diff options
Diffstat (limited to 'fs/xfs/libxfs/xfs_inode_buf.c')
-rw-r--r-- | fs/xfs/libxfs/xfs_inode_buf.c | 773 |
1 files changed, 773 insertions, 0 deletions
diff --git a/fs/xfs/libxfs/xfs_inode_buf.c b/fs/xfs/libxfs/xfs_inode_buf.c new file mode 100644 index 000000000..758aacd81 --- /dev/null +++ b/fs/xfs/libxfs/xfs_inode_buf.c @@ -0,0 +1,773 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2000-2006 Silicon Graphics, Inc. + * All Rights Reserved. + */ +#include "xfs.h" +#include "xfs_fs.h" +#include "xfs_shared.h" +#include "xfs_format.h" +#include "xfs_log_format.h" +#include "xfs_trans_resv.h" +#include "xfs_mount.h" +#include "xfs_ag.h" +#include "xfs_inode.h" +#include "xfs_errortag.h" +#include "xfs_error.h" +#include "xfs_icache.h" +#include "xfs_trans.h" +#include "xfs_ialloc.h" +#include "xfs_dir2.h" + +#include <linux/iversion.h> + +/* + * If we are doing readahead on an inode buffer, we might be in log recovery + * reading an inode allocation buffer that hasn't yet been replayed, and hence + * has not had the inode cores stamped into it. Hence for readahead, the buffer + * may be potentially invalid. + * + * If the readahead buffer is invalid, we need to mark it with an error and + * clear the DONE status of the buffer so that a followup read will re-read it + * from disk. We don't report the error otherwise to avoid warnings during log + * recovery and we don't get unnecessary panics on debug kernels. We use EIO here + * because all we want to do is say readahead failed; there is no-one to report + * the error to, so this will distinguish it from a non-ra verifier failure. + * Changes to this readahead error behaviour also need to be reflected in + * xfs_dquot_buf_readahead_verify(). + */ +static void +xfs_inode_buf_verify( + struct xfs_buf *bp, + bool readahead) +{ + struct xfs_mount *mp = bp->b_mount; + int i; + int ni; + + /* + * Validate the magic number and version of every inode in the buffer + */ + ni = XFS_BB_TO_FSB(mp, bp->b_length) * mp->m_sb.sb_inopblock; + for (i = 0; i < ni; i++) { + struct xfs_dinode *dip; + xfs_agino_t unlinked_ino; + int di_ok; + + dip = xfs_buf_offset(bp, (i << mp->m_sb.sb_inodelog)); + unlinked_ino = be32_to_cpu(dip->di_next_unlinked); + di_ok = xfs_verify_magic16(bp, dip->di_magic) && + xfs_dinode_good_version(mp, dip->di_version) && + xfs_verify_agino_or_null(bp->b_pag, unlinked_ino); + if (unlikely(XFS_TEST_ERROR(!di_ok, mp, + XFS_ERRTAG_ITOBP_INOTOBP))) { + if (readahead) { + bp->b_flags &= ~XBF_DONE; + xfs_buf_ioerror(bp, -EIO); + return; + } + +#ifdef DEBUG + xfs_alert(mp, + "bad inode magic/vsn daddr %lld #%d (magic=%x)", + (unsigned long long)xfs_buf_daddr(bp), i, + be16_to_cpu(dip->di_magic)); +#endif + xfs_buf_verifier_error(bp, -EFSCORRUPTED, + __func__, dip, sizeof(*dip), + NULL); + return; + } + } +} + + +static void +xfs_inode_buf_read_verify( + struct xfs_buf *bp) +{ + xfs_inode_buf_verify(bp, false); +} + +static void +xfs_inode_buf_readahead_verify( + struct xfs_buf *bp) +{ + xfs_inode_buf_verify(bp, true); +} + +static void +xfs_inode_buf_write_verify( + struct xfs_buf *bp) +{ + xfs_inode_buf_verify(bp, false); +} + +const