diff options
Diffstat (limited to 'fs/xfs/libxfs/xfs_inode_fork.c')
-rw-r--r-- | fs/xfs/libxfs/xfs_inode_fork.c | 794 |
1 files changed, 794 insertions, 0 deletions
diff --git a/fs/xfs/libxfs/xfs_inode_fork.c b/fs/xfs/libxfs/xfs_inode_fork.c new file mode 100644 index 0000000000..5a2e7ddfa7 --- /dev/null +++ b/fs/xfs/libxfs/xfs_inode_fork.c @@ -0,0 +1,794 @@ +// 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_inode.h" +#include "xfs_trans.h" +#include "xfs_inode_item.h" +#include "xfs_btree.h" +#include "xfs_bmap_btree.h" +#include "xfs_bmap.h" +#include "xfs_error.h" +#include "xfs_trace.h" +#include "xfs_da_format.h" +#include "xfs_da_btree.h" +#include "xfs_dir2_priv.h" +#include "xfs_attr_leaf.h" +#include "xfs_types.h" +#include "xfs_errortag.h" + +struct kmem_cache *xfs_ifork_cache; + +void +xfs_init_local_fork( + struct xfs_inode *ip, + int whichfork, + const void *data, + int64_t size) +{ + struct xfs_ifork *ifp = xfs_ifork_ptr(ip, whichfork); + int mem_size = size; + bool zero_terminate; + + /* + * If we are using the local fork to store a symlink body we need to + * zero-terminate it so that we can pass it back to the VFS directly. + * Overallocate the in-memory fork by one for that and add a zero + * to terminate it below. + */ + zero_terminate = S_ISLNK(VFS_I(ip)->i_mode); + if (zero_terminate) + mem_size++; + + if (size) { + ifp->if_u1.if_data = kmem_alloc(mem_size, KM_NOFS); + memcpy(ifp->if_u1.if_data, data, size); + if (zero_terminate) + ifp->if_u1.if_data[size] = '\0'; + } else { + ifp->if_u1.if_data = NULL; + } + + ifp->if_bytes = size; +} + +/* + * The file is in-lined in the on-disk inode. + */ +STATIC int +xfs_iformat_local( + struct xfs_inode *ip, + struct xfs_dinode *dip, + int whichfork, + int size) +{ + /* + * If the size is unreasonable, then something + * is wrong and we just bail out rather than crash in + * kmem_alloc() or memcpy() below. + */ + if (unlikely(size > XFS_DFORK_SIZE(dip, ip->i_mount, whichfork))) { + xfs_warn(ip->i_mount, + "corrupt inode %llu (bad size %d for local fork, size = %zd).", + (unsigned long long) ip->i_ino, size, + XFS_DFORK_SIZE(dip, ip->i_mount, whichfork)); + xfs_inode_verifier_error(ip, -EFSCORRUPTED, + "xfs_iformat_local", dip, sizeof(*dip), + __this_address); + return -EFSCORRUPTED; + } + + xfs_init_local_fork(ip, whichfork, XFS_DFORK_PTR(dip, whichfork), size); + return 0; +} + +/* + * The file consists of a set of extents all of which fit into the on-disk + * inode. + */ +STATIC int +xfs_iformat_extents( + struct xfs_inode *ip, + struct xfs_dinode *dip, + int whichfork) +{ + struct xfs_mount *mp = ip->i_mount; + struct xfs_ifork *ifp = xfs_ifork_ptr(ip, whichfork); + int state = xfs_bmap_fork_to_state(whichfork); + xfs_extnum_t nex = xfs_dfork_nextents(dip, whichfork); + int size = nex * sizeof(xfs_bmbt_rec_t); + struct xfs_iext_cursor icur; + struct xfs_bmbt_rec *dp; + struct xfs_bmbt_irec new; + int i; + + /* + * If the number of extents is unreasonable, then something is wrong and + * we just bail out rather than crash in kmem_alloc() or memcpy() below. + */ + if (unlikely(size < 0 || size > XFS_DFORK_SIZE(dip, mp, whichfork))) { + xfs_warn(ip->i_mount, "corrupt inode %llu ((a)extents = %llu).", + ip->i_ino, nex); + xfs_inode_verifier_error(ip, -EFSCORRUPTED, + "xfs_iformat_extents(1)", dip, sizeof(*dip), + __this_address); + return -EFSCORRUPTED; + } + + ifp->if_bytes = 0; + ifp->if_u1.if_root = NULL; + ifp->if_height = 0; + if (size) { + dp = (xfs_bmbt_rec_t *) XFS_DFORK_PTR(dip, whichfork); + + xfs_iext_first(ifp, &icur); + for (i = 0; i < nex; i++, dp++) { + xfs_failaddr_t fa; + + xfs_bmbt_disk_get_all(dp, &new); + fa = xfs_bmap_validate_extent(ip, whichfork, &new); + if (fa) { + xfs_inode_verifier_error(ip, -EFSCORRUPTED, + "xfs_iformat_extents(2)", + dp, sizeof(*dp), fa); + return xfs_bmap_complain_bad_rec(ip, whichfork, + fa, &new); + } + + xfs_iext_insert(ip, &icur, &new, state); + trace_xfs_read_extent(ip, &icur, state, _THIS_IP_); + xfs_iext_next(ifp, &icur); + } + } + return 0; +} + +/* + * The file has too many extents to fit into + * the inode, so they are in B-tree format. + * Allocate a buffer for the root of the B-tree + * and copy the root into it. The i_extents + * field will remain NULL until all of the + * extents are read in (when they are needed). + */ +STATIC int +xfs_iformat_btree( + struct xfs_inode *ip, + struct xfs_dinode *dip, + int whichfork) +{ + struct xfs_mount *mp = ip->i_mount; + xfs_bmdr_block_t *dfp; + struct xfs_ifork *ifp; + /* REFERENCED */ + int nrecs; + int size; + int level; + + ifp = xfs_ifork_ptr(ip, whichfork); + dfp = (xfs_bmdr_block_t *)XFS_DFORK_PTR(dip, whichfork); + size = XFS_BMAP_BROOT_SPACE(mp, dfp); + nrecs = be16_to_cpu(dfp->bb_numrecs); + level = be16_to_cpu(dfp->bb_level); + + /* + * blow out if -- fork has less extents than can fit in + * fork (fork shouldn't be a btree format), root btree + * block has more records than can fit into the fork, + * or the number of extents is greater than the number of + * blocks. + */ + if (unlikely(ifp->if_nextents <= XFS_IFORK_MAXEXT(ip, whichfork) || + nrecs == 0 || + XFS_BMDR_SPACE_CALC(nrecs) > + XFS_DFORK_SIZE(dip, mp, whichfork) || + ifp->if_nextents > ip->i_nblocks) || + level == 0 || level > XFS_BM_MAXLEVELS(mp, whichfork)) { + xfs_warn(mp, "corrupt inode %llu (btree).", + (unsigned long long) ip->i_ino); + xfs_inode_verifier_error(ip, -EFSCORRUPTED, + "xfs_iformat_btree", dfp, size, + __this_address); + return -EFSCORRUPTED; + } + + ifp->if_broot_bytes = size; + ifp->if_broot = kmem_alloc(size, KM_NOFS); + ASSERT(ifp->if_broot != NULL); + /* + * Copy and convert from the on-disk structure + * to the in-memory structure. + */ + xfs_bmdr_to_bmbt(ip, dfp, XFS_DFORK_SIZE(dip, ip->i_mount, whichfork), + ifp->if_broot, size); + + ifp->if_bytes = 0; + ifp->if_u1.if_root = NULL; + ifp->if_height = 0; + return 0; +} + +int +xfs_iformat_data_fork( + struct xfs_inode *ip, + struct xfs_dinode *dip) +{ + struct inode *inode = VFS_I(ip); + int