From ace9429bb58fd418f0c81d4c2835699bddf6bde6 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Thu, 11 Apr 2024 10:27:49 +0200 Subject: Adding upstream version 6.6.15. Signed-off-by: Daniel Baumann --- fs/xfs/xfs_export.c | 251 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 251 insertions(+) create mode 100644 fs/xfs/xfs_export.c (limited to 'fs/xfs/xfs_export.c') diff --git a/fs/xfs/xfs_export.c b/fs/xfs/xfs_export.c new file mode 100644 index 000000000..7cd09c3a8 --- /dev/null +++ b/fs/xfs/xfs_export.c @@ -0,0 +1,251 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2004-2005 Silicon Graphics, Inc. + * All Rights Reserved. + */ +#include "xfs.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_dir2.h" +#include "xfs_export.h" +#include "xfs_inode.h" +#include "xfs_trans.h" +#include "xfs_inode_item.h" +#include "xfs_icache.h" +#include "xfs_pnfs.h" + +/* + * Note that we only accept fileids which are long enough rather than allow + * the parent generation number to default to zero. XFS considers zero a + * valid generation number not an invalid/wildcard value. + */ +static int xfs_fileid_length(int fileid_type) +{ + switch (fileid_type) { + case FILEID_INO32_GEN: + return 2; + case FILEID_INO32_GEN_PARENT: + return 4; + case FILEID_INO32_GEN | XFS_FILEID_TYPE_64FLAG: + return 3; + case FILEID_INO32_GEN_PARENT | XFS_FILEID_TYPE_64FLAG: + return 6; + } + return FILEID_INVALID; +} + +STATIC int +xfs_fs_encode_fh( + struct inode *inode, + __u32 *fh, + int *max_len, + struct inode *parent) +{ + struct xfs_mount *mp = XFS_M(inode->i_sb); + struct fid *fid = (struct fid *)fh; + struct xfs_fid64 *fid64 = (struct xfs_fid64 *)fh; + int fileid_type; + int len; + + /* Directories don't need their parent encoded, they have ".." */ + if (!parent) + fileid_type = FILEID_INO32_GEN; + else + fileid_type = FILEID_INO32_GEN_PARENT; + + /* + * If the filesystem may contain 64bit inode numbers, we need + * to use larger file handles that can represent them. + * + * While we only allocate inodes that do not fit into 32 bits any + * large enough filesystem may contain them, thus the slightly + * confusing looking conditional below. + */ + if (!xfs_has_small_inums(mp) || xfs_is_inode32(mp)) + fileid_type |= XFS_FILEID_TYPE_64FLAG; + + /* + * Only encode if there is enough space given. In practice + * this means we can't export a filesystem with 64bit inodes + * over NFSv2 with the subtree_check export option; the other + * seven combinations work. The real answer is "don't use v2". + */ + len = xfs_fileid_length(fileid_type); + if (*max_len < len) { + *max_len = len; + return FILEID_INVALID; + } + *max_len = len; + + switch (fileid_type) { + case FILEID_INO32_GEN_PARENT: + fid->i32.parent_ino = XFS_I(parent)->i_ino; + fid->i32.parent_gen = parent->i_generation; + fallthrough; + case FILEID_INO32_GEN: + fid->i32.ino = XFS_I(inode)->i_ino; + fid->i32.gen = inode->i_generation; + break; + case FILEID_INO32_GEN_PARENT | XFS_FILEID_TYPE_64FLAG: + fid64->parent_ino = XFS_I(parent)->i_ino; + fid64->parent_gen = parent->i_generation; + fallthrough; + case FILEID_INO32_GEN | XFS_FILEID_TYPE_64FLAG: + fid64->ino = XFS_I(inode)->i_ino; + fid64->gen = inode->i_generation; + break; + } + + return fileid_type; +} + +STATIC struct inode * +xfs_nfs_get_inode( + struct super_block *sb, + u64 ino, + u32 generation) +{ + xfs_mount_t *mp = XFS_M(sb); + xfs_inode_t *ip; + int error; + + /* + * NFS can sometimes send requests