struct xfs_buf_ops xfs_inode_buf_ops = { + .name = "xfs_inode", + .magic16 = { cpu_to_be16(XFS_DINODE_MAGIC), + cpu_to_be16(XFS_DINODE_MAGIC) }, + .verify_read = xfs_inode_buf_read_verify, + .verify_write = xfs_inode_buf_write_verify, +}; + +const struct xfs_buf_ops xfs_inode_buf_ra_ops = { + .name = "xfs_inode_ra", + .magic16 = { cpu_to_be16(XFS_DINODE_MAGIC), + cpu_to_be16(XFS_DINODE_MAGIC) }, + .verify_read = xfs_inode_buf_readahead_verify, + .verify_write = xfs_inode_buf_write_verify, +}; + + +/* + * This routine is called to map an inode to the buffer containing the on-disk + * version of the inode. It returns a pointer to the buffer containing the + * on-disk inode in the bpp parameter. + */ +int +xfs_imap_to_bp( + struct xfs_mount *mp, + struct xfs_trans *tp, + struct xfs_imap *imap, + struct xfs_buf **bpp) +{ + return xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, imap->im_blkno, + imap->im_len, XBF_UNMAPPED, bpp, + &xfs_inode_buf_ops); +} + +static inline struct timespec64 xfs_inode_decode_bigtime(uint64_t ts) +{ + struct timespec64 tv; + uint32_t n; + + tv.tv_sec = xfs_bigtime_to_unix(div_u64_rem(ts, NSEC_PER_SEC, &n)); + tv.tv_nsec = n; + + return tv; +} + +/* Convert an ondisk timestamp to an incore timestamp. */ +struct timespec64 +xfs_inode_from_disk_ts( + struct xfs_dinode *dip, + const xfs_timestamp_t ts) +{ + struct timespec64 tv; + struct xfs_legacy_timestamp *lts; + + if (xfs_dinode_has_bigtime(dip)) + return xfs_inode_decode_bigtime(be64_to_cpu(ts)); + + lts = (struct xfs_legacy_timestamp *)&ts; + tv.tv_sec = (int)be32_to_cpu(lts->t_sec); + tv.tv_nsec = (int)be32_to_cpu(lts->t_nsec); + + return tv; +} + +int +xfs_inode_from_disk( + struct xfs_inode *ip, + struct xfs_dinode *from) +{ + struct inode *inode = VFS_I(ip); + int error; + xfs_failaddr_t fa; + + ASSERT(ip->i_cowfp == NULL); + + fa = xfs_dinode_verify(ip->i_mount, ip->i_ino, from); + if (fa) { + xfs_inode_verifier_error(ip, -EFSCORRUPTED, "dinode", from, + sizeof(*from), fa); + return -EFSCORRUPTED; + } + + /* + * First get the permanent information that is needed to allocate an + * inode. If the inode is unused, mode is zero and we shouldn't mess + * with the uninitialized part of it. + */ + if (!xfs_has_v3inodes(ip->i_mount)) + ip->i_flushiter = be16_to_cpu(from->di_flushiter); + inode->i_generation = be32_to_cpu(from->di_gen); + inode->i_mode = be16_to_cpu(from->di_mode); + if (!inode->i_mode) + return 0; + + /* + * Convert v1 inodes immediately to v2 inode format as this is the + * minimum inode version format we support in the rest of the code. + * They will also be unconditionally written back to disk as v2 inodes. + */ + if (unlikely(from->di_version == 1)) { + set_nlink(inode, be16_to_cpu(from->di_onlink)); + ip->i_projid = 0; + } else { + set_nlink(inode, be32_to_cpu(from->di_nlink)); + ip->i_projid = (prid_t)be16_to_cpu(from->di_projid_hi) << 16 | + be16_to_cpu(from->di_projid_lo); + } + + i_uid_write(inode, be32_to_cpu(from->di_uid)); + i_gid_write(inode, be32_to_cpu(from->di_gid)); + + /* + * Time is signed, so need to convert to signed 32 bit before + * storing in inode timestamp which may be 64 