error; + + /* + * Initialize the extent count early, as the per-format routines may + * depend on it. Use release semantics to set needextents /after/ we + * set the format. This ensures that we can use acquire semantics on + * needextents in xfs_need_iread_extents() and be guaranteed to see a + * valid format value after that load. + */ + ip->i_df.if_format = dip->di_format; + ip->i_df.if_nextents = xfs_dfork_data_extents(dip); + smp_store_release(&ip->i_df.if_needextents, + ip->i_df.if_format == XFS_DINODE_FMT_BTREE ? 1 : 0); + + switch (inode->i_mode & S_IFMT) { + case S_IFIFO: + case S_IFCHR: + case S_IFBLK: + case S_IFSOCK: + ip->i_disk_size = 0; + inode->i_rdev = xfs_to_linux_dev_t(xfs_dinode_get_rdev(dip)); + return 0; + case S_IFREG: + case S_IFLNK: + case S_IFDIR: + switch (ip->i_df.if_format) { + case XFS_DINODE_FMT_LOCAL: + error = xfs_iformat_local(ip, dip, XFS_DATA_FORK, + be64_to_cpu(dip->di_size)); + if (!error) + error = xfs_ifork_verify_local_data(ip); + return error; + case XFS_DINODE_FMT_EXTENTS: + return xfs_iformat_extents(ip, dip, XFS_DATA_FORK); + case XFS_DINODE_FMT_BTREE: + return xfs_iformat_btree(ip, dip, XFS_DATA_FORK); + default: + xfs_inode_verifier_error(ip, -EFSCORRUPTED, __func__, + dip, sizeof(*dip), __this_address); + return -EFSCORRUPTED; + } + break; + default: + xfs_inode_verifier_error(ip, -EFSCORRUPTED, __func__, dip, + sizeof(*dip), __this_address); + return -EFSCORRUPTED; + } +} + +static uint16_t +xfs_dfork_attr_shortform_size( + struct xfs_dinode *dip) +{ + struct xfs_attr_shortform *atp = + (struct xfs_attr_shortform *)XFS_DFORK_APTR(dip); + + return be16_to_cpu(atp->hdr.totsize); +} + +void +xfs_ifork_init_attr( + struct xfs_inode *ip, + enum xfs_dinode_fmt format, + xfs_extnum_t nextents) +{ + /* + * Initialize the extent count early, as the per-format routines may + * depend on it. Use release semantics to set needextents /after/ we + * set the format. This ensures that we can use acquire semantics on + * needextents in xfs_need_iread_extents() and be guaranteed to see a + * valid format value after that load. + */ + ip->i_af.if_format = format; + ip->i_af.if_nextents = nextents; + smp_store_release(&ip->i_af.if_needextents, + ip->i_af.if_format == XFS_DINODE_FMT_BTREE ? 1 : 0); +} + +void +xfs_ifork_zap_attr( + struct xfs_inode *ip) +{ + xfs_idestroy_fork(&ip->i_af); + memset(&ip->i_af, 0, sizeof(struct xfs_ifork)); + ip->i_af.if_format = XFS_DINODE_FMT_EXTENTS; +} + +int +xfs_iformat_attr_fork( + struct xfs_inode *ip, + struct xfs_dinode *dip) +{ + xfs_extnum_t naextents = xfs_dfork_attr_extents(dip); + int error = 0; + + /* + * Initialize the extent count early, as the per-format routines may + * depend on it. + */ + xfs_ifork_init_attr(ip, dip->di_aformat, naextents); + + switch (ip->i_af.if_format) { + case XFS_DINODE_FMT_LOCAL: + error = xfs_iformat_local(ip, dip, XFS_ATTR_FORK, + xfs_dfork_attr_shortform_size(dip)); + if (!error) + error = xfs_ifork_verify_local_attr(ip); + break; + case