| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * linux/drivers/staging/erofs/inode.c |
| * |
| * Copyright (C) 2017-2018 HUAWEI, Inc. |
| * http://www.huawei.com/ |
| * Created by Gao Xiang <gaoxiang25@huawei.com> |
| * |
| * This file is subject to the terms and conditions of the GNU General Public |
| * License. See the file COPYING in the main directory of the Linux |
| * distribution for more details. |
| */ |
| #include "xattr.h" |
| |
| #include <trace/events/erofs.h> |
| |
| /* no locking */ |
| static int read_inode(struct inode *inode, void *data) |
| { |
| struct erofs_vnode *vi = EROFS_V(inode); |
| struct erofs_inode_v1 *v1 = data; |
| const unsigned int advise = le16_to_cpu(v1->i_advise); |
| |
| vi->data_mapping_mode = __inode_data_mapping(advise); |
| |
| if (unlikely(vi->data_mapping_mode >= EROFS_INODE_LAYOUT_MAX)) { |
| errln("unknown data mapping mode %u of nid %llu", |
| vi->data_mapping_mode, vi->nid); |
| DBG_BUGON(1); |
| return -EIO; |
| } |
| |
| if (__inode_version(advise) == EROFS_INODE_LAYOUT_V2) { |
| struct erofs_inode_v2 *v2 = data; |
| |
| vi->inode_isize = sizeof(struct erofs_inode_v2); |
| vi->xattr_isize = ondisk_xattr_ibody_size(v2->i_xattr_icount); |
| |
| inode->i_mode = le16_to_cpu(v2->i_mode); |
| if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || |
| S_ISLNK(inode->i_mode)) { |
| vi->raw_blkaddr = le32_to_cpu(v2->i_u.raw_blkaddr); |
| } else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) { |
| inode->i_rdev = |
| new_decode_dev(le32_to_cpu(v2->i_u.rdev)); |
| } else if (S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) { |
| inode->i_rdev = 0; |
| } else { |
| return -EIO; |
| } |
| |
| i_uid_write(inode, le32_to_cpu(v2->i_uid)); |
| i_gid_write(inode, le32_to_cpu(v2->i_gid)); |
| set_nlink(inode, le32_to_cpu(v2->i_nlink)); |
| |
| /* ns timestamp */ |
| inode->i_mtime.tv_sec = inode->i_ctime.tv_sec = |
| le64_to_cpu(v2->i_ctime); |
| inode->i_mtime.tv_nsec = inode->i_ctime.tv_nsec = |
| le32_to_cpu(v2->i_ctime_nsec); |
| |
| inode->i_size = le64_to_cpu(v2->i_size); |
| } else if (__inode_version(advise) == EROFS_INODE_LAYOUT_V1) { |
| struct erofs_sb_info *sbi = EROFS_SB(inode->i_sb); |
| |
| vi->inode_isize = sizeof(struct erofs_inode_v1); |
| vi->xattr_isize = ondisk_xattr_ibody_size(v1->i_xattr_icount); |
| |
| inode->i_mode = le16_to_cpu(v1->i_mode); |
| if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || |
| S_ISLNK(inode->i_mode)) { |
| vi->raw_blkaddr = le32_to_cpu(v1->i_u.raw_blkaddr); |
| } else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) { |
| inode->i_rdev = |
| new_decode_dev(le32_to_cpu(v1->i_u.rdev)); |
| } else if (S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) { |
| inode->i_rdev = 0; |
| } else { |
| return -EIO; |
| } |
| |
| i_uid_write(inode, le16_to_cpu(v1->i_uid)); |
| i_gid_write(inode, le16_to_cpu(v1->i_gid)); |
| set_nlink(inode, le16_to_cpu(v1->i_nlink)); |
| |
| /* use build time to derive all file time */ |
| inode->i_mtime.tv_sec = inode->i_ctime.tv_sec = |
| sbi->build_time; |
| inode->i_mtime.tv_nsec = inode->i_ctime.tv_nsec = |
| sbi->build_time_nsec; |
| |
| inode->i_size = le32_to_cpu(v1->i_size); |
| } else { |
| errln("unsupported on-disk inode version %u of nid %llu", |
| __inode_version(advise), vi->nid); |
| DBG_BUGON(1); |
| return -EIO; |
| } |
| |
| /* measure inode.i_blocks as the generic filesystem */ |
| inode->i_blocks = ((inode->i_size - 1) >> 9) + 1; |
| return 0; |
| } |
| |
| /* |
| * try_lock can be required since locking order is: |
| * file data(fs_inode) |
| * meta(bd_inode) |
| * but the majority of the callers is "iget", |
| * in that case we are pretty sure no deadlock since |
| * no data operations exist. However I tend to |
| * try_lock since it takes no much overhead and |
| * will success immediately. |
| */ |
| static int fill_inline_data(struct inode *inode, void *data, |
| unsigned int m_pofs) |
| { |
| struct erofs_vnode *vi = EROFS_V(inode); |
| struct erofs_sb_info *sbi = EROFS_I_SB(inode); |
| int mode = vi->data_mapping_mode; |
| |
| DBG_BUGON(mode >= EROFS_INODE_LAYOUT_MAX); |
| |
| /* should be inode inline C */ |
| if (mode != EROFS_INODE_LAYOUT_INLINE) |
| return 0; |
| |
| /* fast symlink (following ext4) */ |
| if (S_ISLNK(inode->i_mode) && inode->i_size < PAGE_SIZE) { |