bit. Otherwise + * a time before epoch is converted to a time long after epoch + * on 64 bit systems. + */ + inode->i_atime = xfs_inode_from_disk_ts(from, from->di_atime); + inode->i_mtime = xfs_inode_from_disk_ts(from, from->di_mtime); + inode->i_ctime = xfs_inode_from_disk_ts(from, from->di_ctime); + + ip->i_disk_size = be64_to_cpu(from->di_size); + ip->i_nblocks = be64_to_cpu(from->di_nblocks); + ip->i_extsize = be32_to_cpu(from->di_extsize); + ip->i_forkoff = from->di_forkoff; + ip->i_diflags = be16_to_cpu(from->di_flags); + ip->i_next_unlinked = be32_to_cpu(from->di_next_unlinked); + + if (from->di_dmevmask || from->di_dmstate) + xfs_iflags_set(ip, XFS_IPRESERVE_DM_FIELDS); + + if (xfs_has_v3inodes(ip->i_mount)) { + inode_set_iversion_queried(inode, + be64_to_cpu(from->di_changecount)); + ip->i_crtime = xfs_inode_from_disk_ts(from, from->di_crtime); + ip->i_diflags2 = be64_to_cpu(from->di_flags2); + ip->i_cowextsize = be32_to_cpu(from->di_cowextsize); + } + + error = xfs_iformat_data_fork(ip, from); + if (error) + return error; + if (from->di_forkoff) { + error = xfs_iformat_attr_fork(ip, from); + if (error) + goto out_destroy_data_fork; + } + if (xfs_is_reflink_inode(ip)) + xfs_ifork_init_cow(ip); + return 0; + +out_destroy_data_fork: + xfs_idestroy_fork(&ip->i_df); + return error; +} + +/* Convert an incore timestamp to an ondisk timestamp. */ +static inline xfs_timestamp_t +xfs_inode_to_disk_ts( + struct xfs_inode *ip, + const struct timespec64 tv) +{ + struct xfs_legacy_timestamp *lts; + xfs_timestamp_t ts; + + if (xfs_inode_has_bigtime(ip)) + return cpu_to_be64(xfs_inode_encode_bigtime(tv)); + + lts = (struct xfs_legacy_timestamp *)&ts; + lts->t_sec = cpu_to_be32(tv.tv_sec); + lts->t_nsec = cpu_to_be32(tv.tv_nsec); + + return ts; +} + +static inline void +xfs_inode_to_disk_iext_counters( + struct xfs_inode *ip, + struct xfs_dinode *to) +{ + if (xfs_inode_has_large_extent_counts(ip)) { + to->di_big_nextents = cpu_to_be64(xfs_ifork_nextents(&ip->i_df)); + to->di_big_anextents = cpu_to_be32(xfs_ifork_nextents(&ip->i_af)); + /* + * We might be upgrading the inode to use larger extent counters + * than was previously used. Hence zero the unused field. + */ + to->di_nrext64_pad = cpu_to_be16(0); + } else { + to->di_nextents = cpu_to_be32(xfs_ifork_nextents(&ip->i_df)); + to->di_anextents = cpu_to_be16(xfs_ifork_nextents(&ip->i_af)); + } +} + +void +xfs_inode_to_disk( + struct xfs_inode *ip, + struct xfs_dinode *to, + xfs_lsn_t lsn) +{ + struct inode *inode = VFS_I(ip); + + to->di_magic = cpu_to_be16(XFS_DINODE_MAGIC); + to->di_onlink = 0; + + to->di_format = xfs_ifork_format(&ip->i_df); + to->di_uid = cpu_to_be32(i_uid_read(inode)); + to->di_gid = cpu_to_be32(i_gid_read(inode)); + to->di_projid_lo = cpu_to_be16(ip->i_projid & 0xffff); + to->di_projid_hi = cpu_to_be16(ip->i_projid >> 16); + + to->di_atime = xfs_inode_to_disk_ts(ip, inode->i_atime); + to->di_mtime = xfs_inode_to_disk_ts(ip, inode->i_mtime); + to->di_ctime = xfs_inode_to_disk_ts(ip, inode->i_ctime); + to->di_nlink = cpu_to_be32(inode->i_nlink); + to->di_gen = cpu_to_be32(inode->i_generation); + to->di_mode = cpu_to_be16(inode->i_mode); + + to->di_size = cpu_to_be64(ip->i_disk_size); + to->di_nblocks = cpu_to_be64(ip->i_nblocks); + to->di_extsize = cpu_to_be32(ip->i_extsize); + to->di_forkoff = ip->i_forkoff; + to->di_aformat = xfs_ifork_format(&ip->i_af); + to->di_flags = cpu_to_be16(ip->i_diflags); + + if (xfs_has_v3inodes(ip->i_mount)) { + to->di_version = 3; + to->di_changecount = cpu_to_be64(inode_peek_iversion(inode)); + to->di_crtime = xfs_inode_to_disk_ts(ip, ip->i_crtime); + to->di_flags2 = cpu_to_be64(ip->i_diflags2); + to->di_cowextsize = cpu_to_be32(ip->i_cowextsize); + to->di_ino = cpu_to_be64(ip->i_ino); + to->di_lsn = cpu_to_be64(lsn); + memset(to->di_pad2, 0, sizeof(to->di_pad2)); + uuid_copy(&to->di_uuid, &ip->i_mount->m_sb.sb_meta_uuid); + to->di_v3_pad = 0; + } else { + to->di_version = 2; + to->di_flushiter = cpu_to_be16(ip->i_flushiter); + memset(to->di_v2_pad, 0, sizeof(to->di_v2_pad)); + } + + xfs_inode_to_disk_iext_counters(ip, to); +} + +static xfs_failaddr_t +xfs_dinode_verify_fork( + struct xfs_dinode *dip, + struct xfs_mount *mp, + int whichfork) +{ + xfs_extnum_t di_nextents; + xfs_extnum_t max_extents; + mode_t mode = be16_to_cpu(dip->di_mode); + uint32_t fork_size = XFS_DFORK_SIZE(dip, mp, whichfork); + uint32_t fork_format = XFS_DFORK_FORMAT(dip, whichfork); + + di_nextents = xfs_dfork_nextents(dip, whichfork); + + /* + * For fork types that can contain local data, check that the fork + * format matches the size of local data contained within the fork. + * + * For all types, check that when the size says the should be in extent + * or btree format, the inode isn't claiming it is in local format. + */ + if (whichfork == XFS_DATA_FORK) { + if (S_ISDIR(mode) || S_ISLNK(mode)) { + if (be64_to_cpu(dip->di_size) <= fork_size && + fork_format != XFS_DINODE_FMT_LOCAL) + return __this_address; + } + + if (be64_to_cpu(dip->di_size) > fork_size && + fork_format == XFS_DINODE_FMT_LOCAL) + return __this_address; + } + + switch (fork_format) { + case XFS_DINODE_FMT_LOCAL: + /* + * No local regular files yet. + */ + if (S_ISREG(mode) && whichfork == XFS_DATA_FORK) + return __this_address; + if (di_nextents) + return __this_address; + break; + case XFS_DINODE_FMT_EXTENTS: + if (di_nextents > XFS_DFORK_MAXEXT(dip, mp, whichfork)) + return __this_address; + break; + case XFS_DINODE_FMT_BTREE: + max_extents = xfs_iext_max_nextents( + xfs_dinode_has_large_extent_counts(dip), + whichfork); + if (di_nextents > max_extents) + return __this_address; + break; + default: + return __this_address; + } + return NULL; +} + +static xfs_failaddr_t +xfs_dinode_verify_forkoff( + struct xfs_dinode *dip, + struct xfs_mount *mp) +{ + if (!dip->di_forkoff) + return NULL; + + switch (dip->di_format) { + case XFS_DINODE_FMT_DEV: + if (dip->di_forkoff != (roundup(sizeof(xfs_dev_t), 8) >> 3)) + return __this_address; + break; + case XFS_DINODE_FMT_LOCAL: /* fall through ... */ + case XFS_DINODE_FMT_EXTENTS: /* fall through ... */ + case XFS_DINODE_FMT_BTREE: + if (dip->di_forkoff >= (XFS_LITINO(mp) >> 3)) + return __this_address; + break; + default: + return __this_address; + } + return NULL; +} + +static xfs_failaddr_t +xfs_dinode_verify_nrext64( + struct