XFS_DINODE_FMT_EXTENTS: + error = xfs_iformat_extents(ip, dip, XFS_ATTR_FORK); + break; + case XFS_DINODE_FMT_BTREE: + error = xfs_iformat_btree(ip, dip, XFS_ATTR_FORK); + break; + default: + xfs_inode_verifier_error(ip, error, __func__, dip, + sizeof(*dip), __this_address); + error = -EFSCORRUPTED; + break; + } + + if (error) + xfs_ifork_zap_attr(ip); + return error; +} + +/* + * Reallocate the space for if_broot based on the number of records + * being added or deleted as indicated in rec_diff. Move the records + * and pointers in if_broot to fit the new size. When shrinking this + * will eliminate holes between the records and pointers created by + * the caller. When growing this will create holes to be filled in + * by the caller. + * + * The caller must not request to add more records than would fit in + * the on-disk inode root. If the if_broot is currently NULL, then + * if we are adding records, one will be allocated. The caller must also + * not request that the number of records go below zero, although + * it can go to zero. + * + * ip -- the inode whose if_broot area is changing + * ext_diff -- the change in the number of records, positive or negative, + * requested for the if_broot array. + */ +void +xfs_iroot_realloc( + xfs_inode_t *ip, + int rec_diff, + int whichfork) +{ + struct xfs_mount *mp = ip->i_mount; + int cur_max; + struct xfs_ifork *ifp; + struct xfs_btree_block *new_broot; + int new_max; + size_t new_size; + char *np; + char *op; + + /* + * Handle the degenerate case quietly. + */ + if (rec_diff == 0) { + return; + } + + ifp = xfs_ifork_ptr(ip, whichfork); + if (rec_diff > 0) { + /* + * If there wasn't any memory allocated before, just + * allocate it now and get out. + */ + if (ifp->if_broot_bytes == 0) { + new_size = XFS_BMAP_BROOT_SPACE_CALC(mp, rec_diff); + ifp->if_broot = kmem_alloc(new_size, KM_NOFS); + ifp->if_broot_bytes = (int)new_size; + return; + } + + /* + * If there is already an existing if_broot, then we need + * to realloc() it and shift the pointers to their new + * location. The records don't change location because + * they are kept butted up against the btree block header. + */ + cur_max = xfs_bmbt_maxrecs(mp, ifp->if_broot_bytes, 0); + new_max = cur_max + rec_diff; + new_size = XFS_BMAP_BROOT_SPACE_CALC(mp, new_max); + ifp->if_broot = krealloc(ifp->if_broot, new_size, + GFP_NOFS | __GFP_NOFAIL); + op = (char *)XFS_BMAP_BROOT_PTR_ADDR(mp, ifp->if_broot, 1, + ifp->if_broot_bytes); + np = (char *)XFS_BMAP_BROOT_PTR_ADDR(mp, ifp->if_broot, 1, + (int)new_size); + ifp->if_broot_bytes = (int)new_size; + ASSERT(XFS_BMAP_BMDR_SPACE(ifp->if_broot) <= + xfs_inode_fork_size(ip, whichfork)); + memmove(np, op, cur_max * (uint)sizeof(xfs_fsblock_t)); + return; + } + + /* + * rec_diff is less than 0. In this case, we are shrinking the + * if_broot buffer. It must already exist. If we go to zero + * records, just get rid of the root and clear the status bit. + */ + ASSERT((ifp->if_broot != NULL) && (ifp->if_broot_bytes > 0)); + cur_max = xfs_bmbt_maxrecs(mp, ifp->if_broot_bytes, 0); + new_max = cur_max + rec_diff; + ASSERT(new_max >= 0); + if (new_max > 0) + new_size = XFS_BMAP_BROOT_SPACE_CALC(mp, new_max); + else + new_size = 0; + if (new_size > 0) { + new_broot = kmem_alloc(new_size, KM_NOFS); + /* + * First copy over the btree block header. + */ + memcpy(new_broot, ifp->if_broot, + XFS_BMBT_BLOCK_LEN(ip->i_mount)); + } else { + new_broot = NULL; + } + + /* + * Only copy the records and pointers if there are any. + */ + if (new_max > 0) { + /* + * First copy the records. + */ + op = (char *)XFS_BMBT_REC_ADDR(mp, ifp->if_broot, 1); + np = (char *)XFS_BMBT_REC_ADDR(mp, new_broot, 1); + memcpy(np, op, new_max * (uint)sizeof(xfs_bmbt_rec_t)); + + /* + * Then copy the pointers. + */ + op = (char *)XFS_BMAP_BROOT_PTR_ADDR(mp, ifp->if_broot, 1, + ifp->if_broot_bytes); + np = (char *)XFS_BMAP_BROOT_PTR_ADDR(mp, new_broot, 1, + (int)new_size); + memcpy(np, op, new_max * (uint)sizeof(xfs_fsblock_t)); + } + kmem_free(ifp->if_broot); + ifp->if_broot = new_broot; + ifp->if_broot_bytes = (int)new_size; + if (ifp->if_broot) + ASSERT(XFS_BMAP_BMDR_SPACE(ifp->if_broot) <= + xfs_inode_fork_size(ip, whichfork)); + return; +} + + +/* + * This is called when the amount of space needed for if_data + * is increased or decreased. The change in size is indicated by + * the number of bytes that need to be added or deleted in the + * byte_diff parameter. + * + * If the amount of space needed has decreased below the size of the + * inline buffer, then switch to using the inline buffer. Otherwise, + * use kmem_realloc() or kmem_alloc() to adjust the size of the buffer + * to what is needed. + * + * ip -- the inode whose if_data area is changing + * byte_diff -- the change in the number of bytes, positive or negative, + * requested for the if_data array. + */ +void +xfs_idata_realloc( + struct xfs_inode *ip, + int64_t byte_diff, + int whichfork) +{ + struct xfs_ifork *ifp = xfs_ifork_ptr(ip, whichfork); + int64_t new_size = ifp->if_bytes + byte_diff; + + ASSERT(new_size >= 0); + ASSERT(new_size <= xfs_inode_fork_size(ip, whichfork)); + + if (byte_diff == 0) + return; + + if (new_size == 0) { + kmem_free(ifp->if_u1.if_data); + ifp->if_u1.if_data = NULL; + ifp->if_bytes = 0; + return; + } + + ifp->if_u1.if_data = krealloc(ifp->if_u1.if_data, new_size, + GFP_NOFS | __GFP_NOFAIL); + ifp->if_bytes = new_size; +} + +void +xfs_idestroy_fork( + struct xfs_ifork *ifp) +{ + if (ifp->if_broot != NULL) { + kmem_free(ifp->if_broot); + ifp->if_broot = NULL; + } + + switch (ifp->if_format) { + case XFS_DINODE_FMT_LOCAL: + kmem_free(ifp->if_u1.if_data); + ifp->if_u1.if_data = NULL; + break; + case XFS_DINODE_FMT_EXTENTS: + case XFS_DINODE_FMT_BTREE: + if (ifp->if_height) + xfs_iext_destroy(ifp); + break; + } +} + +/* + * Convert in-core extents to on-disk form + * + * In the case of the data fork, the in-core and on-disk fork sizes can be + * different due to delayed allocation extents. We only copy on-disk extents + * here, so