| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * Copyright (C) 2017-2018 HUAWEI, Inc. |
| * https://www.huawei.com/ |
| */ |
| #include "xattr.h" |
| |
| #include <trace/events/erofs.h> |
| |
| /* |
| * if inode is successfully read, return its inode page (or sometimes |
| * the inode payload page if it's an extended inode) in order to fill |
| * inline data if possible. |
| */ |
| static struct page *erofs_read_inode(struct inode *inode, |
| unsigned int *ofs) |
| { |
| struct super_block *sb = inode->i_sb; |
| struct erofs_sb_info *sbi = EROFS_SB(sb); |
| struct erofs_inode *vi = EROFS_I(inode); |
| const erofs_off_t inode_loc = iloc(sbi, vi->nid); |
| |
| erofs_blk_t blkaddr, nblks = 0; |
| struct page *page; |
| struct erofs_inode_compact *dic; |
| struct erofs_inode_extended *die, *copied = NULL; |
| unsigned int ifmt; |
| int err; |
| |
| blkaddr = erofs_blknr(inode_loc); |
| *ofs = erofs_blkoff(inode_loc); |
| |
| erofs_dbg("%s, reading inode nid %llu at %u of blkaddr %u", |
| __func__, vi->nid, *ofs, blkaddr); |
| |
| page = erofs_get_meta_page(sb, blkaddr); |
| if (IS_ERR(page)) { |
| erofs_err(sb, "failed to get inode (nid: %llu) page, err %ld", |
| vi->nid, PTR_ERR(page)); |
| return page; |
| } |
| |
| dic = page_address(page) + *ofs; |
| ifmt = le16_to_cpu(dic->i_format); |
| |
| if (ifmt & ~EROFS_I_ALL) { |
| erofs_err(inode->i_sb, "unsupported i_format %u of nid %llu", |
| ifmt, vi->nid); |
| err = -EOPNOTSUPP; |
| goto err_out; |
| } |
| |
| vi->datalayout = erofs_inode_datalayout(ifmt); |
| if (vi->datalayout >= EROFS_INODE_DATALAYOUT_MAX) { |
| erofs_err(inode->i_sb, "unsupported datalayout %u of nid %llu", |
| vi->datalayout, vi->nid); |
| err = -EOPNOTSUPP; |
| goto err_out; |
| } |
| |
| switch (erofs_inode_version(ifmt)) { |
| case EROFS_INODE_LAYOUT_EXTENDED: |
| vi->inode_isize = sizeof(struct erofs_inode_extended); |
| /* check if the inode acrosses page boundary */ |
| if (*ofs + vi->inode_isize <= PAGE_SIZE) { |
| *ofs += vi->inode_isize; |
| die = (struct erofs_inode_extended *)dic; |
| } else { |
| const unsigned int gotten = PAGE_SIZE - *ofs; |
| |
| copied = kmalloc(vi->inode_isize, GFP_NOFS); |
| if (!copied) { |
| err = -ENOMEM; |
| goto err_out; |
| } |
| memcpy(copied, dic, gotten); |
| unlock_page(page); |
| put_page(page); |
| |
| page = erofs_get_meta_page(sb, blkaddr + 1); |
| if (IS_ERR(page)) { |
| erofs_err(sb, "failed to get inode payload page (nid: %llu), err %ld", |
| vi->nid, PTR_ERR(page)); |
| kfree(copied); |
| return page; |
| } |
| *ofs = vi->inode_isize - gotten; |
| memcpy((u8 *)copied + gotten, page_address(page), *ofs); |
| die = copied; |
| } |
| vi->xattr_isize = erofs_xattr_ibody_size(die->i_xattr_icount); |
| |
| inode->i_mode = le16_to_cpu(die->i_mode); |
| switch (inode->i_mode & S_IFMT) { |
| case S_IFREG: |
| case S_IFDIR: |
| case S_IFLNK: |
| vi->raw_blkaddr = le32_to_cpu(die->i_u.raw_blkaddr); |
| break; |
| case S_IFCHR: |
| case S_IFBLK: |
| inode->i_rdev = |
| new_decode_dev(le32_to_cpu(die->i_u.rdev)); |
| break; |
| case S_IFIFO: |
| case S_IFSOCK: |
| inode->i_rdev = 0; |
| break; |
| default: |
| goto bogusimode; |
| } |
| i_uid_write(inode, le32_to_cpu(die->i_uid)); |
| i_gid_write(inode, le32_to_cpu(die->i_gid)); |
| set_nlink(inode, le32_to_cpu(die->i_nlink)); |
| |
| /* extended inode has its own timestamp */ |
| inode->i_ctime.tv_sec = le64_to_cpu(die->i_ctime); |
| inode->i_ctime.tv_nsec = le32_to_cpu(die->i_ctime_nsec); |
