aboutsummaryrefslogtreecommitdiff
path: root/block
diff options
context:
space:
mode:
Diffstat (limited to 'block')
-rw-r--r--block/file-posix.c54
1 files changed, 28 insertions, 26 deletions
diff --git a/block/file-posix.c b/block/file-posix.c
index ab05b51a66..4479cc7ab4 100644
--- a/block/file-posix.c
+++ b/block/file-posix.c
@@ -1038,15 +1038,13 @@ static void raw_reopen_abort(BDRVReopenState *state)
s->reopen_state = NULL;
}
-static int hdev_get_max_transfer_length(BlockDriverState *bs, int fd)
+static int sg_get_max_transfer_length(int fd)
{
#ifdef BLKSECTGET
int max_bytes = 0;
- short max_sectors = 0;
- if (bs->sg && ioctl(fd, BLKSECTGET, &max_bytes) == 0) {
+
+ if (ioctl(fd, BLKSECTGET, &max_bytes) == 0) {
return max_bytes;
- } else if (!bs->sg && ioctl(fd, BLKSECTGET, &max_sectors) == 0) {
- return max_sectors << BDRV_SECTOR_BITS;
} else {
return -errno;
}
@@ -1055,25 +1053,31 @@ static int hdev_get_max_transfer_length(BlockDriverState *bs, int fd)
#endif
}
-static int hdev_get_max_segments(const struct stat *st)
+static int sg_get_max_segments(int fd)
{
#ifdef CONFIG_LINUX
char buf[32];
const char *end;
- char *sysfspath;
+ char *sysfspath = NULL;
int ret;
- int fd = -1;
+ int sysfd = -1;
long max_segments;
+ struct stat st;
+
+ if (fstat(fd, &st)) {
+ ret = -errno;
+ goto out;
+ }
sysfspath = g_strdup_printf("/sys/dev/block/%u:%u/queue/max_segments",
- major(st->st_rdev), minor(st->st_rdev));
- fd = open(sysfspath, O_RDONLY);
- if (fd == -1) {
+ major(st.st_rdev), minor(st.st_rdev));
+ sysfd = open(sysfspath, O_RDONLY);
+ if (sysfd == -1) {
ret = -errno;
goto out;
}
do {
- ret = read(fd, buf, sizeof(buf) - 1);
+ ret = read(sysfd, buf, sizeof(buf) - 1);
} while (ret == -1 && errno == EINTR);
if (ret < 0) {
ret = -errno;
@@ -1090,8 +1094,8 @@ static int hdev_get_max_segments(const struct stat *st)
}
out:
- if (fd != -1) {
- close(fd);
+ if (sysfd != -1) {
+ close(sysfd);
}
g_free(sysfspath);
return ret;
@@ -1103,19 +1107,17 @@ out:
static void raw_refresh_limits(BlockDriverState *bs, Error **errp)
{
BDRVRawState *s = bs->opaque;
- struct stat st;
- if (!fstat(s->fd, &st)) {
- if (S_ISBLK(st.st_mode) || S_ISCHR(st.st_mode)) {
- int ret = hdev_get_max_transfer_length(bs, s->fd);
- if (ret > 0 && ret <= BDRV_REQUEST_MAX_BYTES) {
- bs->bl.max_transfer = pow2floor(ret);
- }
- ret = hdev_get_max_segments(&st);
- if (ret > 0) {
- bs->bl.max_transfer = MIN(bs->bl.max_transfer,
- ret * getpagesize());
- }
+ if (bs->sg) {
+ int ret = sg_get_max_transfer_length(s->fd);
+
+ if (ret > 0 && ret <= BDRV_REQUEST_MAX_BYTES) {
+ bs->bl.max_transfer = pow2floor(ret);
+ }
+
+ ret = sg_get_max_segments(s->fd);
+ if (ret > 0) {
+ bs->bl.max_transfer = MIN(bs->bl.max_transfer, ret * getpagesize());
}
}