| char *lnk = erofs_kmalloc(sbi, inode->i_size + 1, GFP_KERNEL); |
| |
| if (unlikely(lnk == NULL)) |
| return -ENOMEM; |
| |
| m_pofs += vi->inode_isize + vi->xattr_isize; |
| |
| /* inline symlink data shouldn't across page boundary as well */ |
| if (unlikely(m_pofs + inode->i_size > PAGE_SIZE)) { |
| DBG_BUGON(1); |
| kfree(lnk); |
| return -EIO; |
| } |
| |
| /* get in-page inline data */ |
| memcpy(lnk, data + m_pofs, inode->i_size); |
| lnk[inode->i_size] = '\0'; |
| |
| inode->i_link = lnk; |
| set_inode_fast_symlink(inode); |
| } |
| return -EAGAIN; |
| } |
| |
| static int fill_inode(struct inode *inode, int isdir) |
| { |
| struct erofs_sb_info *sbi = EROFS_SB(inode->i_sb); |
| struct erofs_vnode *vi = EROFS_V(inode); |
| struct page *page; |
| void *data; |
| int err; |
| erofs_blk_t blkaddr; |
| unsigned int ofs; |
| |
| trace_erofs_fill_inode(inode, isdir); |
| |
| blkaddr = erofs_blknr(iloc(sbi, vi->nid)); |
| ofs = erofs_blkoff(iloc(sbi, vi->nid)); |
| |
| debugln("%s, reading inode nid %llu at %u of blkaddr %u", |
| __func__, vi->nid, ofs, blkaddr); |
| |
| page = erofs_get_meta_page(inode->i_sb, blkaddr, isdir); |
| |
| if (IS_ERR(page)) { |
| errln("failed to get inode (nid: %llu) page, err %ld", |
| vi->nid, PTR_ERR(page)); |
| return PTR_ERR(page); |
| } |
| |
| DBG_BUGON(!PageUptodate(page)); |
| data = page_address(page); |
| |
| err = read_inode(inode, data + ofs); |
| if (!err) { |
| /* setup the new inode */ |
| if (S_ISREG(inode->i_mode)) { |
| inode->i_op = &erofs_generic_iops; |
| inode->i_fop = &generic_ro_fops; |
| } else if (S_ISDIR(inode->i_mode)) { |
| inode->i_op = &erofs_dir_iops; |
| inode->i_fop = &erofs_dir_fops; |
| } else if (S_ISLNK(inode->i_mode)) { |
| /* by default, page_get_link is used for symlink */ |
| inode->i_op = &erofs_symlink_iops; |
| inode_nohighmem(inode); |
| } else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) || |
| S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) { |
| inode->i_op = &erofs_generic_iops; |
| init_special_inode(inode, inode->i_mode, inode->i_rdev); |
| } else { |
| err = -EIO; |
| goto out_unlock; |
| } |
| |
| if (is_inode_layout_compression(inode)) { |
| #ifdef CONFIG_EROFS_FS_ZIP |
| inode->i_mapping->a_ops = |
| &z_erofs_vle_normalaccess_aops; |
| #else |
| err = -ENOTSUPP; |
| #endif |
| goto out_unlock; |
| } |
| |
| inode->i_mapping->a_ops = &erofs_raw_access_aops; |
| |
| /* fill last page if inline data is available */ |
| fill_inline_data(inode, data, ofs); |
| } |
| |
| 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. |
| */ |
| #if BITS_PER_LONG == 32 |
| static int erofs_ilookup_test_actor(struct inode *inode, void *opaque) |
| { |
| const erofs_nid_t nid = *(erofs_nid_t *)opaque; |
| |
| return EROFS_V(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; |
| } |
| #endif |
| |
| static inline struct inode *erofs_iget_locked(struct super_block *sb, |
| erofs_nid_t nid) |
| { |
| const unsigned long hashval = erofs_inode_hash(nid); |
| |
| #if BITS_PER_LONG >= 64 |
| /* it is safe to use iget_locked for >= 64-bit platform */ |
| return iget_locked(sb, hashval); |
| #else |
| return iget5_locked(sb, hashval, erofs_ilookup_test_actor, |
| erofs_iget_set_actor, &nid); |
| #endif |
| } |
| |
| struct inode *erofs_iget(struct super_block *sb, |
| erofs_nid_t nid, bool isdir) |
| { |
| struct inode *inode = erofs_iget_locked(sb, nid); |
| |
| if (unlikely(inode == NULL)) |
| return ERR_PTR(-ENOMEM); |
| |
| if (inode->i_state & I_NEW) { |
| int err; |
| struct erofs_vnode *vi = EROFS_V(inode); |
| vi->nid = nid; |
| |
| err = fill_inode(inode, isdir); |
| if (likely(!err)) |
| unlock_new_inode(inode); |
| else { |
| iget_failed(inode); |
| inode = ERR_PTR(err); |
| } |
| } |
| return inode; |
| } |
| |
| const struct inode_operations erofs_generic_iops = { |
| #ifdef CONFIG_EROFS_FS_XATTR |
| .listxattr = erofs_listxattr, |
| #endif |
| .get_acl = erofs_get_acl, |
| }; |
| |
| const struct inode_operations erofs_symlink_iops = { |
| .get_link = page_get_link, |
| #ifdef CONFIG_EROFS_FS_XATTR |
| .listxattr = erofs_listxattr, |
| #endif |
| .get_acl = erofs_get_acl, |
| }; |
| |
| const struct inode_operations erofs_fast_symlink_iops = { |
| .get_link = simple_get_link, |
| #ifdef CONFIG_EROFS_FS_XATTR |
| .listxattr = erofs_listxattr, |
| #endif |
| .get_acl = erofs_get_acl, |
| }; |
| |