| |
| inode->i_size = le64_to_cpu(die->i_size); |
| |
| /* total blocks for compressed files */ |
| if (erofs_inode_is_data_compressed(vi->datalayout)) |
| nblks = le32_to_cpu(die->i_u.compressed_blocks); |
| |
| kfree(copied); |
| break; |
| case EROFS_INODE_LAYOUT_COMPACT: |
| vi->inode_isize = sizeof(struct erofs_inode_compact); |
| *ofs += vi->inode_isize; |
| vi->xattr_isize = erofs_xattr_ibody_size(dic->i_xattr_icount); |
| |
| inode->i_mode = le16_to_cpu(dic->i_mode); |
| switch (inode->i_mode & S_IFMT) { |
| case S_IFREG: |
| case S_IFDIR: |
| case S_IFLNK: |
| vi->raw_blkaddr = le32_to_cpu(dic->i_u.raw_blkaddr); |
| break; |
| case S_IFCHR: |
| case S_IFBLK: |
| inode->i_rdev = |
| new_decode_dev(le32_to_cpu(dic->i_u.rdev)); |
| break; |
| case S_IFIFO: |
| case S_IFSOCK: |
| inode->i_rdev = 0; |
| break; |
| default: |
| goto bogusimode; |
| } |
| i_uid_write(inode, le16_to_cpu(dic->i_uid)); |
| i_gid_write(inode, le16_to_cpu(dic->i_gid)); |
| set_nlink(inode, le16_to_cpu(dic->i_nlink)); |
| |
| /* use build time for compact inodes */ |
| inode->i_ctime.tv_sec = sbi->build_time; |
| inode->i_ctime.tv_nsec = sbi->build_time_nsec; |
| |
| inode->i_size = le32_to_cpu(dic->i_size); |
| if (erofs_inode_is_data_compressed(vi->datalayout)) |
| nblks = le32_to_cpu(dic->i_u.compressed_blocks); |
| break; |
| default: |
| erofs_err(inode->i_sb, |
| "unsupported on-disk inode version %u of nid %llu", |
| erofs_inode_version(ifmt), vi->nid); |
| err = -EOPNOTSUPP; |
| goto err_out; |
| } |
| |
| inode->i_mtime.tv_sec = inode->i_ctime.tv_sec; |
| inode->i_atime.tv_sec = inode->i_ctime.tv_sec; |
| inode->i_mtime.tv_nsec = inode->i_ctime.tv_nsec; |
| inode->i_atime.tv_nsec = inode->i_ctime.tv_nsec; |
| |
| if (!nblks) |
| /* measure inode.i_blocks as generic filesystems */ |
| inode->i_blocks = roundup(inode->i_size, EROFS_BLKSIZ) >> 9; |
| else |
| inode->i_blocks = nblks << LOG_SECTORS_PER_BLOCK; |
| return page; |
| |
| bogusimode: |
| erofs_err(inode->i_sb, "bogus i_mode (%o) @ nid %llu", |
| inode->i_mode, vi->nid); |
| err = -EFSCORRUPTED; |
| err_out: |
| DBG_BUGON(1); |
| kfree(copied); |
| unlock_page(page); |
| put_page(page); |
| return ERR_PTR(err); |
| } |
| |
| static int erofs_fill_symlink(struct inode *inode, void *data, |
| unsigned int m_pofs) |
| { |
| struct erofs_inode *vi = EROFS_I(inode); |
| char *lnk; |
| |
| /* if it cannot be handled with fast symlink scheme */ |
| if (vi->datalayout != EROFS_INODE_FLAT_INLINE || |
| inode->i_size >= PAGE_SIZE) { |
| inode->i_op = &erofs_symlink_iops; |
| return 0; |
| } |
| |
| lnk = kmalloc(inode->i_size + 1, GFP_KERNEL); |
| if (!lnk) |
| return -ENOMEM; |
| |
| m_pofs += vi->xattr_isize; |
| /* inline symlink data shouldn't cross page boundary as well */ |
| if (m_pofs + inode->i_size > PAGE_SIZE) { |
| kfree(lnk); |
| erofs_err(inode->i_sb, |
| "inline data cross block boundary @ nid %llu", |
| vi->nid); |
| DBG_BUGON(1); |
| return -EFSCORRUPTED; |
| } |
| |
| memcpy(lnk, data + m_pofs, inode->i_size); |
| lnk[inode->i_size] = '\0'; |
| |
| inode->i_link = lnk; |
| inode->i_op = &erofs_fast_symlink_iops; |
| return 0; |
| } |
| |
| static int erofs_fill_inode(struct inode *inode, int isdir) |
| { |
| struct erofs_inode *vi = EROFS_I(inode); |
| struct page *page; |
| unsigned int ofs; |
| int err = 0; |
| |
| trace_erofs_fill_inode(inode, isdir); |
| |
| /* read inode base data from disk */ |
