From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: with ECARTIS (v1.0.0; list xfs); Thu, 25 Sep 2008 15:55:19 -0700 (PDT) Received: from cuda.sgi.com (cuda2.sgi.com [192.48.168.29]) by oss.sgi.com (8.12.11.20060308/8.12.11/SuSE Linux 0.7) with ESMTP id m8PMt69V024332 for ; Thu, 25 Sep 2008 15:55:06 -0700 Received: from verein.lst.de (localhost [127.0.0.1]) by cuda.sgi.com (Spam Firewall) with ESMTP id 665F048509F for ; Thu, 25 Sep 2008 15:56:40 -0700 (PDT) Received: from verein.lst.de (verein.lst.de [213.95.11.210]) by cuda.sgi.com with ESMTP id Afve6AJx4SGbuFwX for ; Thu, 25 Sep 2008 15:56:40 -0700 (PDT) Date: Fri, 26 Sep 2008 00:56:39 +0200 From: Christoph Hellwig Subject: [PATCH 6/9] Add CRC checks to the superblock. Message-ID: <20080925225639.GG9822@lst.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline; filename=xfs-sb-crc Sender: xfs-bounce@oss.sgi.com Errors-to: xfs-bounce@oss.sgi.com List-Id: xfs To: xfs@oss.sgi.com Cc: Dave Chinner From: Dave Chinner [hch: minor adaptions] Signed-off-by: Dave Chinner Signed-off-by: Christoph Hellwig Index: linux-2.6-xfs/fs/xfs/xfs_mount.c =================================================================== --- linux-2.6-xfs.orig/fs/xfs/xfs_mount.c 2008-09-26 00:34:28.000000000 +0200 +++ linux-2.6-xfs/fs/xfs/xfs_mount.c 2008-09-26 00:37:32.000000000 +0200 @@ -44,6 +44,7 @@ #include "xfs_quota.h" #include "xfs_fsops.h" #include "xfs_utils.h" +#include "xfs_cksum.h" STATIC int xfs_mount_log_sb(xfs_mount_t *, __int64_t); STATIC int xfs_uuid_mount(xfs_mount_t *); @@ -119,6 +120,8 @@ static const struct { { offsetof(xfs_sb_t, sb_logsunit), 0 }, { offsetof(xfs_sb_t, sb_features2), 0 }, { offsetof(xfs_sb_t, sb_bad_features2), 0 }, + { offsetof(xfs_sb_t, sb_crc), 0 }, + { offsetof(xfs_sb_t, sb_pad), 0 }, { sizeof(xfs_sb_t), 0 } }; @@ -409,6 +412,7 @@ xfs_sb_from_disk( to->sb_logsunit = be32_to_cpu(from->sb_logsunit); to->sb_features2 = be32_to_cpu(from->sb_features2); to->sb_bad_features2 = be32_to_cpu(from->sb_bad_features2); + to->sb_crc = be32_to_cpu(from->sb_crc); } /* @@ -465,6 +469,24 @@ xfs_sb_to_disk( } /* + * Calculate the superblock CRC and stuff it in the buffer. + * + * We get called here just before the superblock is written + * to disk. We should also do some validity checking here. + * + * We CRC the entire superblock sector, not just the bits we use + * so that changes in structure size as features are included do + * not invalidate CRCs. + */ +void +xfs_sb_calc_crc( + struct xfs_buf *bp) +{ + xfs_update_cksum(XFS_BUF_PTR(bp), XFS_BUF_SIZE(bp), + offsetof(struct xfs_sb, sb_crc)); +} + +/* * xfs_readsb * * Does the initial read of the superblock. @@ -475,6 +497,7 @@ xfs_readsb(xfs_mount_t *mp, int flags) unsigned int sector_size; unsigned int extra_flags; xfs_buf_t *bp; + xfs_sb_t *sbp = &mp->m_sb; int error; ASSERT(mp->m_sb_bp == NULL); @@ -504,7 +527,25 @@ xfs_readsb(xfs_mount_t *mp, int flags) */ xfs_sb_from_disk(&mp->m_sb, XFS_BUF_TO_SBP(bp)); - error = xfs_mount_validate_sb(mp, &(mp->m_sb), flags); + /* + * If the superblock has the CRC feature bit set or + * the CRC field is non-null, check that the CRC is valid. + * We check the CRC field is non-null because a single bit + * error could clear the feature bit and unused parts of + * the superblock are supposed to be zero. Hence a non-null + * crc field indicates that we've potentially lost a feature + * bit and we should check it anyway. + */ + if (xfs_sb_version_hascrc(sbp) || sbp->sb_crc != 0) { + if (!xfs_verify_cksum(XFS_BUF_PTR(bp), sbp->sb_sectsize, + offsetof(struct xfs_sb, sb_crc))) { + xfs_fs_mount_cmn_err(flags, "SB CRC check failed"); + error = EFSCORRUPTED; + goto fail; + } + } + + error = xfs_mount_validate_sb(mp, sbp, flags); if (error) { xfs_fs_mount_cmn_err(flags, "SB validate failed"); goto fail; @@ -513,10 +554,10 @@ xfs_readsb(xfs_mount_t *mp, int flags) /* * We must be able to do sector-sized and sector-aligned IO. */ - if (sector_size > mp->m_sb.sb_sectsize) { + if (sector_size > sbp->sb_sectsize) { xfs_fs_mount_cmn_err(flags, "device