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brintos / linux-shallow public Read only

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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Copyright (C) 2017-2018 HUAWEI, Inc.4 *             https://www.huawei.com/5 * Copyright (C) 2021, Alibaba Cloud6 */7#include "xattr.h"8#include <trace/events/erofs.h>9 10static int erofs_fill_symlink(struct inode *inode, void *kaddr,11			      unsigned int m_pofs)12{13	struct erofs_inode *vi = EROFS_I(inode);14	loff_t off;15 16	m_pofs += vi->xattr_isize;17	/* check if it cannot be handled with fast symlink scheme */18	if (vi->datalayout != EROFS_INODE_FLAT_INLINE ||19	    check_add_overflow(m_pofs, inode->i_size, &off) ||20	    off > i_blocksize(inode))21		return 0;22 23	inode->i_link = kmemdup_nul(kaddr + m_pofs, inode->i_size, GFP_KERNEL);24	return inode->i_link ? 0 : -ENOMEM;25}26 27static int erofs_read_inode(struct inode *inode)28{29	struct super_block *sb = inode->i_sb;30	struct erofs_sb_info *sbi = EROFS_SB(sb);31	struct erofs_inode *vi = EROFS_I(inode);32	const erofs_off_t inode_loc = erofs_iloc(inode);33	erofs_blk_t blkaddr, nblks = 0;34	void *kaddr;35	struct erofs_inode_compact *dic;36	struct erofs_inode_extended *die, *copied = NULL;37	union erofs_inode_i_u iu;38	struct erofs_buf buf = __EROFS_BUF_INITIALIZER;39	unsigned int ifmt, ofs;40	int err = 0;41 42	blkaddr = erofs_blknr(sb, inode_loc);43	ofs = erofs_blkoff(sb, inode_loc);44 45	kaddr = erofs_read_metabuf(&buf, sb, erofs_pos(sb, blkaddr), EROFS_KMAP);46	if (IS_ERR(kaddr)) {47		erofs_err(sb, "failed to get inode (nid: %llu) page, err %ld",48			  vi->nid, PTR_ERR(kaddr));49		return PTR_ERR(kaddr);50	}51 52	dic = kaddr + ofs;53	ifmt = le16_to_cpu(dic->i_format);54	if (ifmt & ~EROFS_I_ALL) {55		erofs_err(sb, "unsupported i_format %u of nid %llu",56			  ifmt, vi->nid);57		err = -EOPNOTSUPP;58		goto err_out;59	}60 61	vi->datalayout = erofs_inode_datalayout(ifmt);62	if (vi->datalayout >= EROFS_INODE_DATALAYOUT_MAX) {63		erofs_err(sb, "unsupported datalayout %u of nid %llu",64			  vi->datalayout, vi->nid);65		err = -EOPNOTSUPP;66		goto err_out;67	}68 69	switch (erofs_inode_version(ifmt)) {70	case EROFS_INODE_LAYOUT_EXTENDED:71		vi->inode_isize = sizeof(struct erofs_inode_extended);72		/* check if the extended inode acrosses block boundary */73		if (ofs + vi->inode_isize <= sb->s_blocksize) {74			ofs += vi->inode_isize;75			die = (struct erofs_inode_extended *)dic;76		} else {77			const unsigned int gotten = sb->s_blocksize - ofs;78 79			copied = kmalloc(vi->inode_isize, GFP_KERNEL);80			if (!copied) {81				err = -ENOMEM;82				goto err_out;83			}84			memcpy(copied, dic, gotten);85			kaddr = erofs_read_metabuf(&buf, sb, erofs_pos(sb, blkaddr + 1),86						   EROFS_KMAP);87			if (IS_ERR(kaddr)) {88				erofs_err(sb, "failed to get inode payload block (nid: %llu), err %ld",89					  vi->nid, PTR_ERR(kaddr));90				kfree(copied);91				return PTR_ERR(kaddr);92			}93			ofs = vi->inode_isize - gotten;94			memcpy((u8 *)copied + gotten, kaddr, ofs);95			die = copied;96		}97		vi->xattr_isize = erofs_xattr_ibody_size(die->i_xattr_icount);98 99		inode->i_mode = le16_to_cpu(die->i_mode);100		iu = die->i_u;101		i_uid_write(inode, le32_to_cpu(die->i_uid));102		i_gid_write(inode, le32_to_cpu(die->i_gid));103		set_nlink(inode, le32_to_cpu(die->i_nlink));104		/* each extended inode has its own timestamp */105		inode_set_ctime(inode, le64_to_cpu(die->i_mtime),106				