diff options
Diffstat (limited to 'fs/xfs/libxfs/xfs_dir2_data.c')
| -rw-r--r-- | fs/xfs/libxfs/xfs_dir2_data.c | 1169 |
1 files changed, 1169 insertions, 0 deletions
diff --git a/fs/xfs/libxfs/xfs_dir2_data.c b/fs/xfs/libxfs/xfs_dir2_data.c new file mode 100644 index 000000000..01162c62e --- /dev/null +++ b/fs/xfs/libxfs/xfs_dir2_data.c @@ -0,0 +1,1169 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc. + * Copyright (c) 2013 Red Hat, Inc. + * All Rights Reserved. + */ +#include "xfs.h" +#include "xfs_fs.h" +#include "xfs_format.h" +#include "xfs_log_format.h" +#include "xfs_trans_resv.h" +#include "xfs_mount.h" +#include "xfs_da_format.h" +#include "xfs_da_btree.h" +#include "xfs_inode.h" +#include "xfs_dir2.h" +#include "xfs_dir2_priv.h" +#include "xfs_error.h" +#include "xfs_trans.h" +#include "xfs_buf_item.h" +#include "xfs_cksum.h" +#include "xfs_log.h" + +static xfs_failaddr_t xfs_dir2_data_freefind_verify( + struct xfs_dir2_data_hdr *hdr, struct xfs_dir2_data_free *bf, + struct xfs_dir2_data_unused *dup, + struct xfs_dir2_data_free **bf_ent); + +/* + * Check the consistency of the data block. + * The input can also be a block-format directory. + * Return NULL if the buffer is good, otherwise the address of the error. + */ +xfs_failaddr_t +__xfs_dir3_data_check( + struct xfs_inode *dp, /* incore inode pointer */ + struct xfs_buf *bp) /* data block's buffer */ +{ + xfs_dir2_dataptr_t addr; /* addr for leaf lookup */ + xfs_dir2_data_free_t *bf; /* bestfree table */ + xfs_dir2_block_tail_t *btp=NULL; /* block tail */ + int count; /* count of entries found */ + xfs_dir2_data_hdr_t *hdr; /* data block header */ + xfs_dir2_data_entry_t *dep; /* data entry */ + xfs_dir2_data_free_t *dfp; /* bestfree entry */ + xfs_dir2_data_unused_t *dup; /* unused entry */ + char *endp; /* end of useful data */ + int freeseen; /* mask of bestfrees seen */ + xfs_dahash_t hash; /* hash of current name */ + int i; /* leaf index */ + int lastfree; /* last entry was unused */ + xfs_dir2_leaf_entry_t *lep=NULL; /* block leaf entries */ + xfs_mount_t *mp; /* filesystem mount point */ + char *p; /* current data position */ + int stale; /* count of stale leaves */ + struct xfs_name name; + const struct xfs_dir_ops *ops; + struct xfs_da_geometry *geo; + + mp = bp->b_target->bt_mount; + geo = mp->m_dir_geo; + + /* + * We can be passed a null dp here from a verifier, so we need to go the + * hard way to get them. + */ + ops = xfs_dir_get_ops(mp, dp); + + /* + * If this isn't a directory, or we don't get handed the dir ops, + * something is seriously wrong. Bail out. + */ + if ((dp && !S_ISDIR(VFS_I(dp)->i_mode)) || + ops != xfs_dir_get_ops(mp, NULL)) + return __this_address; + + hdr = bp->b_addr; + p = (char *)ops->data_entry_p(hdr); + + switch (hdr->magic) { + case cpu_to_be32(XFS_DIR3_BLOCK_MAGIC): + case cpu_to_be32(XFS_DIR2_BLOCK_MAGIC): + btp = xfs_dir2_block_tail_p(geo, hdr); + lep = xfs_dir2_block_leaf_p(btp); + + /* + * The number of leaf entries is limited by the size of the + * block and the amount of space used by the data entries. + * We don't know how much space is used by the data entries yet, + * so just ensure that the count falls somewhere inside the + * block right now. + */ + if (be32_to_cpu(btp->count) >= + ((char *)btp - p) / sizeof(struct xfs_dir2_leaf_entry)) + return __this_address; + break; + case cpu_to_be32(XFS_DIR3_DATA_MAGIC): + case cpu_to_be32(XFS_DIR2_DATA_MAGIC): + break; + default: + return __this_address; + } + endp = xfs_dir3_data_endp(geo, hdr); + if (!endp) + return __this_address; + + /* + * Account for zero bestfree entries. + */ + bf = ops->data_bestfree_p(hdr); + count = lastfree = freeseen = 0; + if (!bf[0].length) { + if (bf[0].offset) + return __this_address; + freeseen |= 1 << 0; + } + if (!bf[1].length) { + if (bf[1].offset) + return __this_address; + freeseen |= 1 << 1; + } + if (!bf[2].length) { + if (bf[2].offset) + return __this_address; + freeseen |= 1 << 2; + } + + if (be16_to_cpu(bf[0].length) < be16_to_cpu(bf[1].length)) + return __this_address; + if (be16_to_cpu(bf[1].length) < be16_to_cpu(bf[2].length)) + return __this_address; + /* + * Loop over the data/unused entries. + */ + while (p < endp) { + dup = (xfs_dir2_data_unused_t *)p; + /* + * If it's unused, look for the space in the bestfree table. + * If we find it, account for that, else make sure it + * doesn't need to be there. + */ + if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) { + xfs_failaddr_t fa; + + if (lastfree != 0) + return __this_address; + if (endp < p + be16_to_cpu(dup->length)) + return __this_address; + if (be16_to_cpu(*xfs_dir2_data_unused_tag_p(dup)) != + (char *)dup - (char *)hdr) + return __this_address; + fa = xfs_dir2_data_freefind_verify(hdr, bf, dup, &dfp); + if (fa) + return fa; + if (dfp) { + i = (int)(dfp - bf); + if ((freeseen & (1 << i)) != 0) + return __this_address; + freeseen |= 1 << i; + } else { + if (be16_to_cpu(dup->length) > + be16_to_cpu(bf[2].length)) + return __this_address; + } + p += be16_to_cpu(dup->length); + lastfree = 1; + continue; + } + /* + * It's a real entry. Validate the fields. + * If this is a block directory then make sure it's + * in the leaf section of the block. + * The linear search is crude but this is DEBUG code. + */ + dep = (xfs_dir2_data_entry_t *)p; + if (dep->namelen == 0) + return __this_address; + if (xfs_dir_ino_validate(mp, be64_to_cpu(dep->inumber))) + return __this_address; + if (endp < p + ops->data_entsize(dep->namelen)) + return __this_address; + if (be16_to_cpu(*ops->data_entry_tag_p(dep)) != + (char *)dep - (char *)hdr) + return __this_address; + if (ops->data_get_ftype(dep) >= XFS_DIR3_FT_MAX) + return __this_address; + count++; + lastfree = 0; + if (hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) || + hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)) { + addr = xfs_dir2_db_off_to_dataptr(geo, geo->datablk, + (xfs_dir2_data_aoff_t) + ((char *)dep - (char *)hdr)); + name.name = dep->name; + name.len = dep->namelen; + hash = mp->m_dirnameops->hashname(&name); + for (i = 0; i < be32_to_cpu(btp->count); i++) { + if (be32_to_cpu(lep[i].address) == addr && + be32_to_cpu(lep[i].hashval) == hash) + break; + } + if (i >= be32_to_cpu(btp->count)) + return __this_address; + } + p += ops->data_entsize(dep->namelen); + } + /* + * Need to have seen all the entries and all the bestfree slots. + */ + if (freeseen != 7) + return __this_address; + if (hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) || + hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)) { + for (i = stale = 0; i < be32_to_cpu(btp->count); i++) { + if (lep[i].address == + cpu_to_be32(XFS_DIR2_NULL_DATAPTR)) + stale++; + if (i > 0 && be32_to_cpu(lep[i].hashval) < + be32_to_cpu(lep[i - 1].hashval)) + return __this_address; + } + if (count != be32_to_cpu(btp->count) - be32_to_cpu(btp->stale)) + return __this_address; + if (stale != be32_to_cpu(btp->stale)) + return __this_address; + } + return NULL; +} + +#ifdef DEBUG +void +xfs_dir3_data_check( + struct xfs_inode *dp, + struct xfs_buf *bp) +{ + xfs_failaddr_t fa; + + fa = __xfs_dir3_data_check(dp, bp); + if (!fa) + return; + xfs_corruption_error(__func__, XFS_ERRLEVEL_LOW, dp->i_mount, + bp->b_addr, BBTOB(bp->b_length), __FILE__, __LINE__, + fa); + ASSERT(0); +} +#endif + +static xfs_failaddr_t +xfs_dir3_data_verify( + struct xfs_buf *bp) +{ + struct xfs_mount *mp = bp->b_target->bt_mount; + struct xfs_dir3_blk_hdr *hdr3 = bp->b_addr; + + if (xfs_sb_version_hascrc(&mp->m_sb)) { + if (hdr3->magic != cpu_to_be32(XFS_DIR3_DATA_MAGIC)) + return __this_address; + if (!uuid_equal(&hdr3->uuid, &mp->m_sb.sb_meta_uuid)) + return __this_address; + if (be64_to_cpu(hdr3->blkno) != bp->b_bn) + return __this_address; + if (!xfs_log_check_lsn(mp, be64_to_cpu(hdr3->lsn))) + return __this_address; + } else { + if (hdr3->magic != cpu_to_be32(XFS_DIR2_DATA_MAGIC)) + return __this_address; + } + return __xfs_dir3_data_check(NULL, bp); +} + +/* + * Readahead of the first block of the directory when it is opened is completely + * oblivious to the format of the directory. Hence we can either get a block + * format buffer or a data format buffer on readahead. + */ +static void +xfs_dir3_data_reada_verify( + struct xfs_buf *bp) +{ + struct xfs_dir2_data_hdr *hdr = bp->b_addr; + + switch (hdr->magic) { + case cpu_to_be32(XFS_DIR2_BLOCK_MAGIC): + case cpu_to_be32(XFS_DIR3_BLOCK_MAGIC): + bp->b_ops = &xfs_dir3_block_buf_ops; + bp->b_ops->verify_read(bp); + return; + case cpu_to_be32(XFS_DIR2_DATA_MAGIC): + case cpu_to_be32(XFS_DIR3_DATA_MAGIC): + bp->b_ops = &xfs_dir3_data_buf_ops; + bp->b_ops->verify_read(bp); + return; + default: + xfs_verifier_error(bp, -EFSCORRUPTED, __this_address); + break; + } +} + +static void +xfs_dir3_data_read_verify( + struct xfs_buf *bp) +{ + struct xfs_mount *mp = bp->b_target->bt_mount; + xfs_failaddr_t fa; + + if (xfs_sb_version_hascrc(&mp->m_sb) && + !xfs_buf_verify_cksum(bp, XFS_DIR3_DATA_CRC_OFF)) + xfs_verifier_error(bp, -EFSBADCRC, __this_address); + else { + fa = xfs_dir3_data_verify(bp); + if (fa) + xfs_verifier_error(bp, -EFSCORRUPTED, fa); + } +} + +static void +xfs_dir3_data_write_verify( + struct xfs_buf *bp) +{ + struct xfs_mount *mp = bp->b_target->bt_mount; + struct xfs_buf_log_item *bip = bp->b_log_item; + struct xfs_dir3_blk_hdr *hdr3 = bp->b_addr; + xfs_failaddr_t fa; + + fa = xfs_dir3_data_verify(bp); + if (fa) { + xfs_verifier_error(bp, -EFSCORRUPTED, fa); + return; + } + + if (!xfs_sb_version_hascrc(&mp->m_sb)) + return; + + if (bip) + hdr3->lsn = cpu_to_be64(bip->bli_item.li_lsn); + + xfs_buf_update_cksum(bp, XFS_DIR3_DATA_CRC_OFF); +} + +const struct xfs_buf_ops xfs_dir3_data_buf_ops = { + .name = "xfs_dir3_data", + .verify_read = xfs_dir3_data_read_verify, + .verify_write = xfs_dir3_data_write_verify, + .verify_struct = xfs_dir3_data_verify, +}; + +static const struct xfs_buf_ops xfs_dir3_data_reada_buf_ops = { + .name = "xfs_dir3_data_reada", + .verify_read = xfs_dir3_data_reada_verify, + .verify_write = xfs_dir3_data_write_verify, +}; + + +int +xfs_dir3_data_read( + struct xfs_trans *tp, + struct xfs_inode *dp, + xfs_dablk_t bno, + xfs_daddr_t mapped_bno, + struct xfs_buf **bpp) +{ + int err; + + err = xfs_da_read_buf(tp, dp, bno, mapped_bno, bpp, + XFS_DATA_FORK, &xfs_dir3_data_buf_ops); + if (!err && tp && *bpp) + xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_DIR_DATA_BUF); + return err; +} + +int +xfs_dir3_data_readahead( + struct xfs_inode *dp, + xfs_dablk_t bno, + xfs_daddr_t mapped_bno) +{ + return xfs_da_reada_buf(dp, bno, mapped_bno, + XFS_DATA_FORK, &xfs_dir3_data_reada_buf_ops); +} + +/* + * Find the bestfree entry that exactly coincides with unused directory space + * or a verifier error because the bestfree data are bad. + */ +static xfs_failaddr_t +xfs_dir2_data_freefind_verify( + struct xfs_dir2_data_hdr *hdr, + struct xfs_dir2_data_free *bf, + struct xfs_dir2_data_unused *dup, + struct xfs_dir2_data_free **bf_ent) +{ + struct xfs_dir2_data_free *dfp; + xfs_dir2_data_aoff_t off; + bool matched = false; + bool seenzero = false; + + *bf_ent = NULL; + off = (xfs_dir2_data_aoff_t)((char *)dup - (char *)hdr); + + /* + * Validate some consistency in the bestfree table. + * Check order, non-overlapping entries, and if we find the + * one we're looking for it has to be exact. + */ + for (dfp = &bf[0]; dfp < &bf[XFS_DIR2_DATA_FD_COUNT]; dfp++) { + if (!dfp->offset) { + if (dfp->length) + return __this_address; + seenzero = true; + continue; + } + if (seenzero) + return __this_address; + if (be16_to_cpu(dfp->offset) == off) { + matched = true; + if (dfp->length != dup->length) + return __this_address; + } else if (be16_to_cpu(dfp->offset) > off) { + if (off + be16_to_cpu(dup->length) > + be16_to_cpu(dfp->offset)) + return __this_address; + } else { + if (be16_to_cpu(dfp->offset) + + be16_to_cpu(dfp->length) > off) + return __this_address; + } + if (!matched && + be16_to_cpu(dfp->length) < be16_to_cpu(dup->length)) + return __this_address; + if (dfp > &bf[0] && + be16_to_cpu(dfp[-1].length) < be16_to_cpu(dfp[0].length)) + return __this_address; + } + + /* Looks ok so far; now try to match up with a bestfree entry. */ + *bf_ent = xfs_dir2_data_freefind(hdr, bf, dup); + return NULL; +} + +/* + * Given a data block and an unused entry from that block, + * return the bestfree entry if any that corresponds to it. + */ +xfs_dir2_data_free_t * +xfs_dir2_data_freefind( + struct xfs_dir2_data_hdr *hdr, /* data block header */ + struct xfs_dir2_data_free *bf, /* bestfree table pointer */ + struct xfs_dir2_data_unused *dup) /* unused space */ +{ + xfs_dir2_data_free_t *dfp; /* bestfree entry */ + xfs_dir2_data_aoff_t off; /* offset value needed */ + + off = (xfs_dir2_data_aoff_t)((char *)dup - (char *)hdr); + + /* + * If this is smaller than the smallest bestfree entry, + * it can't be there since they're sorted. + */ + if (be16_to_cpu(dup->length) < + be16_to_cpu(bf[XFS_DIR2_DATA_FD_COUNT - 1].length)) + return NULL; + /* + * Look at the three bestfree entries for our guy. + */ + for (dfp = &bf[0]; dfp < &bf[XFS_DIR2_DATA_FD_COUNT]; dfp++) { + if (!dfp->offset) + return NULL; + if (be16_to_cpu(dfp->offset) == off) + return dfp; + } + /* + * Didn't find it. This only happens if there are duplicate lengths. + */ + return NULL; +} + +/* + * Insert an unused-space entry into the bestfree table. + */ +xfs_dir2_data_free_t * /* entry inserted */ +xfs_dir2_data_freeinsert( + struct xfs_dir2_data_hdr *hdr, /* data block pointer */ + struct xfs_dir2_data_free *dfp, /* bestfree table pointer */ + struct xfs_dir2_data_unused *dup, /* unused space */ + int *loghead) /* log the data header (out) */ +{ + xfs_dir2_data_free_t new; /* new bestfree entry */ + + ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) || + hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) || + hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) || + hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)); + + new.length = dup->length; + new.offset = cpu_to_be16((char *)dup - (char *)hdr); + + /* + * Insert at position 0, 1, or 2; or not at all. + */ + if (be16_to_cpu(new.length) > be16_to_cpu(dfp[0].length)) { + dfp[2] = dfp[1]; + dfp[1] = dfp[0]; + dfp[0] = new; + *loghead = 1; + return &dfp[0]; + } + if (be16_to_cpu(new.length) > be16_to_cpu(dfp[1].length)) { + dfp[2] = dfp[1]; + dfp[1] = new; + *loghead = 1; + return &dfp[1]; + } + if (be16_to_cpu(new.length) > be16_to_cpu(dfp[2].length)) { + dfp[2] = new; + *loghead = 1; + return &dfp[2]; + } + return NULL; +} + +/* + * Remove a bestfree entry from the table. + */ +STATIC void +xfs_dir2_data_freeremove( + struct xfs_dir2_data_hdr *hdr, /* data block header */ + struct xfs_dir2_data_free *bf, /* bestfree table pointer */ + struct xfs_dir2_data_free *dfp, /* bestfree entry pointer */ + int *loghead) /* out: log data header */ +{ + + ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) || + hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) || + hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) || + hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)); + + /* + * It's the first entry, slide the next 2 up. + */ + if (dfp == &bf[0]) { + bf[0] = bf[1]; + bf[1] = bf[2]; + } + /* + * It's the second entry, slide the 3rd entry up. + */ + else if (dfp == &bf[1]) + bf[1] = bf[2]; + /* + * Must be the last entry. + */ + else + ASSERT(dfp == &bf[2]); + /* + * Clear the 3rd entry, must be zero now. + */ + bf[2].length = 0; + bf[2].offset = 0; + *loghead = 1; +} + +/* + * Given a data block, reconstruct its bestfree map. + */ +void +xfs_dir2_data_freescan_int( + struct xfs_da_geometry *geo, + const struct xfs_dir_ops *ops, + struct xfs_dir2_data_hdr *hdr, + int *loghead) +{ + xfs_dir2_data_entry_t *dep; /* active data entry */ + xfs_dir2_data_unused_t *dup; /* unused data entry */ + struct xfs_dir2_data_free *bf; + char *endp; /* end of block's data */ + char *p; /* current entry pointer */ + + ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) || + hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) || + hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) || + hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)); + + /* + * Start by clearing the table. + */ + bf = ops->data_bestfree_p(hdr); + memset(bf, 0, sizeof(*bf) * XFS_DIR2_DATA_FD_COUNT); + *loghead = 1; + /* + * Set up pointers. + */ + p = (char *)ops->data_entry_p(hdr); + endp = xfs_dir3_data_endp(geo, hdr); + /* + * Loop over the block's entries. + */ + while (p < endp) { + dup = (xfs_dir2_data_unused_t *)p; + /* + * If it's a free entry, insert it. + */ + if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) { + ASSERT((char *)dup - (char *)hdr == + be16_to_cpu(*xfs_dir2_data_unused_tag_p(dup))); + xfs_dir2_data_freeinsert(hdr, bf, dup, loghead); + p += be16_to_cpu(dup->length); + } + /* + * For active entries, check their tags and skip them. + */ + else { + dep = (xfs_dir2_data_entry_t *)p; + ASSERT((char *)dep - (char *)hdr == + be16_to_cpu(*ops->data_entry_tag_p(dep))); + p += ops->data_entsize(dep->namelen); + } + } +} + +void +xfs_dir2_data_freescan( + struct xfs_inode *dp, + struct xfs_dir2_data_hdr *hdr, + int *loghead) +{ + return xfs_dir2_data_freescan_int(dp->i_mount->m_dir_geo, dp->d_ops, + hdr, loghead); +} + +/* + * Initialize a data block at the given block number in the directory. + * Give back the buffer for the created block. + */ +int /* error */ +xfs_dir3_data_init( + xfs_da_args_t *args, /* directory operation args */ + xfs_dir2_db_t blkno, /* logical dir block number */ + struct xfs_buf **bpp) /* output block buffer */ +{ + struct xfs_buf *bp; /* block buffer */ + xfs_dir2_data_hdr_t *hdr; /* data block header */ + xfs_inode_t *dp; /* incore directory inode */ + xfs_dir2_data_unused_t *dup; /* unused entry pointer */ + struct xfs_dir2_data_free *bf; + int error; /* error return value */ + int i; /* bestfree index */ + xfs_mount_t *mp; /* filesystem mount point */ + xfs_trans_t *tp; /* transaction pointer */ + int t; /* temp */ + + dp = args->dp; + mp = dp->i_mount; + tp = args->trans; + /* + * Get the buffer set up for the block. + */ + error = xfs_da_get_buf(tp, dp, xfs_dir2_db_to_da(args->geo, blkno), + -1, &bp, XFS_DATA_FORK); + if (error) + return error; + bp->b_ops = &xfs_dir3_data_buf_ops; + xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DIR_DATA_BUF); + + /* + * Initialize the header. + */ + hdr = bp->b_addr; + if (xfs_sb_version_hascrc(&mp->m_sb)) { + struct xfs_dir3_blk_hdr *hdr3 = bp->b_addr; + + memset(hdr3, 0, sizeof(*hdr3)); + hdr3->magic = cpu_to_be32(XFS_DIR3_DATA_MAGIC); + hdr3->blkno = cpu_to_be64(bp->b_bn); + hdr3->owner = cpu_to_be64(dp->i_ino); + uuid_copy(&hdr3->uuid, &mp->m_sb.sb_meta_uuid); + + } else + hdr->magic = cpu_to_be32(XFS_DIR2_DATA_MAGIC); + + bf = dp->d_ops->data_bestfree_p(hdr); + bf[0].offset = cpu_to_be16(dp->d_ops->data_entry_offset); + for (i = 1; i < XFS_DIR2_DATA_FD_COUNT; i++) { + bf[i].length = 0; + bf[i].offset = 0; + } + + /* + * Set up an unused entry for the block's body. + */ + dup = dp->d_ops->data_unused_p(hdr); + dup->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG); + + t = args->geo->blksize - (uint)dp->d_ops->data_entry_offset; + bf[0].length = cpu_to_be16(t); + dup->length = cpu_to_be16(t); + *xfs_dir2_data_unused_tag_p(dup) = cpu_to_be16((char *)dup - (char *)hdr); + /* + * Log it and return it. + */ + xfs_dir2_data_log_header(args, bp); + xfs_dir2_data_log_unused(args, bp, dup); + *bpp = bp; + return 0; +} + +/* + * Log an active data entry from the block. + */ +void +xfs_dir2_data_log_entry( + struct xfs_da_args *args, + struct xfs_buf *bp, + xfs_dir2_data_entry_t *dep) /* data entry pointer */ +{ + struct xfs_dir2_data_hdr *hdr = bp->b_addr; + + ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) || + hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) || + hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) || + hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)); + + xfs_trans_log_buf(args->trans, bp, (uint)((char *)dep - (char *)hdr), + (uint)((char *)(args->dp->d_ops->data_entry_tag_p(dep) + 1) - + (char *)hdr - 1)); +} + +/* + * Log a data block header. + */ +void +xfs_dir2_data_log_header( + struct xfs_da_args *args, + struct xfs_buf *bp) +{ +#ifdef DEBUG + struct xfs_dir2_data_hdr *hdr = bp->b_addr; + + ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) || + hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) || + hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) || + hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)); +#endif + + xfs_trans_log_buf(args->trans, bp, 0, + args->dp->d_ops->data_entry_offset - 1); +} + +/* + * Log a data unused entry. + */ +void +xfs_dir2_data_log_unused( + struct xfs_da_args *args, + struct xfs_buf *bp, + xfs_dir2_data_unused_t *dup) /* data unused pointer */ +{ + xfs_dir2_data_hdr_t *hdr = bp->b_addr; + + ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) || + hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) || + hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) || + hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)); + + /* + * Log the first part of the unused entry. + */ + xfs_trans_log_buf(args->trans, bp, (uint)((char *)dup - (char *)hdr), + (uint)((char *)&dup->length + sizeof(dup->length) - + 1 - (char *)hdr)); + /* + * Log the end (tag) of the unused entry. + */ + xfs_trans_log_buf(args->trans, bp, + (uint)((char *)xfs_dir2_data_unused_tag_p(dup) - (char *)hdr), + (uint)((char *)xfs_dir2_data_unused_tag_p(dup) - (char *)hdr + + sizeof(xfs_dir2_data_off_t) - 1)); +} + +/* + * Make a byte range in the data block unused. + * Its current contents are unimportant. + */ +void +xfs_dir2_data_make_free( + struct xfs_da_args *args, + struct xfs_buf *bp, + xfs_dir2_data_aoff_t offset, /* starting byte offset */ + xfs_dir2_data_aoff_t len, /* length in bytes */ + int *needlogp, /* out: log header */ + int *needscanp) /* out: regen bestfree */ +{ + xfs_dir2_data_hdr_t *hdr; /* data block pointer */ + xfs_dir2_data_free_t *dfp; /* bestfree pointer */ + char *endptr; /* end of data area */ + int needscan; /* need to regen bestfree */ + xfs_dir2_data_unused_t *newdup; /* new unused entry */ + xfs_dir2_data_unused_t *postdup; /* unused entry after us */ + xfs_dir2_data_unused_t *prevdup; /* unused entry before us */ + struct xfs_dir2_data_free *bf; + + hdr = bp->b_addr; + + /* + * Figure out where the end of the data area is. + */ + endptr = xfs_dir3_data_endp(args->geo, hdr); + ASSERT(endptr != NULL); + + /* + * If this isn't the start of the block, then back up to + * the previous entry and see if it's free. + */ + if (offset > args->dp->d_ops->data_entry_offset) { + __be16 *tagp; /* tag just before us */ + + tagp = (__be16 *)((char *)hdr + offset) - 1; + prevdup = (xfs_dir2_data_unused_t *)((char *)hdr + be16_to_cpu(*tagp)); + if (be16_to_cpu(prevdup->freetag) != XFS_DIR2_DATA_FREE_TAG) + prevdup = NULL; + } else + prevdup = NULL; + /* + * If this isn't the end of the block, see if the entry after + * us is free. + */ + if ((char *)hdr + offset + len < endptr) { + postdup = + (xfs_dir2_data_unused_t *)((char *)hdr + offset + len); + if (be16_to_cpu(postdup->freetag) != XFS_DIR2_DATA_FREE_TAG) + postdup = NULL; + } else + postdup = NULL; + ASSERT(*needscanp == 0); + needscan = 0; + /* + * Previous and following entries are both free, + * merge everything into a single free entry. + */ + bf = args->dp->d_ops->data_bestfree_p(hdr); + if (prevdup && postdup) { + xfs_dir2_data_free_t *dfp2; /* another bestfree pointer */ + + /* + * See if prevdup and/or postdup are in bestfree table. + */ + dfp = xfs_dir2_data_freefind(hdr, bf, prevdup); + dfp2 = xfs_dir2_data_freefind(hdr, bf, postdup); + /* + * We need a rescan unless there are exactly 2 free entries + * namely our two. Then we know what's happening, otherwise + * since the third bestfree is there, there might be more + * entries. + */ + needscan = (bf[2].length != 0); + /* + * Fix up the new big freespace. + */ + be16_add_cpu(&prevdup->length, len + be16_to_cpu(postdup->length)); + *xfs_dir2_data_unused_tag_p(prevdup) = + cpu_to_be16((char *)prevdup - (char *)hdr); + xfs_dir2_data_log_unused(args, bp, prevdup); + if (!needscan) { + /* + * Has to be the case that entries 0 and 1 are + * dfp and dfp2 (don't know which is which), and + * entry 2 is empty. + * Remove entry 1 first then entry 0. + */ + ASSERT(dfp && dfp2); + if (dfp == &bf[1]) { + dfp = &bf[0]; + ASSERT(dfp2 == dfp); + dfp2 = &bf[1]; + } + xfs_dir2_data_freeremove(hdr, bf, dfp2, needlogp); + xfs_dir2_data_freeremove(hdr, bf, dfp, needlogp); + /* + * Now insert the new entry. + */ + dfp = xfs_dir2_data_freeinsert(hdr, bf, prevdup, + needlogp); + ASSERT(dfp == &bf[0]); + ASSERT(dfp->length == prevdup->length); + ASSERT(!dfp[1].length); + ASSERT(!dfp[2].length); + } + } + /* + * The entry before us is free, merge with it. + */ + else if (prevdup) { + dfp = xfs_dir2_data_freefind(hdr, bf, prevdup); + be16_add_cpu(&prevdup->length, len); + *xfs_dir2_data_unused_tag_p(prevdup) = + cpu_to_be16((char *)prevdup - (char *)hdr); + xfs_dir2_data_log_unused(args, bp, prevdup); + /* + * If the previous entry was in