From: Dave Chinner Date: Mon, 12 Aug 2013 10:49:40 +0000 (+1000) Subject: xfs: split out the remote symlink handling X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=1fb7e48db6810093012873a652062648ace6b5bb;p=linux-beck.git xfs: split out the remote symlink handling The remote symlink format definition and manipulation needs to be shared with userspace, but the in-kernel interfaces do not. Split the remote symlink format handling out into xfs_symlink_remote.[ch] fo it can easily be shared with userspace. Signed-off-by: Dave Chinner Reviewed-by: Mark Tinguely Signed-off-by: Ben Myers --- diff --git a/fs/xfs/Makefile b/fs/xfs/Makefile index a73af1c8f978..20b1d949b090 100644 --- a/fs/xfs/Makefile +++ b/fs/xfs/Makefile @@ -50,6 +50,7 @@ xfs-y += xfs_aops.o \ xfs_mru_cache.o \ xfs_rename.o \ xfs_super.o \ + xfs_symlink.o \ xfs_trans.o \ xfs_utils.o \ xfs_vnodeops.o \ @@ -81,7 +82,7 @@ xfs-y += xfs_alloc.o \ xfs_inode_buf.o \ xfs_log_recover.o \ xfs_mount.o \ - xfs_symlink.o \ + xfs_symlink_remote.o \ xfs_trans_resv.o # low-level transaction/log code diff --git a/fs/xfs/xfs_format.h b/fs/xfs/xfs_format.h index 62053744a0a6..35c08ff54ca0 100644 --- a/fs/xfs/xfs_format.h +++ b/fs/xfs/xfs_format.h @@ -27,6 +27,12 @@ * xfs_log_format.h. Everything else goes here. */ +struct xfs_mount; +struct xfs_trans; +struct xfs_inode; +struct xfs_buf; +struct xfs_ifork; + /* * RealTime Device format definitions */ @@ -123,5 +129,41 @@ typedef struct xfs_dqblk { #define XFS_DQUOT_CRC_OFF offsetof(struct xfs_dqblk, dd_crc) +/* + * Remote symlink format and access functions. + */ +#define XFS_SYMLINK_MAGIC 0x58534c4d /* XSLM */ + +struct xfs_dsymlink_hdr { + __be32 sl_magic; + __be32 sl_offset; + __be32 sl_bytes; + __be32 sl_crc; + uuid_t sl_uuid; + __be64 sl_owner; + __be64 sl_blkno; + __be64 sl_lsn; +}; + +/* + * The maximum pathlen is 1024 bytes. Since the minimum file system + * blocksize is 512 bytes, we can get a max of 3 extents back from + * bmapi when crc headers are taken into account. + */ +#define XFS_SYMLINK_MAPS 3 + +#define XFS_SYMLINK_BUF_SPACE(mp, bufsize) \ + ((bufsize) - (xfs_sb_version_hascrc(&(mp)->m_sb) ? \ + sizeof(struct xfs_dsymlink_hdr) : 0)) + +int xfs_symlink_blocks(struct xfs_mount *mp, int pathlen); +int xfs_symlink_hdr_set(struct xfs_mount *mp, xfs_ino_t ino, uint32_t offset, + uint32_t size, struct xfs_buf *bp); +bool xfs_symlink_hdr_ok(struct xfs_mount *mp, xfs_ino_t ino, uint32_t offset, + uint32_t size, struct xfs_buf *bp); +void xfs_symlink_local_to_remote(struct xfs_trans *tp, struct xfs_buf *bp, + struct xfs_inode *ip, struct xfs_ifork *ifp); + +extern const struct xfs_buf_ops xfs_symlink_buf_ops; #endif /* __XFS_FORMAT_H__ */ diff --git a/fs/xfs/xfs_symlink.c b/fs/xfs/xfs_symlink.c index dd7c0991fdb9..18f24de4dc2a 100644 --- a/fs/xfs/xfs_symlink.c +++ b/fs/xfs/xfs_symlink.c @@ -32,8 +32,6 @@ #include "xfs_ialloc_btree.h" #include "xfs_dinode.h" #include "xfs_inode.h" -#include "xfs_inode_item.h" -#include "xfs_itable.h" #include "xfs_ialloc.h" #include "xfs_alloc.h" #include "xfs_bmap.h" @@ -41,178 +39,8 @@ #include "xfs_quota.h" #include "xfs_utils.h" #include "xfs_trans_space.h" -#include "xfs_log_priv.h" #include "xfs_trace.h" #include "xfs_symlink.h" -#include "xfs_cksum.h" -#include "xfs_buf_item.h" - - -/* - * Each contiguous block has a header, so it is not just a simple pathlen - * to FSB conversion. - */ -int -xfs_symlink_blocks( - struct xfs_mount *mp, - int pathlen) -{ - int buflen = XFS_SYMLINK_BUF_SPACE(mp, mp->m_sb.sb_blocksize); - - return (pathlen + buflen - 1) / buflen; -} - -static int -xfs_symlink_hdr_set( - struct xfs_mount *mp, - xfs_ino_t ino, - uint32_t offset, - uint32_t size, - struct xfs_buf *bp) -{ - struct xfs_dsymlink_hdr *dsl = bp->b_addr; - - if (!xfs_sb_version_hascrc(&mp->m_sb)) - return 0; - - dsl->sl_magic = cpu_to_be32(XFS_SYMLINK_MAGIC); - dsl->sl_offset = cpu_to_be32(offset); - dsl->sl_bytes = cpu_to_be32(size); - uuid_copy(&dsl->sl_uuid, &mp->m_sb.sb_uuid); - dsl->sl_owner = cpu_to_be64(ino); - dsl->sl_blkno = cpu_to_be64(bp->b_bn); - bp->b_ops = &xfs_symlink_buf_ops; - - return sizeof(struct xfs_dsymlink_hdr); -} - -/* - * Checking of the symlink header is split into two parts. the verifier does - * CRC, location and bounds checking, the unpacking function checks the path - * parameters and owner. - */ -bool -xfs_symlink_hdr_ok( - struct xfs_mount *mp, - xfs_ino_t ino, - uint32_t offset, - uint32_t size, - struct xfs_buf *bp) -{ - struct xfs_dsymlink_hdr *dsl = bp->b_addr; - - if (offset != be32_to_cpu(dsl->sl_offset)) - return false; - if (size != be32_to_cpu(dsl->sl_bytes)) - return false; - if (ino != be64_to_cpu(dsl->sl_owner)) - return false; - - /* ok */ - return true; -} - -static bool -xfs_symlink_verify( - struct xfs_buf *bp) -{ - struct xfs_mount *mp = bp->b_target->bt_mount; - struct xfs_dsymlink_hdr *dsl = bp->b_addr; - - if (!xfs_sb_version_hascrc(&mp->m_sb)) - return false; - if (dsl->sl_magic != cpu_to_be32(XFS_SYMLINK_MAGIC)) - return false; - if (!uuid_equal(&dsl->sl_uuid, &mp->m_sb.sb_uuid)) - return false; - if (bp->b_bn != be64_to_cpu(dsl->sl_blkno)) - return false; - if (be32_to_cpu(dsl->sl_offset) + - be32_to_cpu(dsl->sl_bytes) >= MAXPATHLEN) - return false; - if (dsl->sl_owner == 0) - return false; - - return true; -} - -static void -xfs_symlink_read_verify( - struct xfs_buf *bp) -{ - struct xfs_mount *mp = bp->b_target->bt_mount; - - /* no verification of non-crc buffers */ - if (!xfs_sb_version_hascrc(&mp->m_sb)) - return; - - if (!xfs_verify_cksum(bp->b_addr, BBTOB(bp->b_length), - offsetof(struct xfs_dsymlink_hdr, sl_crc)) || - !xfs_symlink_verify(bp)) { - XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr); - xfs_buf_ioerror(bp, EFSCORRUPTED); - } -} - -static void -xfs_symlink_write_verify( - struct xfs_buf *bp) -{ - struct xfs_mount *mp = bp->b_target->bt_mount; - struct xfs_buf_log_item *bip = bp->b_fspriv; - - /* no verification of non-crc buffers */ - if (!xfs_sb_version_hascrc(&mp->m_sb)) - return; - - if (!xfs_symlink_verify(bp)) { - XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr); - xfs_buf_ioerror(bp, EFSCORRUPTED); - return; - } - - if (bip) { - struct xfs_dsymlink_hdr *dsl = bp->b_addr; - dsl->sl_lsn = cpu_to_be64(bip->bli_item.li_lsn); - } - xfs_update_cksum(bp->b_addr, BBTOB(bp->b_length), - offsetof(struct xfs_dsymlink_hdr, sl_crc)); -} - -const struct xfs_buf_ops xfs_symlink_buf_ops = { - .verify_read = xfs_symlink_read_verify, - .verify_write = xfs_symlink_write_verify, -}; - -void -xfs_symlink_local_to_remote( - struct xfs_trans *tp, - struct xfs_buf *bp, - struct xfs_inode *ip, - struct xfs_ifork *ifp) -{ - struct xfs_mount *mp = ip->i_mount; - char *buf; - - if (!xfs_sb_version_hascrc(&mp->m_sb)) { - bp->b_ops = NULL; - memcpy(bp->b_addr, ifp->if_u1.if_data, ifp->if_bytes); - return; - } - - /* - * As