le32_to_cpu(die->i_mtime_nsec));107 108		inode->i_size = le64_to_cpu(die->i_size);109		kfree(copied);110		break;111	case EROFS_INODE_LAYOUT_COMPACT:112		vi->inode_isize = sizeof(struct erofs_inode_compact);113		ofs += vi->inode_isize;114		vi->xattr_isize = erofs_xattr_ibody_size(dic->i_xattr_icount);115 116		inode->i_mode = le16_to_cpu(dic->i_mode);117		iu = dic->i_u;118		i_uid_write(inode, le16_to_cpu(dic->i_uid));119		i_gid_write(inode, le16_to_cpu(dic->i_gid));120		set_nlink(inode, le16_to_cpu(dic->i_nlink));121		/* use build time for compact inodes */122		inode_set_ctime(inode, sbi->build_time, sbi->build_time_nsec);123 124		inode->i_size = le32_to_cpu(dic->i_size);125		break;126	default:127		erofs_err(sb, "unsupported on-disk inode version %u of nid %llu",128			  erofs_inode_version(ifmt), vi->nid);129		err = -EOPNOTSUPP;130		goto err_out;131	}132 133	if (unlikely(inode->i_size < 0)) {134		erofs_err(sb, "negative i_size @ nid %llu", vi->nid);135		err = -EFSCORRUPTED;136		goto err_out;137	}138	switch (inode->i_mode & S_IFMT) {139	case S_IFREG:140	case S_IFDIR:141	case S_IFLNK:142		vi->raw_blkaddr = le32_to_cpu(iu.raw_blkaddr);143		if(S_ISLNK(inode->i_mode)) {144			err = erofs_fill_symlink(inode, kaddr, ofs);145			if (err)146				goto err_out;147		}148		break;149	case S_IFCHR:150	case S_IFBLK:151		inode->i_rdev = new_decode_dev(le32_to_cpu(iu.rdev));152		break;153	case S_IFIFO:154	case S_IFSOCK:155		inode->i_rdev = 0;156		break;157	default:158		erofs_err(sb, "bogus i_mode (%o) @ nid %llu", inode->i_mode,159			  vi->nid);160		err = -EFSCORRUPTED;161		goto err_out;162	}163 164	/* total blocks for compressed files */165	if (erofs_inode_is_data_compressed(vi->datalayout)) {166		nblks = le32_to_cpu(iu.compressed_blocks);167	} else if (vi->datalayout == EROFS_INODE_CHUNK_BASED) {168		/* fill chunked inode summary info */169		vi->chunkformat = le16_to_cpu(iu.c.format);170		if (vi->chunkformat & ~EROFS_CHUNK_FORMAT_ALL) {171			erofs_err(sb, "unsupported chunk format %x of nid %llu",172				  vi->chunkformat, vi->nid);173			err = -EOPNOTSUPP;174			goto err_out;175		}176		vi->chunkbits = sb->s_blocksize_bits +177			(vi->chunkformat & EROFS_CHUNK_FORMAT_BLKBITS_MASK);178	}179	inode_set_mtime_to_ts(inode,180			      inode_set_atime_to_ts(inode, inode_get_ctime(inode)));181 182	inode->i_flags &= ~S_DAX;183	if (test_opt(&sbi->opt, DAX_ALWAYS) && S_ISREG(inode->i_mode) &&184	    (vi->datalayout == EROFS_INODE_FLAT_PLAIN ||185	     vi->datalayout == EROFS_INODE_CHUNK_BASED))186		inode->i_flags |= S_DAX;187 188	if (!nblks)189		/* measure inode.i_blocks as generic filesystems */190		inode->i_blocks = round_up(inode->i_size, sb->s_blocksize) >> 9;191	else192		inode->i_blocks = nblks << (sb->s_blocksize_bits - 9);193err_out:194	DBG_BUGON(err);195	erofs_put_metabuf(&buf);196	return err;197}198 199static int erofs_fill_inode(struct inode *inode)200{201	struct erofs_inode *vi = EROFS_I(inode);202	int err;203 204	trace_erofs_fill_inode(inode);205 206	/* read inode base data from disk */207	err = erofs_read_inode(inode);208	if (err)209		return err;210 211	/* setup the new inode */212	switch (inode->i_mode & S_IFMT) {213	case S_IFREG:214		inode->i_op = &erofs_generic_iops;215		if (erofs_inode_is_data_compressed(vi->datalayout))216			inode->i_fop = &generic_ro_fops;217		else218			inode->i_fop = &erofs_file_fops;219		break;220	case S_IFDIR:221		inode->i_op = &erofs_dir_iops;222		inode->i_fop = &erofs_dir_fops;223		inode_nohighmem(inode);224		