for ino 0. Fail them gracefully. + */ + if (ino == 0) + return ERR_PTR(-ESTALE); + + /* + * The XFS_IGET_UNTRUSTED means that an invalid inode number is just + * fine and not an indication of a corrupted filesystem as clients can + * send invalid file handles and we have to handle it gracefully.. + */ + error = xfs_iget(mp, NULL, ino, XFS_IGET_UNTRUSTED, 0, &ip); + if (error) { + + /* + * EINVAL means the inode cluster doesn't exist anymore. + * EFSCORRUPTED means the metadata pointing to the inode cluster + * or the inode cluster itself is corrupt. This implies the + * filehandle is stale, so we should translate it here. + * We don't use ESTALE directly down the chain to not + * confuse applications using bulkstat that expect EINVAL. + */ + switch (error) { + case -EINVAL: + case -ENOENT: + case -EFSCORRUPTED: + error = -ESTALE; + break; + default: + break; + } + return ERR_PTR(error); + } + + /* + * Reload the incore unlinked list to avoid failure in inodegc. + * Use an unlocked check here because unrecovered unlinked inodes + * should be somewhat rare. + */ + if (xfs_inode_unlinked_incomplete(ip)) { + error = xfs_inode_reload_unlinked(ip); + if (error) { + xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE); + xfs_irele(ip); + return ERR_PTR(error); + } + } + + if (VFS_I(ip)->i_generation != generation) { + xfs_irele(ip); + return ERR_PTR(-ESTALE); + } + + return VFS_I(ip); +} + +STATIC struct dentry * +xfs_fs_fh_to_dentry(struct super_block *sb, struct fid *fid, + int fh_len, int fileid_type) +{ + struct xfs_fid64 *fid64 = (struct xfs_fid64 *)fid; + struct inode *inode = NULL; + + if (fh_len < xfs_fileid_length(fileid_type)) + return NULL; + + switch (fileid_type) { + case FILEID_INO32_GEN_PARENT: + case FILEID_INO32_GEN: + inode = xfs_nfs_get_inode(sb, fid->i32.ino, fid->i32.gen); + break; + case FILEID_INO32_GEN_PARENT | XFS_FILEID_TYPE_64FLAG: + case FILEID_INO32_GEN | XFS_FILEID_TYPE_64FLAG: + inode = xfs_nfs_get_inode(sb, fid64->ino, fid64->gen); + break; + } + + return d_obtain_alias(inode); +} + +STATIC struct dentry * +xfs_fs_fh_to_parent(struct super_block *sb, struct fid *fid, + int fh_len, int fileid_type) +{ + struct xfs_fid64 *fid64 = (struct xfs_fid64 *)fid; + struct inode *inode = NULL; + + if (fh_len < xfs_fileid_length(fileid_type)) + return NULL; + + switch (fileid_type) { + case FILEID_INO32_GEN_PARENT: + inode = xfs_nfs_get_inode(sb, fid->i32.parent_ino, + fid->i32.parent_gen); + break; + case FILEID_INO32_GEN_PARENT | XFS_FILEID_TYPE_64FLAG: + inode = xfs_nfs_get_inode(sb, fid64->parent_ino, + fid64->parent_gen); + break; + } + + return d_obtain_alias(inode); +} + +STATIC struct dentry * +xfs_fs_get_parent( + struct dentry *child) +{ + int error; + struct xfs_inode *cip; + + error = xfs_lookup(XFS_I(d_inode(child)), &xfs_name_dotdot, &cip, NULL); + if (unlikely(error)) + return ERR_PTR(error); + + return d_obtain_alias(VFS_I(cip)); +} + +STATIC int +xfs_fs_nfs_commit_metadata( + struct inode *inode) +{ + return xfs_log_force_inode(XFS_I(inode)); +} + +const struct export_operations xfs_export_operations = { + .encode_fh = xfs_fs_encode_fh, + .fh_to_dentry = xfs_fs_fh_to_dentry, + .fh_to_parent = xfs_fs_fh_to_parent, + .get_parent = xfs_fs_get_parent, + .commit_metadata = xfs_fs_nfs_commit_metadata, +#ifdef CONFIG_EXPORTFS_BLOCK_OPS + .get_uuid = xfs_fs_get_uuid, + .map_blocks = xfs_fs_map_blocks, + .commit_blocks = xfs_fs_commit_blocks, +#endif +}; -- cgit v1.2.3