this symlink fits in an inode literal area, it must also fit in - * the smallest buffer the filesystem supports. - */ - ASSERT(BBTOB(bp->b_length) >= - ifp->if_bytes + sizeof(struct xfs_dsymlink_hdr)); - - bp->b_ops = &xfs_symlink_buf_ops; - - buf = bp->b_addr; - buf += xfs_symlink_hdr_set(mp, ip->i_ino, 0, ifp->if_bytes, bp); - memcpy(buf, ifp->if_u1.if_data, ifp->if_bytes); -} /* ----- Kernel only functions below ----- */ STATIC int diff --git a/fs/xfs/xfs_symlink.h b/fs/xfs/xfs_symlink.h index c8e3a02f0344..99338ba666ac 100644 --- a/fs/xfs/xfs_symlink.h +++ b/fs/xfs/xfs_symlink.h @@ -17,51 +17,11 @@ #ifndef __XFS_SYMLINK_H #define __XFS_SYMLINK_H 1 -struct xfs_mount; -struct xfs_trans; -struct xfs_inode; -struct xfs_buf; -struct xfs_ifork; -struct xfs_name; - -#define XFS_SYMLINK_MAGIC 0x58534c4d /* XSLM */ - -struct xfs_dsymlink_hdr { - __be32 sl_magic; - __be32 sl_offset; - __be32 sl_bytes; - __be32 sl_crc; - uuid_t sl_uuid; - __be64 sl_owner; - __be64 sl_blkno; - __be64 sl_lsn; -}; - -/* - * The maximum pathlen is 1024 bytes. Since the minimum file system - * blocksize is 512 bytes, we can get a max of 3 extents back from - * bmapi when crc headers are taken into account. - */ -#define XFS_SYMLINK_MAPS 3 - -#define XFS_SYMLINK_BUF_SPACE(mp, bufsize) \ - ((bufsize) - (xfs_sb_version_hascrc(&(mp)->m_sb) ? \ - sizeof(struct xfs_dsymlink_hdr) : 0)) - -int xfs_symlink_blocks(struct xfs_mount *mp, int pathlen); -bool xfs_symlink_hdr_ok(struct xfs_mount *mp, xfs_ino_t ino, uint32_t offset, - uint32_t size, struct xfs_buf *bp); -void xfs_symlink_local_to_remote(struct xfs_trans *tp, struct xfs_buf *bp, - struct xfs_inode *ip, struct xfs_ifork *ifp); - -extern const struct xfs_buf_ops xfs_symlink_buf_ops; - -#ifdef __KERNEL__ +/* Kernel only symlink defintions */ int xfs_symlink(struct xfs_inode *dp, struct xfs_name *link_name, const char *target_path, umode_t mode, struct xfs_inode **ipp); int xfs_readlink(struct xfs_inode *ip, char *link); int xfs_inactive_symlink(struct xfs_inode *ip, struct xfs_trans **tpp); -#endif /* __KERNEL__ */ #endif /* __XFS_SYMLINK_H */ diff --git a/fs/xfs/xfs_symlink_remote.c b/fs/xfs/xfs_symlink_remote.c new file mode 100644 index 000000000000..a31852471885 --- /dev/null +++ b/fs/xfs/xfs_symlink_remote.c @@ -0,0 +1,199 @@ +/* + * Copyright (c) 2000-2006 Silicon Graphics, Inc. + * Copyright (c) 2012-2013 Red Hat, Inc. + * All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it would be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ +#include "xfs.h" +#include "xfs_fs.h" +#include "xfs_format.h" +#include "xfs_log.h" +#include "xfs_trans.h" +#include "xfs_sb.h" +#include "xfs_mount.h" +#include "xfs_bmap_btree.h" +#include "xfs_inode.h" +#include "xfs_error.h" +#include "xfs_trace.h" +#include "xfs_symlink.h" +#include "xfs_cksum.h" +#include "xfs_buf_item.h" + + +/* + * Each contiguous block has a header, so it is not just a simple pathlen + * to FSB conversion. + */ +int +xfs_symlink_blocks( + struct xfs_mount *mp, + int pathlen) +{ + int buflen = XFS_SYMLINK_BUF_SPACE(mp, mp->m_sb.sb_blocksize); + + return (pathlen + buflen - 1) / buflen; +} + +int +xfs_symlink_hdr_set( + struct xfs_mount *mp, + xfs_ino_t ino, + uint32_t offset, + uint32_t size, + struct xfs_buf *bp) +{ + struct xfs_dsymlink_hdr *dsl = bp->b_addr; + + if (!xfs_sb_version_hascrc(&mp->m_sb)) + return 0; + + dsl->sl_magic = cpu_to_be32(XFS_SYMLINK_MAGIC); + dsl->sl_offset = cpu_to_be32(offset); + dsl->sl_bytes = cpu_to_be32(size); + uuid_copy(&dsl->sl_uuid, &mp->m_sb.sb_uuid); + dsl->sl_owner = cpu_to_be64(ino); + dsl->sl_blkno = cpu_to_be64(bp->b_bn); + bp->b_ops = &xfs_symlink_buf_ops; + + return sizeof(struct xfs_dsymlink_hdr); +} + +/* + * Checking of the symlink header is split into two parts. the verifier does + * CRC, location and bounds checking, the unpacking function checks the path + * parameters and owner. + */ +bool +xfs_symlink_hdr_ok( + struct xfs_mount *mp, + xfs_ino_t ino, + uint32_t offset, + uint32_t size, + struct xfs_buf *bp) +{ + struct xfs_dsymlink_hdr *dsl = bp->b_addr; + + if (offset != be32_to_cpu(dsl->sl_offset)) + return false; + if (size != be32_to_cpu(dsl->sl_bytes)) + return false; + if (ino != be64_to_cpu(dsl->sl_owner)) + return false; + + /* ok */ + return true; +} + +static bool +xfs_symlink_verify( + struct xfs_buf *bp) +{ + struct xfs_mount *mp = bp->b_target->bt_mount; + struct xfs_dsymlink_hdr *dsl = bp->b_addr; + + if (!xfs_sb_version_hascrc(&mp->m_sb)) + return false; + if (dsl->sl_magic != cpu_to_be32(XFS_SYMLINK_MAGIC)) + return false; + if (!uuid_equal(&dsl->sl_uuid, &mp->m_sb.sb_uuid)) + return false; + if (bp->b_bn != be64_to_cpu(dsl->sl_blkno)) + return false; + if (be32_to_cpu(dsl->sl_offset) + + be32_to_cpu(dsl->sl_bytes) >= MAXPATHLEN) + return false; + if (dsl->sl_owner == 0) + return false; + + return true; +} + +static void +xfs_symlink_read_verify( + struct xfs_buf *bp) +{ + struct xfs_mount *mp = bp->b_target->bt_mount; + + /* no verification of non-crc buffers */ + if (!xfs_sb_version_hascrc(&mp->m_sb)) + return; + + if (!xfs_verify_cksum(bp->b_addr, BBTOB(bp->b_length), + offsetof(struct xfs_dsymlink_hdr, sl_crc)) || + !xfs_symlink_verify(bp)) { + XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr); + xfs_buf_ioerror(bp, EFSCORRUPTED); + } +} + +static void +xfs_symlink_write_verify( + struct xfs_buf *bp) +{ + struct xfs_mount *mp = bp->b_target->bt_mount; + struct xfs_buf_log_item *bip = bp->b_fspriv; + + /* no verification of non-crc buffers */ + if (!xfs_sb_version_hascrc(&mp->m_sb)) + return; + + if (!xfs_symlink_verify(bp)) { + XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr); + xfs_buf_ioerror(bp, EFSCORRUPTED); + return; + } + + if (bip) { + struct xfs_dsymlink_hdr *dsl = bp->b_addr; + dsl->sl_lsn = cpu_to_be64(bip->bli_item.li_lsn); + } + xfs_update_cksum(bp->b_addr, BBTOB(bp->b_length), + offsetof(struct xfs_dsymlink_hdr, sl_crc)); +} + +const struct xfs_buf_ops xfs_symlink_buf_ops = { + .verify_read = xfs_symlink_read_verify, + .verify_write = xfs_symlink_write_verify, +}; + +void +xfs_symlink_local_to_remote( + struct xfs_trans *tp, + struct xfs_buf *bp, + struct xfs_inode *ip, + struct xfs_ifork *ifp) +{ + struct xfs_mount *mp = ip->i_mount; + char *buf; + + if (!xfs_sb_version_hascrc(&mp->m_sb)) { + bp->b_ops = NULL; + memcpy(bp->b_addr, ifp->if_u1.if_data, ifp->if_bytes); + return; + } + + /* + * As this symlink fits in an inode literal area, it must also fit in + * the smallest buffer the filesystem supports. + */ + ASSERT(BBTOB(bp->b_length) >= + ifp->if_bytes + sizeof(struct xfs_dsymlink_hdr)); + + bp->b_ops = &xfs_symlink_buf_ops; + + buf = bp->b_addr; + buf += xfs_symlink_hdr_set(mp, ip->i_ino, 0, ifp->if_bytes, bp); + memcpy(buf, ifp->if_u1.if_data, ifp->if_bytes); +}