From: Dave Chinner <dchinner@xxxxxxxxxx> Add a header to the remote symlink block, containing location and owner information, as well as CRCs and LSN fields. This requires verifiers to be added to the remote symlink buffers for CRC enabled filesystems. This also fixes a bug reading multiple block symlinks, where the second block overwrites the first block when copying out the link name. Signed-off-by: Dave Chinner <dchinner@xxxxxxxxxx> --- fs/xfs/Makefile | 5 +- fs/xfs/xfs_buf_item.h | 4 +- fs/xfs/xfs_log_recover.c | 8 + fs/xfs/xfs_symlink.c | 690 ++++++++++++++++++++++++++++++++++++++++++++++ fs/xfs/xfs_symlink.h | 43 +++ fs/xfs/xfs_vnodeops.c | 480 +------------------------------- 6 files changed, 751 insertions(+), 479 deletions(-) create mode 100644 fs/xfs/xfs_symlink.c create mode 100644 fs/xfs/xfs_symlink.h diff --git a/fs/xfs/Makefile b/fs/xfs/Makefile index d02201d..062f25c 100644 --- a/fs/xfs/Makefile +++ b/fs/xfs/Makefile @@ -45,11 +45,11 @@ xfs-y += xfs_aops.o \ xfs_itable.o \ xfs_message.o \ xfs_mru_cache.o \ - xfs_super.o \ - xfs_xattr.o \ xfs_rename.o \ + xfs_super.o \ xfs_utils.o \ xfs_vnodeops.o \ + xfs_xattr.o \ kmem.o \ uuid.o @@ -73,6 +73,7 @@ xfs-y += xfs_alloc.o \ xfs_inode.o \ xfs_log_recover.o \ xfs_mount.o \ + xfs_symlink.o \ xfs_trans.o # low-level transaction/log code diff --git a/fs/xfs/xfs_buf_item.h b/fs/xfs/xfs_buf_item.h index d1eeeab..298438f 100644 --- a/fs/xfs/xfs_buf_item.h +++ b/fs/xfs/xfs_buf_item.h @@ -50,6 +50,7 @@ extern kmem_zone_t *xfs_buf_item_zone; #define XFS_BLF_AGI_BUF (1<<8) #define XFS_BLF_DINO_BUF (1<<9) #define XFS_BLF_SB_BUF (1<<10) +#define XFS_BLF_SYMLINK_BUF (1<<11) #define XFS_BLF_TYPE_MASK \ (XFS_BLF_UDQUOT_BUF | \ @@ -60,7 +61,8 @@ extern kmem_zone_t *xfs_buf_item_zone; XFS_BLF_AGFL_BUF | \ XFS_BLF_AGI_BUF | \ XFS_BLF_DINO_BUF | \ - XFS_BLF_SB_BUF) + XFS_BLF_SB_BUF | \ + XFS_BLF_SYMLINK_BUF) #define XFS_BLF_CHUNK 128 #define XFS_BLF_SHIFT 7 diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c index a13a47a..b5d4e91 100644 --- a/fs/xfs/xfs_log_recover.c +++ b/fs/xfs/xfs_log_recover.c @@ -45,6 +45,7 @@ #include "xfs_cksum.h" #include "xfs_trace.h" #include "xfs_icache.h" +#include "xfs_symlink.h" STATIC int xlog_find_zeroed( @@ -2006,6 +2007,13 @@ xlog_recover_do_reg_buffer( } bp->b_ops = &xfs_sb_buf_ops; break; + case XFS_BLF_SYMLINK_BUF: + if (*(__be32 *)bp->b_addr != cpu_to_be32(XFS_SYMLINK_MAGIC)) { + xfs_warn(mp, "Bad symlink block magic!"); + ASSERT(0); + } + bp->b_ops = &xfs_symlink_buf_ops; + break; default: break; } diff --git a/fs/xfs/xfs_symlink.c b/fs/xfs/xfs_symlink.c new file mode 100644 index 0000000..1c0660e --- /dev/null +++ b/fs/xfs/xfs_symlink.c @@ -0,0 +1,690 @@ +/* + * Copyright (c) 2000-2006 Silicon Graphics, Inc. + * Copyright 2013 Red Hat, Inc. + * All rights reserved. + */ + +#include "xfs.h" +#include "xfs_fs.h" +#include "xfs_types.h" +#include "xfs_bit.h" +#include "xfs_log.h" +#include "xfs_trans.h" +#include "xfs_sb.h" +#include "xfs_ag.h" +#include "xfs_dir2.h" +#include "xfs_mount.h" +#include "xfs_da_btree.h" +#include "xfs_bmap_btree.h" +#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" +#include "xfs_error.h" +#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 fsblocks = 0; + int len = pathlen; + + do { + fsblocks++; + len -= XFS_SYMLINK_BUF_SPACE(mp, mp->m_sb.sb_blocksize); + } while (len > 0); + + ASSERT(fsblocks <= XFS_SYMLINK_MAPS); + return fsblocks; +} + +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, +}; + + +/* ----- Kernel only functions below ----- */ +STATIC int +xfs_readlink_bmap( + struct xfs_inode *ip, + char *link) +{ + struct xfs_mount *mp = ip->i_mount; + struct xfs_bmbt_irec mval[XFS_SYMLINK_MAPS]; + struct xfs_buf *bp; + xfs_daddr_t d; + char *cur_chunk; + int pathlen = ip->i_d.di_size; + int nmaps = XFS_SYMLINK_MAPS; + int byte_cnt; + int n; + int error = 0; + int fsblocks = 0; + int offset; + + fsblocks = xfs_symlink_blocks(mp, pathlen); + error = xfs_bmapi_read(ip, 0, fsblocks, mval, &nmaps, 0); + if (error) + goto out; + + offset = 0; + for (n = 0; n < nmaps; n++) { + d = XFS_FSB_TO_DADDR(mp, mval[n].br_startblock); + byte_cnt = XFS_FSB_TO_B(mp, mval[n].br_blockcount); + + bp = xfs_buf_read(mp->m_ddev_targp, d, BTOBB(byte_cnt), 0, + &xfs_symlink_buf_ops); + if (!bp) + return XFS_ERROR(ENOMEM); + error = bp->b_error; + if (error) { + xfs_buf_ioerror_alert(bp, __func__); + xfs_buf_relse(bp); + goto out; + } + byte_cnt = XFS_SYMLINK_BUF_SPACE(mp, byte_cnt); + if (pathlen < byte_cnt) + byte_cnt = pathlen; + + cur_chunk = bp->b_addr; + if (xfs_sb_version_hascrc(&mp->m_sb)) { + if (!xfs_symlink_hdr_ok(mp, ip->i_ino, offset, + byte_cnt, bp)) { + error = EFSCORRUPTED; + xfs_alert(mp, +"symlink header does not match required off/len/owner (0x%x/Ox%x,0x%llx)", + offset, byte_cnt, ip->i_ino); + xfs_buf_relse(bp); + goto out; + + } + + cur_chunk += sizeof(struct xfs_dsymlink_hdr); + } + + memcpy(link + offset, bp->b_addr, byte_cnt); + + pathlen -= byte_cnt; + offset += byte_cnt; + + xfs_buf_relse(bp); + } + ASSERT(pathlen == 0); + + link[ip->i_d.di_size] = '\0'; + error = 0; + + out: + return error; +} + +int +xfs_readlink( + struct xfs_inode *ip, + char *link) +{ + struct xfs_mount *mp = ip->i_mount; + xfs_fsize_t pathlen; + int error = 0; + + trace_xfs_readlink(ip); + + if (XFS_FORCED_SHUTDOWN(mp)) + return XFS_ERROR(EIO); + + xfs_ilock(ip, XFS_ILOCK_SHARED); + + pathlen = ip->i_d.di_size; + if (!pathlen) + goto out; + + if (pathlen < 0 || pathlen > MAXPATHLEN) { + xfs_alert(mp, "%s: inode (%llu) bad symlink length (%lld)", + __func__, (unsigned long long) ip->i_ino, + (long long) pathlen); + ASSERT(0); + error = XFS_ERROR(EFSCORRUPTED); + goto out; + } + + + if (ip->i_df.if_flags & XFS_IFINLINE) { + memcpy(link, ip->i_df.if_u1.if_data, pathlen); + link[pathlen] = '\0'; + } else { + error = xfs_readlink_bmap(ip, link); + } + + out: + xfs_iunlock(ip, XFS_ILOCK_SHARED); + return error; +} + +int +xfs_symlink( + struct xfs_inode *dp, + struct xfs_name *link_name, + const char *target_path, + umode_t mode, + struct xfs_inode **ipp) +{ + struct xfs_mount *mp = dp->i_mount; + struct xfs_trans *tp = NULL; + struct xfs_inode *ip = NULL; + int error = 0; + int pathlen; + struct xfs_bmap_free free_list; + xfs_fsblock_t first_block; + bool unlock_dp_on_error = false; + uint cancel_flags; + int committed; + xfs_fileoff_t first_fsb; + xfs_filblks_t fs_blocks; + int nmaps; + struct xfs_bmbt_irec mval[XFS_SYMLINK_MAPS]; + xfs_daddr_t d; + const char *cur_chunk; + int byte_cnt; + int n; + xfs_buf_t *bp; + prid_t prid; + struct xfs_dquot *udqp, *gdqp; + uint resblks; + + *ipp = NULL; + + trace_xfs_symlink(dp, link_name); + + if (XFS_FORCED_SHUTDOWN(mp)) + return XFS_ERROR(EIO); + + /* + * Check component lengths of the target path name. + */ + pathlen = strlen(target_path); + if (pathlen >= MAXPATHLEN) /* total string too long */ + return XFS_ERROR(ENAMETOOLONG); + + udqp = gdqp = NULL; + if (dp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) + prid = xfs_get_projid(dp); + else + prid = XFS_PROJID_DEFAULT; + + /* + * Make sure that we have allocated dquot(s) on disk. + */ + error = xfs_qm_vop_dqalloc(dp, current_fsuid(), current_fsgid(), prid, + XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT, &udqp, &gdqp); + if (error) + goto std_return; + + tp = xfs_trans_alloc(mp, XFS_TRANS_SYMLINK); + cancel_flags = XFS_TRANS_RELEASE_LOG_RES; + /* + * The symlink will fit into the inode data fork? + * There can't be any attributes so we get the whole variable part. + */ + if (pathlen <= XFS_LITINO(mp, dp->i_d.di_version)) + fs_blocks = 0; + else + fs_blocks = XFS_B_TO_FSB(mp, pathlen); + resblks = XFS_SYMLINK_SPACE_RES(mp, link_name->len, fs_blocks); + error = xfs_trans_reserve(tp, resblks, XFS_SYMLINK_LOG_RES(mp), 0, + XFS_TRANS_PERM_LOG_RES, XFS_SYMLINK_LOG_COUNT); + if (error == ENOSPC && fs_blocks == 0) { + resblks = 0; + error = xfs_trans_reserve(tp, 0, XFS_SYMLINK_LOG_RES(mp), 0, + XFS_TRANS_PERM_LOG_RES, XFS_SYMLINK_LOG_COUNT); + } + if (error) { + cancel_flags = 0; + goto error_return; + } + + xfs_ilock(dp, XFS_ILOCK_EXCL | XFS_ILOCK_PARENT); + unlock_dp_on_error = true; + + /* + * Check whether the directory allows new symlinks or not. + */ + if (dp->i_d.di_flags & XFS_DIFLAG_NOSYMLINKS) { + error = XFS_ERROR(EPERM); + goto error_return; + } + + /* + * Reserve disk quota : blocks and inode. + */ + error = xfs_trans_reserve_quota(tp, mp, udqp, gdqp, resblks, 1, 0); + if (error) + goto error_return; + + /* + * Check for ability to enter directory entry, if no space reserved. + */ + error = xfs_dir_canenter(tp, dp, link_name, resblks); + if (error) + goto error_return; + /* + * Initialize the bmap freelist prior to calling either + * bmapi or the directory create code. + */ + xfs_bmap_init(&free_list, &first_block); + + /* + * Allocate an inode for the symlink. + */ + error = xfs_dir_ialloc(&tp, dp, S_IFLNK | (mode & ~S_IFMT), 1, 0, + prid, resblks > 0, &ip, NULL); + if (error) { + if (error == ENOSPC) + goto error_return; + goto error1; + } + + /* + * An error after we've joined dp to the transaction will result in the + * transaction cancel unlocking dp so don't do it explicitly in the + * error path. + */ + xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL); + unlock_dp_on_error = false; + + /* + * Also attach the dquot(s) to it, if applicable. + */ + xfs_qm_vop_create_dqattach(tp, ip, udqp, gdqp); + + if (resblks) + resblks -= XFS_IALLOC_SPACE_RES(mp); + /* + * If the symlink will fit into the inode, write it inline. + */ + if (pathlen <= XFS_IFORK_DSIZE(ip)) { + xfs_idata_realloc(ip, pathlen, XFS_DATA_FORK); + memcpy(ip->i_df.if_u1.if_data, target_path, pathlen); + ip->i_d.di_size = pathlen; + + /* + * The inode was initially created in extent format. + */ + ip->i_df.if_flags &= ~(XFS_IFEXTENTS | XFS_IFBROOT); + ip->i_df.if_flags |= XFS_IFINLINE; + + ip->i_d.di_format = XFS_DINODE_FMT_LOCAL; + xfs_trans_log_inode(tp, ip, XFS_ILOG_DDATA | XFS_ILOG_CORE); + + } else { + int offset; + + first_fsb = 0; + nmaps = XFS_SYMLINK_MAPS; + + error = xfs_bmapi_write(tp, ip, first_fsb, fs_blocks, + XFS_BMAPI_METADATA, &first_block, resblks, + mval, &nmaps, &free_list); + if (error) + goto error2; + + if (resblks) + resblks -= fs_blocks; + ip->i_d.di_size = pathlen; + xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); + + cur_chunk = target_path; + offset = 0; + for (n = 0; n < nmaps; n++) { + char *buf; + + d = XFS_FSB_TO_DADDR(mp, mval[n].br_startblock); + byte_cnt = XFS_FSB_TO_B(mp, mval[n].br_blockcount); + bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, d, + BTOBB(byte_cnt), 0); + if (!bp) { + error = ENOMEM; + goto error2; + } + bp->b_ops = &xfs_symlink_buf_ops; + + byte_cnt = XFS_SYMLINK_BUF_SPACE(mp, byte_cnt); + if (pathlen < byte_cnt) { + byte_cnt = pathlen; + } + + buf = bp->b_addr; + buf += xfs_symlink_hdr_set(mp, ip->i_ino, offset, + byte_cnt, bp); + + memcpy(buf, cur_chunk, byte_cnt); + + cur_chunk += byte_cnt; + pathlen -= byte_cnt; + offset += byte_cnt; + + xfs_trans_log_buf(tp, bp, 0, + (buf + byte_cnt) - (char *)bp->b_addr); + } + } + + /* + * Create the directory entry for the symlink. + */ + error = xfs_dir_createname(tp, dp, link_name, ip->i_ino, + &first_block, &free_list, resblks); + if (error) + goto error2; + xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG); + xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE); + + /* + * If this is a synchronous mount, make sure that the + * symlink transaction goes to disk before returning to + * the user. + */ + if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC)) { + xfs_trans_set_sync(tp); + } + + error = xfs_bmap_finish(&tp, &free_list, &committed); + if (error) { + goto error2; + } + error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES); + xfs_qm_dqrele(udqp); + xfs_qm_dqrele(gdqp); + + *ipp = ip; + return 0; + + error2: + IRELE(ip); + error1: + xfs_bmap_cancel(&free_list); + cancel_flags |= XFS_TRANS_ABORT; + error_return: + xfs_trans_cancel(tp, cancel_flags); + xfs_qm_dqrele(udqp); + xfs_qm_dqrele(gdqp); + + if (unlock_dp_on_error) + xfs_iunlock(dp, XFS_ILOCK_EXCL); + std_return: + return error; +} + +/* + * Free a symlink that has blocks associated with it. + */ +int +xfs_inactive_symlink_rmt( + xfs_inode_t *ip, + xfs_trans_t **tpp) +{ + xfs_buf_t *bp; + int committed; + int done; + int error; + xfs_fsblock_t first_block; + xfs_bmap_free_t free_list; + int i; + xfs_mount_t *mp; + xfs_bmbt_irec_t mval[XFS_SYMLINK_MAPS]; + int nmaps; + xfs_trans_t *ntp; + int size; + xfs_trans_t *tp; + + tp = *tpp; + mp = ip->i_mount; + ASSERT(ip->i_d.di_size > XFS_IFORK_DSIZE(ip)); + /* + * We're freeing a symlink that has some + * blocks allocated to it. Free the + * blocks here. We know that we've got + * either 1 or 2 extents and that we can + * free them all in one bunmapi call. + */ + ASSERT(ip->i_d.di_nextents > 0 && ip->i_d.di_nextents <= 2); + + /* + * Lock the inode, fix the size, and join it to the transaction. + * Hold it so in the normal path, we still have it locked for + * the second transaction. In the error paths we need it + * held so the cancel won't rele it, see below. + */ + size = (int)ip->i_d.di_size; + ip->i_d.di_size = 0; + xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); + /* + * Find the block(s) so we can inval and unmap them. + */ + done = 0; + xfs_bmap_init(&free_list, &first_block); + nmaps = ARRAY_SIZE(mval); + error = xfs_bmapi_read(ip, 0, xfs_symlink_blocks(mp, size), + mval, &nmaps, 0); + if (error) + goto error0; + /* + * Invalidate the block(s). No validation is done. + */ + for (i = 0; i < nmaps; i++) { + bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, + XFS_FSB_TO_DADDR(mp, mval[i].br_startblock), + XFS_FSB_TO_BB(mp, mval[i].br_blockcount), 0); + if (!bp) { + error = ENOMEM; + goto error1; + } + xfs_trans_binval(tp, bp); + } + /* + * Unmap the dead block(s) to the free_list. + */ + if ((error = xfs_bunmapi(tp, ip, 0, size, XFS_BMAPI_METADATA, nmaps, + &first_block, &free_list, &done))) + goto error1; + ASSERT(done); + /* + * Commit the first transaction. This logs the EFI and the inode. + */ + if ((error = xfs_bmap_finish(&tp, &free_list, &committed))) + goto error1; + /* + * The transaction must have been committed, since there were + * actually extents freed by xfs_bunmapi. See xfs_bmap_finish. + * The new tp has the extent freeing and EFDs. + */ + ASSERT(committed); + /* + * The