From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from buildserver.ru.mvista.com (unknown [85.21.88.6]) by mail.linbit.com (LINBIT Mail Daemon) with ESMTP id A4CB62E0917E for ; Mon, 26 Nov 2007 14:55:22 +0100 (CET) Received: from [192.168.1.132] (unknown [10.150.0.9]) by buildserver.ru.mvista.com (Postfix) with ESMTP id 082BD8817 for ; Mon, 26 Nov 2007 18:26:51 +0400 (SAMT) Message-ID: <474AF52C.6090409@ru.mvista.com> Date: Mon, 26 Nov 2007 16:32:44 +0000 From: Maxim Uvarov MIME-Version: 1.0 To: drbd-dev@lists.linbit.com Content-Type: multipart/mixed; boundary="------------060105060402050705090800" Subject: [Drbd-dev] [DRBD][PATCH] drbd_bitfild_endian.patch List-Id: Coordination of development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , This is a multi-part message in MIME format. --------------060105060402050705090800 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Hello all, We have found that drbd state is passed incorrectly between machines with different endianness. Attached patch fixes this problem by converting bitfild to int. Replacing all bitfileds (both in kernel and userland) isn't safe way (there are about hundred lines to replace). Maybe adding converter from bitfield to int32 is appropriate solution ? Then sending state we do "drbd_state_to_int(state)" and then receive we restore state by "int_to_drbd_state(i)". only 9 lines of kernel code was changed (No need to change userspace). Additional overhead is neglible. Best regards, Maxim. --------------060105060402050705090800 Content-Type: text/plain; name="drbd_bitfild_endian.patch" Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="drbd_bitfild_endian.patch" Source: MontaVista Software, Inc. MR: 26056 Type: Defect Fix Disposition: needs submitting to DRBD maintainer Signed-off-by: Maxim Uvarov Signed-off-by: Maxim Syrchin Description: DRBD uses bitfield to store its state. Since bitfields are not cross-architecture safe - it causes error then archs of peers are different. The simplest way to solve this is to convert biitfild to cross-arch safe int32. This change makes new protocol incompatile with old one - so PRO_VERSION is increased from 86 up to 88. Index: linux-2.6.21_mvlcge500/drivers/block/drbd/drbd_int.h =================================================================== --- linux-2.6.21_mvlcge500.orig/drivers/block/drbd/drbd_int.h +++ linux-2.6.21_mvlcge500/drivers/block/drbd/drbd_int.h @@ -1446,6 +1446,64 @@ void drbd_bcast_state(drbd_dev *mdev); D,({drbd_state_t ns; ns.i = D->state.i; ns.T1 = (S1); \ ns.T2 = (S2); ns.T3 = (S3); ns;}) +/* + * Using bitfields is no cross-architecture safe. + * Use shifts to convert bitfield to cross-safe int + */ + +#define ROLE_OFF 0 +#define PEER_OFF 2 +#define CONN_OFF 4 +#define DISK_OFF 9 +#define PDSK_OFF 13 +#define SUSP_OFF 17 +#define AISP_OFF 18 +#define PISP_OFF 19 +#define UISP_OFF 20 + +#define ROLE_MASK (unsigned int)0x03 +#define PEER_MASK (unsigned int)0x03 +#define CONN_MASK (unsigned int)0x1f +#define DISK_MASK (unsigned int)0x0f +#define PDSK_MASK (unsigned int)0x0f +#define SUSP_MASK (unsigned int)0x01 +#define AISP_MASK (unsigned int)0x01 +#define PISP_MASK (unsigned int)0x01 +#define UISP_MASK (unsigned int)0x01 + +static inline unsigned int drbd_state_to_int (unsigned int state_i) +{ + unsigned int i = 0; + drbd_state_t state; + state.i = state_i; + i = ((unsigned