| page = erofs_read_inode(inode, &ofs); |
| if (IS_ERR(page)) |
| return PTR_ERR(page); |
| |
| /* setup the new inode */ |
| switch (inode->i_mode & S_IFMT) { |
| case S_IFREG: |
| inode->i_op = &erofs_generic_iops; |
| inode->i_fop = &generic_ro_fops; |
| break; |
| case S_IFDIR: |
| inode->i_op = &erofs_dir_iops; |
| inode->i_fop = &erofs_dir_fops; |
| break; |
| case S_IFLNK: |
| err = erofs_fill_symlink(inode, page_address(page), ofs); |
| if (err) |
| goto out_unlock; |
| inode_nohighmem(inode); |
| break; |
| case S_IFCHR: |
| case S_IFBLK: |
| case S_IFIFO: |
| case S_IFSOCK: |
| inode->i_op = &erofs_generic_iops; |
| init_special_inode(inode, inode->i_mode, inode->i_rdev); |
| goto out_unlock; |
| default: |
| err = -EFSCORRUPTED; |
| goto out_unlock; |
| } |
| |
| if (erofs_inode_is_data_compressed(vi->datalayout)) { |
| err = z_erofs_fill_inode(inode); |
| goto out_unlock; |
| } |
| inode->i_mapping->a_ops = &erofs_raw_access_aops; |
| |
| out_unlock: |
| unlock_page(page); |
| put_page(page); |
| return err; |
| } |
| |
| /* |
| * erofs nid is 64bits, but i_ino is 'unsigned long', therefore |
| * we should do more for 32-bit platform to find the right inode. |
| */ |
| static int erofs_ilookup_test_actor(struct inode *inode, void *opaque) |
| { |
| const erofs_nid_t nid = *(erofs_nid_t *)opaque; |
| |
| return EROFS_I(inode)->nid == nid; |
| } |
| |
| static int erofs_iget_set_actor(struct inode *inode, void *opaque) |
| { |
| const erofs_nid_t nid = *(erofs_nid_t *)opaque; |
| |
| inode->i_ino = erofs_inode_hash(nid); |
| return 0; |
| } |
| |
| static inline struct inode *erofs_iget_locked(struct super_block *sb, |
| erofs_nid_t nid) |
| { |
| const unsigned long hashval = erofs_inode_hash(nid); |
| |
| return iget5_locked(sb, hashval, erofs_ilookup_test_actor, |
| erofs_iget_set_actor, &nid); |
| } |
| |
| struct inode *erofs_iget(struct super_block *sb, |
| erofs_nid_t nid, |
| bool isdir) |
| { |
| struct inode *inode = erofs_iget_locked(sb, nid); |
| |
| if (!inode) |
| return ERR_PTR(-ENOMEM); |
| |
| if (inode->i_state & I_NEW) { |
| int err; |
| struct erofs_inode *vi = EROFS_I(inode); |
| |
| vi->nid = nid; |
| |
| err = erofs_fill_inode(inode, isdir); |
| if (!err) |
| unlock_new_inode(inode); |
| else { |
| iget_failed(inode); |
| inode = ERR_PTR(err); |
| } |
| } |
| return inode; |
| } |
| |
| int erofs_getattr(struct user_namespace *mnt_userns, const struct path *path, |
| struct kstat *stat, u32 request_mask, |
| unsigned int query_flags) |
| { |
| struct inode *const inode = d_inode(path->dentry); |
| |
| if (erofs_inode_is_data_compressed(EROFS_I(inode)->datalayout)) |
| stat->attributes |= STATX_ATTR_COMPRESSED; |
| |
| stat->attributes |= STATX_ATTR_IMMUTABLE; |
| stat->attributes_mask |= (STATX_ATTR_COMPRESSED | |
| STATX_ATTR_IMMUTABLE); |
| |
| generic_fillattr(&init_user_ns, inode, stat); |
| return 0; |
| } |
| |
| const struct inode_operations erofs_generic_iops = { |
| .getattr = erofs_getattr, |
| .listxattr = erofs_listxattr, |
| .get_acl = erofs_get_acl, |
| }; |
| |
| const struct inode_operations erofs_symlink_iops = { |
| .get_link = page_get_link, |
| .getattr = erofs_getattr, |
| .listxattr = erofs_listxattr, |
| .get_acl = erofs_get_acl, |
| }; |
| |
| const struct inode_operations erofs_fast_symlink_iops = { |
| .get_link = simple_get_link, |
| .getattr = erofs_getattr, |
| .listxattr = erofs_listxattr, |
| .get_acl = erofs_get_acl, |
| }; |