_read(sd->bdrv, addr >> 9, sd->buf, 1) < 0) {
             fprintf(stderr, "sd_blk_write: read error on host side\n");
             return;
         }
 
     if (end > (addr & ~511) + 512) {
         memcpy(sd->buf + (addr & 511), sd->data, 512 - (addr & 511));
-        if (bdrv_write(sd->bdrv, addr >> 9, sd->buf, 1) == -1) {
+        if (bdrv_write(sd->bdrv, addr >> 9, sd->buf, 1) < 0) {
             fprintf(stderr, "sd_blk_write: write error on host side\n");
             return;
         }
 
-        if (bdrv_read(sd->bdrv, end >> 9, sd->buf, 1) == -1) {
+        if (bdrv_read(sd->bdrv, end >> 9, sd->buf, 1) < 0) {
             fprintf(stderr, "sd_blk_write: read error on host side\n");
             return;
         }
         memcpy(sd->buf, sd->data + 512 - (addr & 511), end & 511);
-        if (bdrv_write(sd->bdrv, end >> 9, sd->buf, 1) == -1)
+        if (bdrv_write(sd->bdrv, end >> 9, sd->buf, 1) < 0) {
             fprintf(stderr, "sd_blk_write: write error on host side\n");
+        }
     } else {
         memcpy(sd->buf + (addr & 511), sd->data, len);
-        if (!sd->bdrv || bdrv_write(sd->bdrv, addr >> 9, sd->buf, 1) == -1)
+        if (!sd->bdrv || bdrv_write(sd->bdrv, addr >> 9, sd->buf, 1) < 0) {
             fprintf(stderr, "sd_blk_write: write error on host side\n");
+        }
     }
 }