From 2ffca4f3ee6c2d507c39689e5f569bcb0612d3ad Mon Sep 17 00:00:00 2001 From: Philipp Reisner Date: Thu, 30 Jun 2011 15:43:06 +0200 Subject: [PATCH] drbd: Improve compatibility with drbd's older than 8.3.7 Regression introduced with 8.3.11 commit: drbd: Take a more conservative approach when deciding max_bio_size Never ever tell an older drbd, that we support more than 32KiB in a single data request (packet). Never believe an older drbd, that is supports more than 32KiB in a single data request (packet) Signed-off-by: Philipp Reisner Signed-off-by: Lars Ellenberg --- drivers/block/drbd/drbd_int.h | 3 ++- drivers/block/drbd/drbd_main.c | 6 ++++++ drivers/block/drbd/drbd_nl.c | 7 +++++-- 3 files changed, 13 insertions(+), 3 deletions(-) diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h index 1d71b3a..6035784 100644 --- a/drivers/block/drbd/drbd_int.h +++ b/drivers/block/drbd/drbd_int.h @@ -1284,7 +1284,8 @@ struct bm_extent { #endif #define DRBD_MAX_BIO_SIZE_SAFE (1 << 12) /* Works always = 4k */ -#define DRBD_MAX_SIZE_H80_PACKET (1 << 15) /* The old header only allows packets up to 32Kib data */ +#define DRBD_MAX_SIZE_H80_PACKET (1 << 15) /* Header 80 only allows packets up to 32KiB data */ +#define DRBD_MAX_BIO_SIZE_P95 (1 << 17) /* Protocol 95 to 99 allows bios up to 128KiB */ extern int drbd_bm_init(struct drbd_conf *mdev); extern int drbd_bm_resize(struct drbd_conf *mdev, sector_t sectors, int set_new_bits); diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c index 72b1dfa..448de7b 100644 --- a/drivers/block/drbd/drbd_main.c +++ b/drivers/block/drbd/drbd_main.c @@ -1075,6 +1075,12 @@ int drbd_send_sizes(struct drbd_conf *mdev, int trigger_reply, enum dds_flags fl p = drbd_prepare_command(mdev, sock); if (!p) return -EIO; + + if (mdev->tconn->agreed_pro_version <= 94) + max_bio_size = min_t(int, max_bio_size, DRBD_MAX_SIZE_H80_PACKET); + else if (mdev->tconn->agreed_pro_version < 100) + max_bio_size = min_t(int, max_bio_size, DRBD_MAX_BIO_SIZE_P95); + p->d_size = cpu_to_be64(d_size); p->u_size = cpu_to_be64(u_size); p->c_size = cpu_to_be64(trigger_reply ? 0 : drbd_get_capacity(mdev->this_bdev)); diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c index f923462..838c3cd 100644 --- a/drivers/block/drbd/drbd_nl.c +++ b/drivers/block/drbd/drbd_nl.c @@ -1062,10 +1062,13 @@ void drbd_reconsider_max_bio_size(struct drbd_conf *mdev) BIOs for a single peer_request */ if (mdev->state.conn >= C_CONNECTED) { if (mdev->tconn->agreed_pro_version < 94) - peer = mdev->peer_max_bio_size; + peer = min_t(int, mdev->peer_max_bio_size, DRBD_MAX_SIZE_H80_PACKET); + /* Correct old drbd (up to 8.3.7) if it believes it can do more than 32KiB */ else if (mdev->tconn->agreed_pro_version == 94) peer = DRBD_MAX_SIZE_H80_PACKET; - else /* drbd 8.3.8 onwards */ + else if (mdev->tconn->agreed_pro_version < 100) + peer = DRBD_MAX_BIO_SIZE_P95; /* drbd 8.3.8 onwards, before 8.4.0 */ + else peer = DRBD_MAX_BIO_SIZE; } -- 2.7.4