int)state.role)<>ROLE_OFF)&ROLE_MASK; + state.peer = (i>>PEER_OFF)&PEER_MASK; + state.conn = (i>>CONN_OFF)&CONN_MASK; + state.disk = (i>>DISK_OFF)&DISK_MASK; + state.pdsk = (i>>PDSK_OFF)&PDSK_MASK; + state.susp = (i>>SUSP_OFF)&SUSP_MASK; + state.aftr_isp = (i>>AISP_OFF)&AISP_MASK; + state.peer_isp = (i>>PISP_OFF)&PISP_MASK; + state.user_isp = (i>>UISP_OFF)&UISP_MASK; + return state.i; +} + static inline void drbd_state_lock(drbd_dev *mdev) { wait_event(mdev->misc_wait, Index: linux-2.6.21_mvlcge500/drivers/block/drbd/drbd_main.c =================================================================== --- linux-2.6.21_mvlcge500.orig/drivers/block/drbd/drbd_main.c +++ linux-2.6.21_mvlcge500/drivers/block/drbd/drbd_main.c @@ -1366,7 +1366,7 @@ int drbd_send_state(drbd_dev *mdev) { Drbd_State_Packet p; - p.state = cpu_to_be32(mdev->state.i); + p.state = cpu_to_be32(drbd_state_to_int(mdev->state.i)); return drbd_send_cmd(mdev,USE_DATA_SOCKET,ReportState, (Drbd_Header*)&p,sizeof(p)); @@ -1376,8 +1376,8 @@ STATIC int drbd_send_state_req(drbd_dev { Drbd_Req_State_Packet p; - p.mask = cpu_to_be32(mask.i); - p.val = cpu_to_be32(val.i); + p.mask = cpu_to_be32(drbd_state_to_int(mask.i)); + p.val = cpu_to_be32(drbd_state_to_int(val.i)); return drbd_send_cmd(mdev,USE_DATA_SOCKET,StateChgRequest, (Drbd_Header*)&p,sizeof(p)); @@ -3179,15 +3179,15 @@ _dump_packet(drbd_dev *mdev, struct sock break; case ReportState: - v.i = be32_to_cpu(p->State.state); + v.i = int_to_drbd_state(be32_to_cpu(p->State.state)); m.i = 0xffffffff; dump_st(tmp,sizeof(tmp),m,v); INFOP("%s (s %x {%s})\n", cmdname(cmd), v.i, tmp); break; case StateChgRequest: - m.i = be32_to_cpu(p->ReqState.mask); - v.i = be32_to_cpu(p->ReqState.val); + m.i = int_to_drbd_state(be32_to_cpu(p->ReqState.mask)); + v.i = int_to_drbd_state(be32_to_cpu(p->ReqState.val)); dump_st(tmp,sizeof(tmp),m,v); INFOP("%s (m %x v %x {%s})\n", cmdname(cmd), m.i, v.i, tmp); break; Index: linux-2.6.21_mvlcge500/drivers/block/drbd/drbd_receiver.c =================================================================== --- linux-2.6.21_mvlcge500.orig/drivers/block/drbd/drbd_receiver.c +++ linux-2.6.21_mvlcge500/drivers/block/drbd/drbd_receiver.c @@ -2369,8 +2369,8 @@ STATIC int receive_req_state(drbd_dev *m if (drbd_recv(mdev, h->payload, h->length) != h->length) return FALSE; - mask.i = be32_to_cpu(p->mask); - val.i = be32_to_cpu(p->val); + mask.i = int_to_drbd_state(be32_to_cpu(p->mask)); + val.i = int_to_drbd_state(be32_to_cpu(p->val)); if (test_bit(DISCARD_CONCURRENT,&mdev->flags)) drbd_state_lock(mdev); @@ -2401,7 +2401,7 @@ STATIC int receive_state(drbd_dev *mdev, nconn = mdev->state.conn; if (nconn == WFReportParams ) nconn = Connected; - peer_state.i = be32_to_cpu(p->state); + peer_state.i = int_to_drbd_state(be32_to_cpu(p->state)); if (mdev->p_uuid && mdev->state.conn <= Connected && inc_local_if_state(mdev,Negotiating) && Index: linux-2.6.21_mvlcge500/include/linux/drbd_config.h =================================================================== --- linux-2.6.21_mvlcge500.orig/include/linux/drbd_config.h +++ linux-2.6.21_mvlcge500/include/linux/drbd_config.h @@ -24,7 +24,7 @@ extern const char * drbd_buildtag(void); #define REL_VERSION "8.0.3" #define API_VERSION 86 -#define PRO_VERSION 86 +#define PRO_VERSION 88 // undef if you need the workaround in drbd_receiver #define HAVE_UML_TO_VIRT 1 --------------060105060402050705090800--