# HG changeset patch
# User kfraser@xxxxxxxxxxxxxxxxxxxxx
# Date 1189526523 -3600
# Node ID 5352a7cc4f2ab3e5b79cfb8d8a25a670946d41dd
# Parent 2e4912a256a43e5e2d85212b980883ddbb538511
[QEMU] Enhance raw io reliability
For raw block device only :
log any I/O error and perform automatic read retry for CDrom
(improves MediaCheck with old installers).
Signed-off-by: Ben Guthro <bguthro@xxxxxxxxxxxxxxx>
Signed-off-by: Josh Nicholas <jnicholas@xxxxxxxxxxxxxxx>
---
tools/ioemu/block-raw.c | 94 ++++++++++++++++++++++++++++++++++++++++++++++--
1 files changed, 92 insertions(+), 2 deletions(-)
diff -r 2e4912a256a4 -r 5352a7cc4f2a tools/ioemu/block-raw.c
--- a/tools/ioemu/block-raw.c Tue Sep 11 17:00:25 2007 +0100
+++ b/tools/ioemu/block-raw.c Tue Sep 11 17:02:03 2007 +0100
@@ -59,6 +59,13 @@
//#define DEBUG_FLOPPY
+#define DEBUG_BLOCK
+#ifdef DEBUG_BLOCK
+#define DEBUG_BLOCK_PRINT( formatCstr, args... ) fprintf( logfile, formatCstr,
##args ); fflush( logfile )
+#else
+#define DEBUG_BLOCK_PRINT( formatCstr, args... )
+#endif
+
#define FTYPE_FILE 0
#define FTYPE_CD 1
#define FTYPE_FD 2
@@ -70,6 +77,7 @@ typedef struct BDRVRawState {
typedef struct BDRVRawState {
int fd;
int type;
+ unsigned int lseek_err_cnt;
#if defined(__linux__)
/* linux floppy specific */
int fd_open_flags;
@@ -87,6 +95,8 @@ static int raw_open(BlockDriverState *bs
BDRVRawState *s = bs->opaque;
int fd, open_flags, ret;
+ s->lseek_err_cnt = 0;
+
open_flags = O_BINARY;
if ((flags & BDRV_O_ACCESS) == O_RDWR) {
open_flags |= O_RDWR;
@@ -137,8 +147,58 @@ static int raw_pread(BlockDriverState *b
if (ret < 0)
return ret;
- lseek(s->fd, offset, SEEK_SET);
+ if (lseek(s->fd, offset, SEEK_SET) == (off_t)-1) {
+ ++(s->lseek_err_cnt);
+ if(s->lseek_err_cnt <= 10) {
+ DEBUG_BLOCK_PRINT("raw_pread(%d:%s, %ld, %p, %d) [%ld] lseek
failed : %d = %s\n",
+ s->fd,
+ bs->filename,
+ offset,
+ buf,
+ count,
+ bs->total_sectors, errno, strerror(errno) );
+ }
+ return -1;
+ }
+ s->lseek_err_cnt=0;
+
ret = read(s->fd, buf, count);
+ if (ret == count)
+ goto label__raw_read__success;
+
+ DEBUG_BLOCK_PRINT("raw_read(%d:%s, %ld, %p, %d) [%ld] read failed %d : %d
= %s\n",
+ s->fd,
+ bs->filename,
+ offset,
+ buf,
+ count,
+ bs->total_sectors,
+ ret, errno, strerror(errno) );
+
+ if (bs->type == BDRV_TYPE_CDROM) { // Try harder for CDrom
+ lseek(s->fd, offset, SEEK_SET);
+ ret = read(s->fd, buf, count);
+ if (ret == count)
+ goto label__raw_read__success;
+ lseek(s->fd, offset, SEEK_SET);
+ ret = read(s->fd, buf, count);
+ if (ret == count)
+ goto label__raw_read__success;
+
+ DEBUG_BLOCK_PRINT("raw_read(%d:%s, %ld, %p, %d) [%ld] retry read
failed %d : %d = %s\n",
+ s->fd,
+ bs->filename,
+ offset,
+ buf,
+ count,
+ bs->total_sectors,
+ ret, errno, strerror(errno) );
+ }
+
+ return -1;
+
+label__raw_read__success:
+
return ret;
}
@@ -152,8 +212,38 @@ static int raw_pwrite(BlockDriverState *
if (ret < 0)
return ret;
- lseek(s->fd, offset, SEEK_SET);
+ if (lseek(s->fd, offset, SEEK_SET) == (off_t)-1) {
+ ++(s->lseek_err_cnt);
+ if(s->lseek_err_cnt) {
+ DEBUG_BLOCK_PRINT("raw_write(%d:%s, %ld, %p, %d) [%ld] lseek
failed : %d = %s\n",
+ s->fd,
+ bs->filename,
+ offset,
+ buf,
+ count,
+ bs->total_sectors, errno, strerror(errno) );
+ }
+ return -1;
+ }
+ s->lseek_err_cnt = 0;
+
ret = write(s->fd, buf, count);
+ if (ret == count)
+ goto label__raw_write__success;
+
+ DEBUG_BLOCK_PRINT("raw_write(%d:%s, %ld, %p, %d) [%ld] write failed %d :
%d = %s\n",
+ s->fd,
+ bs->filename,
+ offset,
+ buf,
+ count,
+ bs->total_sectors,
+ ret, errno, strerror(errno) );
+
+ return -1;
+
+label__raw_write__success:
+
return ret;
}
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