first xact was committed, so add the inode to the new one. + * Mark it dirty so it will be logged and moved forward in the log as + * part of every commit. + */ + xfs_trans_ijoin(tp, ip, 0); + xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); + /* + * Get a new, empty transaction to return to our caller. + */ + ntp = xfs_trans_dup(tp); + /* + * Commit the transaction containing extent freeing and EFDs. + * If we get an error on the commit here or on the reserve below, + * we need to unlock the inode since the new transaction doesn't + * have the inode attached. + */ + error = xfs_trans_commit(tp, 0); + tp = ntp; + if (error) { + ASSERT(XFS_FORCED_SHUTDOWN(mp)); + goto error0; + } + /* + * transaction commit worked ok so we can drop the extra ticket + * reference that we gained in xfs_trans_dup() + */ + xfs_log_ticket_put(tp->t_ticket); + + /* + * Remove the memory for extent descriptions (just bookkeeping). + */ + if (ip->i_df.if_bytes) + xfs_idata_realloc(ip, -ip->i_df.if_bytes, XFS_DATA_FORK); + ASSERT(ip->i_df.if_bytes == 0); + /* + * Put an itruncate log reservation in the new transaction + * for our caller. + */ + if ((error = xfs_trans_reserve(tp, 0, XFS_ITRUNCATE_LOG_RES(mp), 0, + XFS_TRANS_PERM_LOG_RES, XFS_ITRUNCATE_LOG_COUNT))) { + ASSERT(XFS_FORCED_SHUTDOWN(mp)); + goto error0; + } + + xfs_trans_ijoin(tp, ip, 0); + *tpp = tp; + return 0; + + error1: + xfs_bmap_cancel(&free_list); + error0: + return error; +} diff --git a/fs/xfs/xfs_symlink.h b/fs/xfs/xfs_symlink.h new file mode 100644 index 0000000..bb21e6a --- /dev/null +++ b/fs/xfs/xfs_symlink.h @@ -0,0 +1,43 @@ +/* + * Copyright (c) 2012 Red Hat, Inc. All rights reserved. + */ +#ifndef __XFS_SYMLINK_H +#define __XFS_SYMLINK_H 1 + +#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); + +extern const struct xfs_buf_ops xfs_symlink_buf_ops; + +#ifdef __KERNEL__ + +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_rmt(struct xfs_inode *ip, struct xfs_trans **tpp); + +#endif /* __KERNEL__ */ +#endif /* __XFS_SYMLINK_H */ diff --git a/fs/xfs/xfs_vnodeops.c b/fs/xfs/xfs_vnodeops.c index aa0c066..1034440 100644 --- a/fs/xfs/xfs_vnodeops.c +++ b/fs/xfs/xfs_vnodeops.c @@ -1,5 +1,6 @@ /* * Copyright (c) 2000-2006 Silicon Graphics, Inc. + * Copyright (c) 2012 Red Hat, Inc. * All Rights Reserved. * * This program is free software; you can redistribute it and/or @@ -48,103 +49,10 @@ #include "xfs_vnodeops.h" #include "xfs_trace.h" #include "xfs_icache.h" +#include "xfs_symlink.h" +#include "xfs_cksum.h" +#include "xfs_buf_item.h" -/* - * The maximum pathlen is 1024 bytes. Since the minimum file system - * blocksize is 512 bytes, we can get a max of 2 extents back from - * bmapi. - */ -#define SYMLINK_MAPS 2 - -STATIC int -xfs_readlink_bmap( - xfs_inode_t *ip, - char *link) -{ - xfs_mount_t *mp = ip->i_mount; - int pathlen = ip->i_d.di_size; - int nmaps = SYMLINK_MAPS; - xfs_bmbt_irec_t mval[SYMLINK_MAPS]; - xfs_daddr_t d; - int byte_cnt; - int n; - xfs_buf_t *bp; - int error = 0; - - error = xfs_bmapi_read(ip, 0, XFS_B_TO_FSB(mp, pathlen), mval, &nmaps, - 0); - if (error) - goto out; - - for (n = 0; n < nmaps; n++) { - d = XFS_FSB_TO_DADDR(mp, mval[n].br_startblock); - byte_cnt = XFS_FSB_TO_B(mp, mval[n].br_blockcount); - - bp = xfs_buf_read(mp->m_ddev_targp, d, BTOBB(byte_cnt), 0, NULL); - if (!bp) - return XFS_ERROR(ENOMEM); - error = bp->b_error; - if (error) { - xfs_buf_ioerror_alert(bp, __func__); - xfs_buf_relse(bp); - goto out; - } - if (pathlen < byte_cnt) - byte_cnt = pathlen; - pathlen -= byte_cnt; - - memcpy(link, bp->b_addr, byte_cnt); - xfs_buf_relse(bp); - } - - link[ip->i_d.di_size] = '\0'; - error = 0; - - out: - return error; -} - -int -xfs_readlink( - xfs_inode_t *ip, - char *link) -{ - xfs_mount_t *mp = ip->i_mount; - xfs_fsize_t pathlen; - int error = 0; - - trace_xfs_readlink(ip); - - if (XFS_FORCED_SHUTDOWN(mp)) - return XFS_ERROR(EIO); - - xfs_ilock(ip, XFS_ILOCK_SHARED); - - pathlen = ip->i_d.di_size; - if (!pathlen) - goto out; - - if (pathlen < 0 || pathlen > MAXPATHLEN) { - xfs_alert(mp, "%s: inode (%llu) bad symlink length (%lld)", - __func__, (unsigned long long) ip->i_ino, - (long long) pathlen); - ASSERT(0); - error = XFS_ERROR(EFSCORRUPTED); - goto out; - } - - - if (ip->i_df.if_flags & XFS_IFINLINE) { - memcpy(link, ip->i_df.if_u1.if_data, pathlen); - link[pathlen] = '\0'; - } else { - error = xfs_readlink_bmap(ip, link); - } - - out: - xfs_iunlock(ip, XFS_ILOCK_SHARED); - return error; -} /* * This is called by xfs_inactive to free any blocks beyond eof @@ -249,145 +157,6 @@ xfs_free_eofblocks( return error; } -/* - * Free a symlink that has blocks associated with it. - */ -STATIC int -xfs_inactive_symlink_rmt( - xfs_inode_t *ip, - xfs_trans_t **tpp) -{ - xfs_buf_t *bp; - int committed; - int done; - int error; - xfs_fsblock_t first_block; - xfs_bmap_free_t free_list; - int i; - xfs_mount_t *mp; - xfs_bmbt_irec_t mval[SYMLINK_MAPS]; - int nmaps; - xfs_trans_t *ntp; - int size; - xfs_trans_t *tp; - - tp = *tpp; - mp = ip->i_mount; - ASSERT(ip->i_d.di_size > XFS_IFORK_DSIZE(ip)); - /* - * We're freeing a symlink that has some - * blocks allocated to it. Free the - * blocks here. We know that we've got - * either 1 or 2 extents and that we can - * free them all in one bunmapi call. - */ - ASSERT(ip->i_d.di_nextents > 0 && ip->i_d.di_nextents <= 2); - - /* - * Lock the inode, fix the size, and join it to the transaction. - * Hold it so in the normal path, we still have it locked for - * the second transaction. In the error paths we need it - * held so the cancel won't rele it, see below. - */ - size = (int)ip->i_d.di_size; - ip->i_d.di_size = 0; - xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); - /* - * Find the block(s) so we can inval and unmap them. - */ - done = 0; - xfs_bmap_init(&free_list, &first_block); - nmaps = ARRAY_SIZE(mval); - error = xfs_bmapi_read(ip, 0, XFS_B_TO_FSB(mp, size), - mval, &nmaps, 0); - if (error) - goto error0; - /* - * Invalidate the block(s). - */ - for (i = 0; i < nmaps; i++) { - bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, - XFS_FSB_TO_DADDR(mp, mval[i].br_startblock), - XFS_FSB_TO_BB(mp, mval[i].br_blockcount), 0); - if (!bp) { - error = ENOMEM; - goto error1; - } - xfs_trans_binval(tp, bp); - } - /* - * Unmap the dead block(s) to the free_list. - */ - if ((error = xfs_bunmapi(tp, ip, 0, size, XFS_BMAPI_METADATA, nmaps, - &first_block, &free_list, &done))) - goto error1; - ASSERT(done); - /* - * Commit the first transaction. This logs the EFI and the inode. - */ - if ((error = xfs_bmap_finish(&tp, &free_list, &committed))) - goto error1; - /* - * The transaction must have been committed, since there were - * actually extents freed by xfs_bunmapi. See xfs_bmap_finish. - * The new tp has the extent freeing and EFDs. - */ - ASSERT(committed); - /* - * The first xact was committed, so add the inode to the new one. - * Mark it dirty so it will be logged and moved forward in the log as - * part of every commit. - */ - xfs_trans_ijoin(tp, ip, 0); - xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); - /* - * Get a new, empty transaction to return to our caller. - */ - ntp = xfs_trans_dup(tp); - /* - * Commit the transaction