supports only %u byte sectors (not %u)", - sector_size, mp->m_sb.sb_sectsize); + sector_size, sbp->sb_sectsize); error = ENOSYS; goto fail; } @@ -525,10 +566,10 @@ xfs_readsb(xfs_mount_t *mp, int flags) * If device sector size is smaller than the superblock size, * re-read the superblock so the buffer is correctly sized. */ - if (sector_size < mp->m_sb.sb_sectsize) { + if (sector_size < sbp->sb_sectsize) { XFS_BUF_UNMANAGE(bp); xfs_buf_relse(bp); - sector_size = mp->m_sb.sb_sectsize; + sector_size = sbp->sb_sectsize; bp = xfs_buf_read_flags(mp->m_ddev_targp, XFS_SB_DADDR, BTOBB(sector_size), extra_flags); if (!bp || XFS_BUF_ISERROR(bp)) { @@ -544,11 +585,13 @@ xfs_readsb(xfs_mount_t *mp, int flags) xfs_icsb_reinit_counters(mp); mp->m_sb_bp = bp; + if (xfs_sb_version_hascrc(sbp)) + xfs_buf_set_io_callback(bp, xfs_sb_calc_crc); xfs_buf_relse(bp); ASSERT(XFS_BUF_VALUSEMA(bp) > 0); return 0; - fail: +fail: if (bp) { XFS_BUF_UNMANAGE(bp); xfs_buf_relse(bp); Index: linux-2.6-xfs/fs/xfs/xfs_sb.h =================================================================== --- linux-2.6-xfs.orig/fs/xfs/xfs_sb.h 2008-09-26 00:34:28.000000000 +0200 +++ linux-2.6-xfs/fs/xfs/xfs_sb.h 2008-09-26 00:37:32.000000000 +0200 @@ -159,7 +159,10 @@ typedef struct xfs_sb { */ __uint32_t sb_bad_features2; + __uint32_t sb_crc; /* superblock crc */ + /* must be padded to 64 bit alignment */ + __uint32_t sb_pad; } xfs_sb_t; /* @@ -227,9 +230,12 @@ typedef struct xfs_dsb { * for features2 bits. Easiest just to mark it bad and not use * it for anything else. */ - __be32 sb_bad_features2; + __be32 sb_bad_features2; + + __be32 sb_crc; /* superblock crc */ /* must be padded to 64 bit alignment */ + __be32 sb_pad; } xfs_dsb_t; /* @@ -248,7 +254,7 @@ typedef enum { XFS_SBS_GQUOTINO, XFS_SBS_QFLAGS, XFS_SBS_FLAGS, XFS_SBS_SHARED_VN, XFS_SBS_INOALIGNMT, XFS_SBS_UNIT, XFS_SBS_WIDTH, XFS_SBS_DIRBLKLOG, XFS_SBS_LOGSECTLOG, XFS_SBS_LOGSECTSIZE, XFS_SBS_LOGSUNIT, - XFS_SBS_FEATURES2, XFS_SBS_BAD_FEATURES2, + XFS_SBS_FEATURES2, XFS_SBS_BAD_FEATURES2, XFS_SBS_CRC, XFS_SBS_PAD, XFS_SBS_FIELDCOUNT } xfs_sb_field_t; @@ -274,6 +280,8 @@ typedef enum { #define XFS_SB_FDBLOCKS XFS_SB_MVAL(FDBLOCKS) #define XFS_SB_FEATURES2 XFS_SB_MVAL(FEATURES2) #define XFS_SB_BAD_FEATURES2 XFS_SB_MVAL(BAD_FEATURES2) +#define XFS_SB_CRC XFS_SB_MVAL(CRC) +#define XFS_SB_PAD XFS_SB_MVAL(PAD) #define XFS_SB_NUM_BITS ((int)XFS_SBS_FIELDCOUNT) #define XFS_SB_ALL_BITS ((1LL << XFS_SB_NUM_BITS) - 1) #define XFS_SB_MOD_BITS \ Index: linux-2.6-xfs/fs/xfs/xfs_trans.c =================================================================== --- linux-2.6-xfs.orig/fs/xfs/xfs_trans.c 2008-09-26 00:34:28.000000000 +0200 +++ linux-2.6-xfs/fs/xfs/xfs_trans.c 2008-09-26 00:37:32.000000000 +0200 @@ -44,6 +44,7 @@ #include "xfs_trans_priv.h" #include "xfs_trans_space.h" #include "xfs_inode_item.h" +#include "xfs_cksum.h" STATIC void xfs_trans_apply_sb_deltas(xfs_trans_t *); Index: linux-2.6-xfs/fs/xfs/xfs_mount.h =================================================================== --- linux-2.6-xfs.orig/fs/xfs/xfs_mount.h 2008-09-26 00:34:28.000000000 +0200 +++ linux-2.6-xfs/fs/xfs/xfs_mount.h 2008-09-26 00:37:32.000000000 +0200 @@ -506,6 +506,7 @@ typedef struct xfs_mod_sb { #define XFS_MOUNT_ILOCK(mp) mutex_lock(&((mp)->m_ilock)) #define XFS_MOUNT_IUNLOCK(mp) mutex_unlock(&((mp)->m_ilock)) +extern void xfs_sb_calc_crc(struct xfs_buf *); extern void xfs_mod_sb(xfs_trans_t *, __int64_t); extern int xfs_log_sbcount(xfs_mount_t *, uint); extern int xfs_mountfs(xfs_mount_t *mp); Index: linux-2.6-xfs/fs/xfs/xfs_log_recover.c =================================================================== --- linux-2.6-xfs.orig/fs/xfs/xfs_log_recover.c 2008-09-26 00:35:04.000000000 +0200 +++ linux-2.6-xfs/fs/xfs/xfs_log_recover.c 2008-09-26 00:38:00.000000000 +0200 @@ -1941,6 +1941,9 @@ xlog_recover_do_reg_buffer( case XFS_BMAP_CRC_MAGIC: xfs_btree_lblock_calc_crc(bp); break; + case XFS_SB_MAGIC: + xfs_sb_calc_crc(bp); + break; default: break; } --