xfs_mount *mp, + struct xfs_dinode *dip) +{ + if (xfs_dinode_has_large_extent_counts(dip)) { + if (!xfs_has_large_extent_counts(mp)) + return __this_address; + if (dip->di_nrext64_pad != 0) + return __this_address; + } else if (dip->di_version >= 3) { + if (dip->di_v3_pad != 0) + return __this_address; + } + + return NULL; +} + +xfs_failaddr_t +xfs_dinode_verify( + struct xfs_mount *mp, + xfs_ino_t ino, + struct xfs_dinode *dip) +{ + xfs_failaddr_t fa; + uint16_t mode; + uint16_t flags; + uint64_t flags2; + uint64_t di_size; + xfs_extnum_t nextents; + xfs_extnum_t naextents; + xfs_filblks_t nblocks; + + if (dip->di_magic != cpu_to_be16(XFS_DINODE_MAGIC)) + return __this_address; + + /* Verify v3 integrity information first */ + if (dip->di_version >= 3) { + if (!xfs_has_v3inodes(mp)) + return __this_address; + if (!xfs_verify_cksum((char *)dip, mp->m_sb.sb_inodesize, + XFS_DINODE_CRC_OFF)) + return __this_address; + if (be64_to_cpu(dip->di_ino) != ino) + return __this_address; + if (!uuid_equal(&dip->di_uuid, &mp->m_sb.sb_meta_uuid)) + return __this_address; + } + + /* don't allow invalid i_size */ + di_size = be64_to_cpu(dip->di_size); + if (di_size & (1ULL << 63)) + return __this_address; + + mode = be16_to_cpu(dip->di_mode); + if (mode && xfs_mode_to_ftype(mode) == XFS_DIR3_FT_UNKNOWN) + return __this_address; + + /* No zero-length symlinks/dirs. */ + if ((S_ISLNK(mode) || S_ISDIR(mode)) && di_size == 0) + return __this_address; + + fa = xfs_dinode_verify_nrext64(mp, dip); + if (fa) + return fa; + + nextents = xfs_dfork_data_extents(dip); + naextents = xfs_dfork_attr_extents(dip); + nblocks = be64_to_cpu(dip->di_nblocks); + + /* Fork checks carried over from xfs_iformat_fork */ + if (mode && nextents + naextents > nblocks) + return __this_address; + + if (S_ISDIR(mode) && nextents > mp->m_dir_geo->max_extents) + return __this_address; + + if (mode && XFS_DFORK_BOFF(dip) > mp->m_sb.sb_inodesize) + return __this_address; + + flags = be16_to_cpu(dip->di_flags); + + if (mode && (flags & XFS_DIFLAG_REALTIME) && !mp->m_rtdev_targp) + return __this_address; + + /* check for illegal values of forkoff */ + fa = xfs_dinode_verify_forkoff(dip, mp); + if (fa) + return fa; + + /* Do we have appropriate data fork formats for the mode? */ + switch (mode & S_IFMT) { + case S_IFIFO: + case S_IFCHR: + case S_IFBLK: + case S_IFSOCK: + if (dip->di_format != XFS_DINODE_FMT_DEV) + return __this_address; + break; + case S_IFREG: + case S_IFLNK: + case S_IFDIR: + fa = xfs_dinode_verify_fork(dip, mp, XFS_DATA_FORK); + if (fa) + return fa; + break; + case 0: + /* Uninitialized inode ok. */ + break; + default: + return __this_address; + } + + if (dip->di_forkoff) { + fa = xfs_dinode_verify_fork(dip, mp, XFS_ATTR_FORK); + if (fa) + return fa; + } else { + /* + * If there is no fork offset, this may be a freshly-made inode + * in a new disk cluster, in which case di_aformat is zeroed. + * Otherwise, such an inode must be in EXTENTS format; this goes + * for freed inodes as well. + */ + switch (dip->di_aformat) { + case 0: + case XFS_DINODE_FMT_EXTENTS: + break; + default: + return __this_address; + } + if (naextents) + return __this_address; + } + + /* extent size hint validation */ + fa = xfs_inode_validate_extsize(mp, be32_to_cpu(dip->di_extsize), + mode, flags); + if (fa) + return fa; + + /* only version 3 or greater inodes are extensively verified here */ + if (dip->di_version < 3) + return NULL; + + flags2 = be64_to_cpu(dip->di_flags2); + + /* don't allow reflink/cowextsize if we don't have reflink */ + if ((flags2 & (XFS_DIFLAG2_REFLINK | XFS_DIFLAG2_COWEXTSIZE)) && + !xfs_has_reflink(mp)) + return __this_address; + + /* only regular files get reflink */ + if ((flags2 & XFS_DIFLAG2_REFLINK) && (mode & S_IFMT) != S_IFREG) + return __this_address; + + /* don't let reflink and realtime mix */ + if ((flags2 & XFS_DIFLAG2_REFLINK) && (flags & XFS_DIFLAG_REALTIME)) + return __this_address; + + /* COW extent size hint validation */ + fa = xfs_inode_validate_cowextsize(mp, be32_to_cpu(dip->di_cowextsize), + mode, flags, flags2); + if (fa) + return fa; + + /* bigtime iflag can only happen on bigtime filesystems */ + if (xfs_dinode_has_bigtime(dip) && + !xfs_has_bigtime(mp)) + return __this_address; + + return NULL; +} + +void +xfs_dinode_calc_crc( + struct xfs_mount *mp, + struct xfs_dinode *dip) +{ + uint32_t crc; + + if (dip->di_version < 3) + return; + + ASSERT(xfs_has_crc(mp)); + crc = xfs_start_cksum_update((char *)dip, mp->m_sb.sb_inodesize, + XFS_DINODE_CRC_OFF); + dip->di_crc = xfs_end_cksum(crc); +} + +/* + * Validate di_extsize hint. + * + * 1. Extent size hint is only valid for directories and regular files. + * 2. FS_XFLAG_EXTSIZE is only valid for regular files. + * 3. FS_XFLAG_EXTSZINHERIT is only valid for directories. + * 4. Hint cannot be larger than MAXTEXTLEN. + * 5. Can be changed on directories at any time. + * 6. Hint value of 0 turns off hints, clears inode flags. + * 7. Extent size must be a multiple of the appropriate block size. + * For realtime files, this is the rt extent size. + * 8. For non-realtime files, the extent size hint must be limited + * to half the AG size to avoid alignment extending the extent beyond the + * limits of the AG. + */ +xfs_failaddr_t +xfs_inode_validate_extsize( + struct xfs_mount *mp, + uint32_t extsize, + uint16_t mode, + uint16_t flags) +{ + bool rt_flag; + bool hint_flag; + bool inherit_flag; + uint32_t extsize_bytes; + uint32_t blocksize_bytes; + + rt_flag = (flags & XFS_DIFLAG_REALTIME); + hint_flag = (flags & XFS_DIFLAG_EXTSIZE); + inherit_flag = (flags & XFS_DIFLAG_EXTSZINHERIT); + extsize_bytes = XFS_FSB_TO_B(mp, extsize); + + /* + * This comment describes a historic gap in this verifier function. + * + * For a directory with both RTINHERIT and EXTSZINHERIT flags set, this + * function has never checked that the extent size hint is an integer + * multiple of the realtime extent size. Since we allow users to set + * this combination on non-rt filesystems /and/ to change the rt + * extent size when adding a rt device to a filesystem, the net effect + * is that users can configure a filesystem anticipating one rt + * geometry and change their minds later. Directories do not use the + * extent size hint, so this is harmless for them. + * + * If a