containing extent freeing and EFDs. - * If we get an error on the commit here or on the reserve below, - * we need to unlock the inode since the new transaction doesn't - * have the inode attached. - */ - error = xfs_trans_commit(tp, 0); - tp = ntp; - if (error) { - ASSERT(XFS_FORCED_SHUTDOWN(mp)); - goto error0; - } - /* - * transaction commit worked ok so we can drop the extra ticket - * reference that we gained in xfs_trans_dup() - */ - xfs_log_ticket_put(tp->t_ticket); - - /* - * Remove the memory for extent descriptions (just bookkeeping). - */ - if (ip->i_df.if_bytes) - xfs_idata_realloc(ip, -ip->i_df.if_bytes, XFS_DATA_FORK); - ASSERT(ip->i_df.if_bytes == 0); - /* - * Put an itruncate log reservation in the new transaction - * for our caller. - */ - if ((error = xfs_trans_reserve(tp, 0, XFS_ITRUNCATE_LOG_RES(mp), 0, - XFS_TRANS_PERM_LOG_RES, XFS_ITRUNCATE_LOG_COUNT))) { - ASSERT(XFS_FORCED_SHUTDOWN(mp)); - goto error0; - } - - xfs_trans_ijoin(tp, ip, 0); - *tpp = tp; - return 0; - - error1: - xfs_bmap_cancel(&free_list); - error0: - return error; -} - int xfs_release( xfs_inode_t *ip) @@ -1353,247 +1122,6 @@ xfs_link( } int -xfs_symlink( - xfs_inode_t *dp, - struct xfs_name *link_name, - const char *target_path, - umode_t mode, - xfs_inode_t **ipp) -{ - xfs_mount_t *mp = dp->i_mount; - xfs_trans_t *tp; - xfs_inode_t *ip; - int error; - int pathlen; - xfs_bmap_free_t free_list; - xfs_fsblock_t first_block; - bool unlock_dp_on_error = false; - uint cancel_flags; - int committed; - xfs_fileoff_t first_fsb; - xfs_filblks_t fs_blocks; - int nmaps; - xfs_bmbt_irec_t mval[SYMLINK_MAPS]; - xfs_daddr_t d; - const char *cur_chunk; - int byte_cnt; - int n; - xfs_buf_t *bp; - prid_t prid; - struct xfs_dquot *udqp, *gdqp; - uint resblks; - - *ipp = NULL; - error = 0; - ip = NULL; - tp = NULL; - - trace_xfs_symlink(dp, link_name); - - if (XFS_FORCED_SHUTDOWN(mp)) - return XFS_ERROR(EIO); - - /* - * Check component lengths of the target path name. - */ - pathlen = strlen(target_path); - if (pathlen >= MAXPATHLEN) /* total string too long */ - return XFS_ERROR(ENAMETOOLONG); - - udqp = gdqp = NULL; - if (dp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) - prid = xfs_get_projid(dp); - else - prid = XFS_PROJID_DEFAULT; - - /* - * Make sure that we have allocated dquot(s) on disk. - */ - error = xfs_qm_vop_dqalloc(dp, current_fsuid(), current_fsgid(), prid, - XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT, &udqp, &gdqp); - if (error) - goto std_return; - - tp = xfs_trans_alloc(mp, XFS_TRANS_SYMLINK); - cancel_flags = XFS_TRANS_RELEASE_LOG_RES; - /* - * The symlink will fit into the inode data fork? - * There can't be any attributes so we get the whole variable part. - */ - if (pathlen <= XFS_LITINO(mp, dp->i_d.di_version)) - fs_blocks = 0; - else - fs_blocks = XFS_B_TO_FSB(mp, pathlen); - resblks = XFS_SYMLINK_SPACE_RES(mp, link_name->len, fs_blocks); - error = xfs_trans_reserve(tp, resblks, XFS_SYMLINK_LOG_RES(mp), 0, - XFS_TRANS_PERM_LOG_RES, XFS_SYMLINK_LOG_COUNT); - if (error == ENOSPC && fs_blocks == 0) { - resblks = 0; - error = xfs_trans_reserve(tp, 0, XFS_SYMLINK_LOG_RES(mp), 0, - XFS_TRANS_PERM_LOG_RES, XFS_SYMLINK_LOG_COUNT); - } - if (error) { - cancel_flags = 0; - goto error_return; - } - - xfs_ilock(dp, XFS_ILOCK_EXCL | XFS_ILOCK_PARENT); - unlock_dp_on_error = true; - - /* - * Check whether the directory allows new symlinks or not. - */ - if (dp->i_d.di_flags & XFS_DIFLAG_NOSYMLINKS) { - error = XFS_ERROR(EPERM); - goto error_return; - } - - /* - * Reserve disk quota : blocks and inode. - */ - error = xfs_trans_reserve_quota(tp, mp, udqp, gdqp, resblks, 1, 0); - if (error) - goto error_return; - - /* - * Check for ability to enter directory entry, if no space reserved. - */ - error = xfs_dir_canenter(tp, dp, link_name, resblks); - if (error) - goto error_return; - /* - * Initialize the bmap freelist prior to calling either - * bmapi or the directory create code. - */ - xfs_bmap_init(&free_list, &first_block); - - /* - * Allocate an inode for the symlink. - */ - error = xfs_dir_ialloc(&tp, dp, S_IFLNK | (mode & ~S_IFMT), 1, 0, - prid, resblks > 0, &ip, NULL); - if (error) { - if (error == ENOSPC) - goto error_return; - goto error1; - } - - /* - * An error after we've joined dp to the transaction will result in the - * transaction cancel unlocking dp so don't do it explicitly in the - * error path. - */ - xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL); - unlock_dp_on_error = false; - - /* - * Also attach the dquot(s) to it, if applicable. - */ - xfs_qm_vop_create_dqattach(tp, ip, udqp, gdqp); - - if (resblks) - resblks -= XFS_IALLOC_SPACE_RES(mp); - /* - * If the symlink will fit into the inode, write it inline. - */ - if (pathlen <= XFS_IFORK_DSIZE(ip)) { - xfs_idata_realloc(ip, pathlen, XFS_DATA_FORK); - memcpy(ip->i_df.if_u1.if_data, target_path, pathlen); - ip->i_d.di_size = pathlen; - - /* - * The inode was initially created in extent format. - */ - ip->i_df.if_flags &= ~(XFS_IFEXTENTS | XFS_IFBROOT); - ip->i_df.if_flags |= XFS_IFINLINE; - - ip->i_d.di_format = XFS_DINODE_FMT_LOCAL; - xfs_trans_log_inode(tp, ip, XFS_ILOG_DDATA | XFS_ILOG_CORE); - - } else { - first_fsb = 0; - nmaps = SYMLINK_MAPS; - - error = xfs_bmapi_write(tp, ip, first_fsb, fs_blocks, - XFS_BMAPI_METADATA, &first_block, resblks, - mval, &nmaps, &free_list); - if (error) - goto error2; - - if (resblks) - resblks -= fs_blocks; - ip->i_d.di_size = pathlen; - xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); - - cur_chunk = target_path; - for (n = 0; n < nmaps; n++) { - d = XFS_FSB_TO_DADDR(mp, mval[n].br_startblock); - byte_cnt = XFS_FSB_TO_B(mp, mval[n].br_blockcount); - bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, d, - BTOBB(byte_cnt), 0); - if (!bp) { - error = ENOMEM; - goto error2; - } - if (pathlen < byte_cnt) { - byte_cnt = pathlen; - } - pathlen -= byte_cnt; - - memcpy(bp->b_addr, cur_chunk, byte_cnt); - cur_chunk += byte_cnt; - - xfs_trans_log_buf(tp, bp, 0, byte_cnt - 1); - } - } - - /* - * Create the directory entry for the symlink. - */ - error = xfs_dir_createname(tp, dp, link_name, ip->i_ino, - &first_block, &free_list, resblks); - if (error) - goto error2; - xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG); - xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE); - - /* - * If this is a synchronous mount, make sure that the - * symlink transaction goes to disk before returning to - * the user. - */ - if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC)) { - xfs_trans_set_sync(tp); - } - - error = xfs_bmap_finish(&tp, &free_list, &committed); - if (error) { - goto error2; - } - error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES); - xfs_qm_dqrele(udqp); - xfs_qm_dqrele(gdqp); - - *ipp = ip; - return 0; - - error2: - IRELE(ip); - error1: - xfs_bmap_cancel(&free_list); - cancel_flags |= XFS_TRANS_ABORT; - error_return: - xfs_trans_cancel(tp, cancel_flags); - xfs_qm_dqrele(udqp); - xfs_qm_dqrele(gdqp); - - if (unlock_dp_on_error) - xfs_iunlock(dp, XFS_ILOCK_EXCL); - std_return: - return error; -} - -int xfs_set_dmattrs( xfs_inode_t *ip, u_int evmask, -- 1.7.10 _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs