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envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=2a00:1450:4864:20::633; envelope-from=paolo.bonzini@gmail.com; helo=mail-ej1-x633.google.com X-Spam_score_int: -14 X-Spam_score: -1.5 X-Spam_bar: - X-Spam_report: (-1.5 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_FORGED_FROMDOMAIN=0.25, FREEMAIL_FROM=0.001, HEADER_FROM_DIFFERENT_DOMAINS=0.249, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: fam@euphon.net, qemu-block@nongnu.org, mreitz@redhat.com Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) Content-Type: text/plain; charset="utf-8" bs->sg is only true for character devices, but block devices can also be used with scsi-block and scsi-generic. Unfortunately BLKSECTGET returns bytes for /dev/sgN devices and sectors for block devices, so account for that in the code. The maximum transfer also need not be a power of 2 (for example I have seen disks with 1280 KiB maximum transfer) so there's no need to pass the result through pow2floor. Signed-off-by: Paolo Bonzini --- block/file-posix.c | 27 +++++++++++++-------------- 1 file changed, 13 insertions(+), 14 deletions(-) diff --git a/block/file-posix.c b/block/file-posix.c index 9e316a2a97..e37a6bb8de 100644 --- a/block/file-posix.c +++ b/block/file-posix.c @@ -1173,13 +1173,13 @@ static void raw_reopen_abort(BDRVReopenState *state) s->reopen_state =3D NULL; } =20 -static int sg_get_max_transfer_length(int fd) +static int sg_get_max_transfer_length(int fd, struct stat *st) { #ifdef BLKSECTGET int max_bytes =3D 0; =20 if (ioctl(fd, BLKSECTGET, &max_bytes) =3D=3D 0) { - return max_bytes; + return S_ISBLK(st->st_mode) ? max_bytes * 512 : max_bytes; } else { return -errno; } @@ -1188,7 +1188,7 @@ static int sg_get_max_transfer_length(int fd) #endif } =20 -static int sg_get_max_segments(int fd) +static int sg_get_max_segments(int fd, struct stat *st) { #ifdef CONFIG_LINUX char buf[32]; @@ -1197,15 +1197,9 @@ static int sg_get_max_segments(int fd) int ret; int sysfd =3D -1; long max_segments; - struct stat st; - - if (fstat(fd, &st)) { - ret =3D -errno; - goto out; - } =20 sysfspath =3D g_strdup_printf("/sys/dev/block/%u:%u/queue/max_segments= ", - major(st.st_rdev), minor(st.st_rdev)); + major(st->st_rdev), minor(st->st_rdev)); sysfd =3D open(sysfspath, O_RDONLY); if (sysfd =3D=3D -1) { ret =3D -errno; @@ -1242,15 +1236,20 @@ out: static void raw_refresh_limits(BlockDriverState *bs, Error **errp) { BDRVRawState *s =3D bs->opaque; + struct stat st; + + if (fstat(s->fd, &st)) { + return; + } =20 - if (bs->sg) { - int ret =3D sg_get_max_transfer_length(s->fd); + if (bs->sg || S_ISBLK(st.st_mode)) { + int ret =3D sg_get_max_transfer_length(s->fd, &st); =20 if (ret > 0 && ret <=3D BDRV_REQUEST_MAX_BYTES) { - bs->bl.max_transfer =3D pow2floor(ret); + bs->bl.max_transfer =3D ret; } =20 - ret =3D sg_get_max_segments(s->fd); + ret =3D sg_get_max_segments(s->fd, &st); if (ret > 0) { bs->bl.max_iov =3D ret; } --=20 2.30.1