directory with a misaligned extent size hint is allowed to + * propagate that hint into a new regular realtime file, the result + * is that the inode cluster buffer verifier will trigger a corruption + * shutdown the next time it is run, because the verifier has always + * enforced the alignment rule for regular files. + * + * Because we allow administrators to set a new rt extent size when + * adding a rt section, we cannot add a check to this verifier because + * that will result a new source of directory corruption errors when + * reading an existing filesystem. Instead, we rely on callers to + * decide when alignment checks are appropriate, and fix things up as + * needed. + */ + + if (rt_flag) + blocksize_bytes = XFS_FSB_TO_B(mp, mp->m_sb.sb_rextsize); + else + blocksize_bytes = mp->m_sb.sb_blocksize; + + if ((hint_flag || inherit_flag) && !(S_ISDIR(mode) || S_ISREG(mode))) + return __this_address; + + if (hint_flag && !S_ISREG(mode)) + return __this_address; + + if (inherit_flag && !S_ISDIR(mode)) + return __this_address; + + if ((hint_flag || inherit_flag) && extsize == 0) + return __this_address; + + /* free inodes get flags set to zero but extsize remains */ + if (mode && !(hint_flag || inherit_flag) && extsize != 0) + return __this_address; + + if (extsize_bytes % blocksize_bytes) + return __this_address; + + if (extsize > XFS_MAX_BMBT_EXTLEN) + return __this_address; + + if (!rt_flag && extsize > mp->m_sb.sb_agblocks / 2) + return __this_address; + + return NULL; +} + +/* + * Validate di_cowextsize hint. + * + * 1. CoW extent size hint can only be set if reflink is enabled on the fs. + * The inode does not have to have any shared blocks, but it must be a v3. + * 2. FS_XFLAG_COWEXTSIZE is only valid for directories and regular files; + * for a directory, the hint is propagated to new files. + * 3. Can be changed on files & directories at any time. + * 4. Hint value of 0 turns off hints, clears inode flags. + * 5. Extent size must be a multiple of the appropriate block size. + * 6. The extent size hint must be limited to half the AG size to avoid + * alignment extending the extent beyond the limits of the AG. + */ +xfs_failaddr_t +xfs_inode_validate_cowextsize( + struct xfs_mount *mp, + uint32_t cowextsize, + uint16_t mode, + uint16_t flags, + uint64_t flags2) +{ + bool rt_flag; + bool hint_flag; + uint32_t cowextsize_bytes; + + rt_flag = (flags & XFS_DIFLAG_REALTIME); + hint_flag = (flags2 & XFS_DIFLAG2_COWEXTSIZE); + cowextsize_bytes = XFS_FSB_TO_B(mp, cowextsize); + + if (hint_flag && !xfs_has_reflink(mp)) + return __this_address; + + if (hint_flag && !(S_ISDIR(mode) || S_ISREG(mode))) + return __this_address; + + if (hint_flag && cowextsize == 0) + return __this_address; + + /* free inodes get flags set to zero but cowextsize remains */ + if (mode && !hint_flag && cowextsize != 0) + return __this_address; + + if (hint_flag && rt_flag) + return __this_address; + + if (cowextsize_bytes % mp->m_sb.sb_blocksize) + return __this_address; + + if (cowextsize > XFS_MAX_BMBT_EXTLEN) + return __this_address; + + if (cowextsize > mp->m_sb.sb_agblocks / 2) + return __this_address; + + return NULL; +} |