callers must always use the physical fork size to determine the + * size of the buffer passed to this routine. We will return the size actually + * used. + */ +int +xfs_iextents_copy( + struct xfs_inode *ip, + struct xfs_bmbt_rec *dp, + int whichfork) +{ + int state = xfs_bmap_fork_to_state(whichfork); + struct xfs_ifork *ifp = xfs_ifork_ptr(ip, whichfork); + struct xfs_iext_cursor icur; + struct xfs_bmbt_irec rec; + int64_t copied = 0; + + ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL | XFS_ILOCK_SHARED)); + ASSERT(ifp->if_bytes > 0); + + for_each_xfs_iext(ifp, &icur, &rec) { + if (isnullstartblock(rec.br_startblock)) + continue; + ASSERT(xfs_bmap_validate_extent(ip, whichfork, &rec) == NULL); + xfs_bmbt_disk_set_all(dp, &rec); + trace_xfs_write_extent(ip, &icur, state, _RET_IP_); + copied += sizeof(struct xfs_bmbt_rec); + dp++; + } + + ASSERT(copied > 0); + ASSERT(copied <= ifp->if_bytes); + return copied; +} + +/* + * Each of the following cases stores data into the same region + * of the on-disk inode, so only one of them can be valid at + * any given time. While it is possible to have conflicting formats + * and log flags, e.g. having XFS_ILOG_?DATA set when the fork is + * in EXTENTS format, this can only happen when the fork has + * changed formats after being modified but before being flushed. + * In these cases, the format always takes precedence, because the + * format indicates the current state of the fork. + */ +void +xfs_iflush_fork( + struct xfs_inode *ip, + struct xfs_dinode *dip, + struct xfs_inode_log_item *iip, + int whichfork) +{ + char *cp; + struct xfs_ifork *ifp; + xfs_mount_t *mp; + static const short brootflag[2] = + { XFS_ILOG_DBROOT, XFS_ILOG_ABROOT }; + static const short dataflag[2] = + { XFS_ILOG_DDATA, XFS_ILOG_ADATA }; + static const short extflag[2] = + { XFS_ILOG_DEXT, XFS_ILOG_AEXT }; + + if (!iip) + return; + ifp = xfs_ifork_ptr(ip, whichfork); + /* + * This can happen if we gave up in iformat in an error path, + * for the attribute fork. + */ + if (!ifp) { + ASSERT(whichfork == XFS_ATTR_FORK); + return; + } + cp = XFS_DFORK_PTR(dip, whichfork); + mp = ip->i_mount; + switch (ifp->if_format) { + case XFS_DINODE_FMT_LOCAL: + if ((iip->ili_fields & dataflag[whichfork]) && + (ifp->if_bytes > 0)) { + ASSERT(ifp->if_u1.if_data != NULL); + ASSERT(ifp->if_bytes <= xfs_inode_fork_size(ip, whichfork)); + memcpy(cp, ifp->if_u1.if_data, ifp->if_bytes); + } + break; + + case XFS_DINODE_FMT_EXTENTS: + if ((iip->ili_fields & extflag[whichfork]) && + (ifp->if_bytes > 0)) { + ASSERT(ifp->if_nextents > 0); + (void)xfs_iextents_copy(ip, (xfs_bmbt_rec_t *)cp, + whichfork); + } + break; + + case XFS_DINODE_FMT_BTREE: + if ((iip->ili_fields & brootflag[whichfork]) && + (ifp->if_broot_bytes > 0)) { + ASSERT(ifp->if_broot != NULL); + ASSERT(XFS_BMAP_BMDR_SPACE(ifp->if_broot) <= + xfs_inode_fork_size(ip, whichfork)); + xfs_bmbt_to_bmdr(mp, ifp->if_broot, ifp->if_broot_bytes, + (xfs_bmdr_block_t *)cp, + XFS_DFORK_SIZE(dip, mp, whichfork)); + } + break; + + case XFS_DINODE_FMT_DEV: + if (iip->ili_fields & XFS_ILOG_DEV) { + ASSERT(whichfork == XFS_DATA_FORK); + xfs_dinode_put_rdev(dip, + linux_to_xfs_dev_t(VFS_I(ip)->i_rdev)); + } + break; + + default: + ASSERT(0); + break; + } +} + +/* Convert bmap state flags to an inode fork. */ +struct xfs_ifork * +xfs_iext_state_to_fork( + struct xfs_inode *ip, + int state) +{ + if (state & BMAP_COWFORK) + return ip->i_cowfp; + else if (state & BMAP_ATTRFORK) + return &ip->i_af; + return &ip->i_df; +} + +/* + * Initialize an inode's copy-on-write fork. + */ +void +xfs_ifork_init_cow( + struct xfs_inode *ip) +{ + if (ip->i_cowfp) + return; + + ip->i_cowfp = kmem_cache_zalloc(xfs_ifork_cache, + GFP_NOFS | __GFP_NOFAIL); + ip->i_cowfp->if_format = XFS_DINODE_FMT_EXTENTS; +} + +/* Verify the inline contents of the data fork of an inode. */ +int +xfs_ifork_verify_local_data( + struct xfs_inode *ip) +{ + xfs_failaddr_t fa = NULL; + + switch (VFS_I(ip)->i_mode & S_IFMT) { + case S_IFDIR: + fa = xfs_dir2_sf_verify(ip); + break; + case S_IFLNK: + fa = xfs_symlink_shortform_verify(ip); + break; + default: + break; + } + + if (fa) { + xfs_inode_verifier_error(ip, -EFSCORRUPTED, "data fork", + ip->i_df.if_u1.if_data, ip->i_df.if_bytes, fa); + return -EFSCORRUPTED; + } + + return 0; +} + +/* Verify the inline contents of the attr fork of an inode. */ +int +xfs_ifork_verify_local_attr( + struct xfs_inode *ip) +{ + struct xfs_ifork *ifp = &ip->i_af; + xfs_failaddr_t fa; + + if (!xfs_inode_has_attr_fork(ip)) + fa = __this_address; + else + fa = xfs_attr_shortform_verify(ip); + + if (fa) { + xfs_inode_verifier_error(ip, -EFSCORRUPTED, "attr fork", + ifp->if_u1.if_data, ifp->if_bytes, fa); + return -EFSCORRUPTED; + } + + return 0; +} + +int +xfs_iext_count_may_overflow( + struct xfs_inode *ip, + int whichfork, + int nr_to_add) +{ + struct xfs_ifork *ifp = xfs_ifork_ptr(ip, whichfork); + uint64_t max_exts; + uint64_t nr_exts; + + if (whichfork == XFS_COW_FORK) + return 0; + + max_exts = xfs_iext_max_nextents(xfs_inode_has_large_extent_counts(ip), + whichfork); + + if (XFS_TEST_ERROR(false, ip->i_mount, XFS_ERRTAG_REDUCE_MAX_IEXTENTS)) + max_exts = 10; + + nr_exts = ifp->if_nextents + nr_to_add; + if (nr_exts < ifp->if_nextents || nr_exts > max_exts) + return -EFBIG; + + return 0; +} + +/* + * Upgrade this inode's extent counter fields to be able to handle a potential + * increase in the extent count by nr_to_add. Normally this is the same + * quantity that caused xfs_iext_count_may_overflow() to return -EFBIG. + */ +int +xfs_iext_count_upgrade( + struct xfs_trans *tp, + struct xfs_inode *ip, + uint nr_to_add) +{ + ASSERT(nr_to_add <= XFS_MAX_EXTCNT_UPGRADE_NR); + + if (!xfs_has_large_extent_counts(ip->i_mount) || + xfs_inode_has_large_extent_counts(ip) || + XFS_TEST_ERROR(false, ip->i_mount, XFS_ERRTAG_REDUCE_MAX_IEXTENTS)) + return -EFBIG; + + ip->i_diflags2 |= XFS_DIFLAG2_NREXT64; + xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); + + return 0; +} |