the table, the new entry + * is longer, so it will be in the table too. Remove + * the old one and add the new one. + */ + if (dfp) { + xfs_dir2_data_freeremove(hdr, bf, dfp, needlogp); + xfs_dir2_data_freeinsert(hdr, bf, prevdup, needlogp); + } + /* + * Otherwise we need a scan if the new entry is big enough. + */ + else { + needscan = be16_to_cpu(prevdup->length) > + be16_to_cpu(bf[2].length); + } + } + /* + * The following entry is free, merge with it. + */ + else if (postdup) { + dfp = xfs_dir2_data_freefind(hdr, bf, postdup); + newdup = (xfs_dir2_data_unused_t *)((char *)hdr + offset); + newdup->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG); + newdup->length = cpu_to_be16(len + be16_to_cpu(postdup->length)); + *xfs_dir2_data_unused_tag_p(newdup) = + cpu_to_be16((char *)newdup - (char *)hdr); + xfs_dir2_data_log_unused(args, bp, newdup); + /* + * If the following entry was in the table, the new entry + * is longer, so it will be in the table too. Remove + * the old one and add the new one. + */ + if (dfp) { + xfs_dir2_data_freeremove(hdr, bf, dfp, needlogp); + xfs_dir2_data_freeinsert(hdr, bf, newdup, needlogp); + } + /* + * Otherwise we need a scan if the new entry is big enough. + */ + else { + needscan = be16_to_cpu(newdup->length) > + be16_to_cpu(bf[2].length); + } + } + /* + * Neither neighbor is free. Make a new entry. + */ + else { + newdup = (xfs_dir2_data_unused_t *)((char *)hdr + offset); + newdup->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG); + newdup->length = cpu_to_be16(len); + *xfs_dir2_data_unused_tag_p(newdup) = + cpu_to_be16((char *)newdup - (char *)hdr); + xfs_dir2_data_log_unused(args, bp, newdup); + xfs_dir2_data_freeinsert(hdr, bf, newdup, needlogp); + } + *needscanp = needscan; +} + +/* Check our free data for obvious signs of corruption. */ +static inline xfs_failaddr_t +xfs_dir2_data_check_free( + struct xfs_dir2_data_hdr *hdr, + struct xfs_dir2_data_unused *dup, + xfs_dir2_data_aoff_t offset, + xfs_dir2_data_aoff_t len) +{ + if (hdr->magic != cpu_to_be32(XFS_DIR2_DATA_MAGIC) && + hdr->magic != cpu_to_be32(XFS_DIR3_DATA_MAGIC) && + hdr->magic != cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) && + hdr->magic != cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)) + return __this_address; + if (be16_to_cpu(dup->freetag) != XFS_DIR2_DATA_FREE_TAG) + return __this_address; + if (offset < (char *)dup - (char *)hdr) + return __this_address; + if (offset + len > (char *)dup + be16_to_cpu(dup->length) - (char *)hdr) + return __this_address; + if ((char *)dup - (char *)hdr != + be16_to_cpu(*xfs_dir2_data_unused_tag_p(dup))) + return __this_address; + return NULL; +} + +/* Sanity-check a new bestfree entry. */ +static inline xfs_failaddr_t +xfs_dir2_data_check_new_free( + struct xfs_dir2_data_hdr *hdr, + struct xfs_dir2_data_free *dfp, + struct xfs_dir2_data_unused *newdup) +{ + if (dfp == NULL) + return __this_address; + if (dfp->length != newdup->length) + return __this_address; + if (be16_to_cpu(dfp->offset) != (char *)newdup - (char *)hdr) + return __this_address; + return NULL; +} + +/* + * Take a byte range out of an existing unused space and make it un-free. + */ +int +xfs_dir2_data_use_free( + struct xfs_da_args *args, + struct xfs_buf *bp, + xfs_dir2_data_unused_t *dup, /* unused entry */ + xfs_dir2_data_aoff_t offset, /* starting offset to use */ + xfs_dir2_data_aoff_t len, /* length to use */ + int *needlogp, /* out: need to log header */ + int *needscanp) /* out: need regen bestfree */ +{ + xfs_dir2_data_hdr_t *hdr; /* data block header */ + xfs_dir2_data_free_t *dfp; /* bestfree pointer */ + xfs_dir2_data_unused_t *newdup; /* new unused entry */ + xfs_dir2_data_unused_t *newdup2; /* another new unused entry */ + struct xfs_dir2_data_free *bf; + xfs_failaddr_t fa; + int matchback; /* matches end of freespace */ + int matchfront; /* matches start of freespace */ + int needscan; /* need to regen bestfree */ + int oldlen; /* old unused entry's length */ + + hdr = bp->b_addr; + fa = xfs_dir2_data_check_free(hdr, dup, offset, len); + if (fa) + goto corrupt; + /* + * Look up the entry in the bestfree table. + */ + oldlen = be16_to_cpu(dup->length); + bf = args->dp->d_ops->data_bestfree_p(hdr); + dfp = xfs_dir2_data_freefind(hdr, bf, dup); + ASSERT(dfp || oldlen <= be16_to_cpu(bf[2].length)); + /* + * Check for alignment with front and back of the entry. + */ + matchfront = (char *)dup - (char *)hdr == offset; + matchback = (char *)dup + oldlen - (char *)hdr == offset + len; + ASSERT(*needscanp == 0); + needscan = 0; + /* + * If we matched it exactly we just need to get rid of it from + * the bestfree table. + */ + if (matchfront && matchback) { + if (dfp) { + needscan = (bf[2].offset != 0); + if (!needscan) + xfs_dir2_data_freeremove(hdr, bf, dfp, + needlogp); + } + } + /* + * We match the first part of the entry. + * Make a new entry with the remaining freespace. + */ + else if (matchfront) { + newdup = (xfs_dir2_data_unused_t *)((char *)hdr + offset + len); + newdup->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG); + newdup->length = cpu_to_be16(oldlen - len); + *xfs_dir2_data_unused_tag_p(newdup) = + cpu_to_be16((char *)newdup - (char *)hdr); + xfs_dir2_data_log_unused(args, bp, newdup); + /* + * If it was in the table, remove it and add the new one. + */ + if (dfp) { + xfs_dir2_data_freeremove(hdr, bf, dfp, needlogp); + dfp = xfs_dir2_data_freeinsert(hdr, bf, newdup, + needlogp); + fa = xfs_dir2_data_check_new_free(hdr, dfp, newdup); + if (fa) + goto corrupt; + /* + * If we got inserted at the last slot, + * that means we don't know if there was a better + * choice for the last slot, or not. Rescan. + */ + needscan = dfp == &bf[2]; + } + } + /* + * We match the last part of the entry. + * Trim the allocated space off the tail of the entry. + */ + else if (matchback) { + newdup = dup; + newdup->length = cpu_to_be16(((char *)hdr + offset) - (char *)newdup); + *xfs_dir2_data_unused_tag_p(newdup) = + cpu_to_be16((char *)newdup - (char *)hdr); + xfs_dir2_data_log_unused(args, bp, newdup); + /* + * If it was in the table, remove it and add the new one. + */ + if (dfp) { + xfs_dir2_data_freeremove(hdr, bf, dfp, needlogp); + dfp = xfs_dir2_data_freeinsert(hdr, bf, newdup, + needlogp); + fa = xfs_dir2_data_check_new_free(hdr, dfp, newdup); + if (fa) + goto corrupt; + /* + * If we got inserted at the last slot, + * that means we don't know if there was a better + * choice for the last slot, or not. Rescan. + */ + needscan = dfp == &bf[2]; + } + } + /* + * Poking out the middle of an entry. + * Make two new entries. + */ + else { + newdup = dup; + newdup->length = cpu_to_be16(((char *)hdr + offset) - (char *)newdup); + *xfs_dir2_data_unused_tag_p(newdup) = + cpu_to_be16((char *)newdup - (char *)hdr); + xfs_dir2_data_log_unused(args, bp, newdup); + newdup2 = (xfs_dir2_data_unused_t *)((char *)hdr + offset + len); + newdup2->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG); + newdup2->length = cpu_to_be16(oldlen - len - be16_to_cpu(newdup->length)); + *xfs_dir2_data_unused_tag_p(newdup2) = + cpu_to_be16((char *)newdup2 - (char *)hdr); + xfs_dir2_data_log_unused(args, bp, newdup2); + /* + * If the old entry was in the table, we need to scan + * if the 3rd entry was valid, since these entries + * are smaller than the old one. + * If we don't need to scan that means there were 1 or 2 + * entries in the table, and removing the old and adding + * the 2 new will work. + */ + if (dfp) { + needscan = (bf[2].length != 0); + if (!needscan) { + xfs_dir2_data_freeremove(hdr, bf, dfp, + needlogp); + xfs_dir2_data_freeinsert(hdr, bf, newdup, + needlogp); + xfs_dir2_data_freeinsert(hdr, bf, newdup2, + needlogp); + } + } + } + *needscanp = needscan; + return 0; +corrupt: + xfs_corruption_error(__func__, XFS_ERRLEVEL_LOW, args->dp->i_mount, + hdr, sizeof(*hdr), __FILE__, __LINE__, fa); + return -EFSCORRUPTED; +} + +/* Find the end of the entry data in a data/block format dir block. */ +void * +xfs_dir3_data_endp( + struct xfs_da_geometry *geo, + struct xfs_dir2_data_hdr *hdr) +{ + switch (hdr->magic) { + case cpu_to_be32(XFS_DIR3_BLOCK_MAGIC): + case cpu_to_be32(XFS_DIR2_BLOCK_MAGIC): + return xfs_dir2_block_leaf_p(xfs_dir2_block_tail_p(geo, hdr)); + case cpu_to_be32(XFS_DIR3_DATA_MAGIC): + case cpu_to_be32(XFS_DIR2_DATA_MAGIC): + return (char *)hdr + geo->blksize; + default: + return NULL; + } +} |