break;225	case S_IFLNK:226		if (inode->i_link)227			inode->i_op = &erofs_fast_symlink_iops;228		else229			inode->i_op = &erofs_symlink_iops;230		inode_nohighmem(inode);231		break;232	case S_IFCHR:233	case S_IFBLK:234	case S_IFIFO:235	case S_IFSOCK:236		inode->i_op = &erofs_generic_iops;237		init_special_inode(inode, inode->i_mode, inode->i_rdev);238		return 0;239	default:240		return -EFSCORRUPTED;241	}242 243	mapping_set_large_folios(inode->i_mapping);244	if (erofs_inode_is_data_compressed(vi->datalayout)) {245#ifdef CONFIG_EROFS_FS_ZIP246		DO_ONCE_LITE_IF(inode->i_blkbits != PAGE_SHIFT,247			  erofs_info, inode->i_sb,248			  "EXPERIMENTAL EROFS subpage compressed block support in use. Use at your own risk!");249		inode->i_mapping->a_ops = &z_erofs_aops;250#else251		err = -EOPNOTSUPP;252#endif253	} else {254		inode->i_mapping->a_ops = &erofs_aops;255#ifdef CONFIG_EROFS_FS_ONDEMAND256		if (erofs_is_fscache_mode(inode->i_sb))257			inode->i_mapping->a_ops = &erofs_fscache_access_aops;258#endif259#ifdef CONFIG_EROFS_FS_BACKED_BY_FILE260		if (erofs_is_fileio_mode(EROFS_SB(inode->i_sb)))261			inode->i_mapping->a_ops = &erofs_fileio_aops;262#endif263	}264 265	return err;266}267 268/*269 * ino_t is 32-bits on 32-bit arch. We have to squash the 64-bit value down270 * so that it will fit.271 */272static ino_t erofs_squash_ino(erofs_nid_t nid)273{274	ino_t ino = (ino_t)nid;275 276	if (sizeof(ino_t) < sizeof(erofs_nid_t))277		ino ^= nid >> (sizeof(erofs_nid_t) - sizeof(ino_t)) * 8;278	return ino;279}280 281static int erofs_iget5_eq(struct inode *inode, void *opaque)282{283	return EROFS_I(inode)->nid == *(erofs_nid_t *)opaque;284}285 286static int erofs_iget5_set(struct inode *inode, void *opaque)287{288	const erofs_nid_t nid = *(erofs_nid_t *)opaque;289 290	inode->i_ino = erofs_squash_ino(nid);291	EROFS_I(inode)->nid = nid;292	return 0;293}294 295struct inode *erofs_iget(struct super_block *sb, erofs_nid_t nid)296{297	struct inode *inode;298 299	inode = iget5_locked(sb, erofs_squash_ino(nid), erofs_iget5_eq,300			     erofs_iget5_set, &nid);301	if (!inode)302		return ERR_PTR(-ENOMEM);303 304	if (inode->i_state & I_NEW) {305		int err = erofs_fill_inode(inode);306 307		if (err) {308			iget_failed(inode);309			return ERR_PTR(err);310		}311		unlock_new_inode(inode);312	}313	return inode;314}315 316int erofs_getattr(struct mnt_idmap *idmap, const struct path *path,317		  struct kstat *stat, u32 request_mask,318		  unsigned int query_flags)319{320	struct inode *const inode = d_inode(path->dentry);321	bool compressed =322		erofs_inode_is_data_compressed(EROFS_I(inode)->datalayout);323 324	if (compressed)325		stat->attributes |= STATX_ATTR_COMPRESSED;326	stat->attributes |= STATX_ATTR_IMMUTABLE;327	stat->attributes_mask |= (STATX_ATTR_COMPRESSED |328				  STATX_ATTR_IMMUTABLE);329 330	/*331	 * Return the DIO alignment restrictions if requested.332	 *333	 * In EROFS, STATX_DIOALIGN is not supported in ondemand mode and334	 * compressed files, so in these cases we report no DIO support.335	 */336	if ((request_mask & STATX_DIOALIGN) && S_ISREG(inode->i_mode)) {337		stat->result_mask |= STATX_DIOALIGN;338		if (!erofs_is_fscache_mode(inode->i_sb) && !compressed) {339			stat->dio_mem_align =340				bdev_logical_block_size(inode->i_sb->s_bdev);341			stat->dio_offset_align = stat->dio_mem_align;342		}343	}344	generic_fillattr(idmap, request_mask, inode, stat);345	return 0;346}347 348const struct inode_operations erofs_generic_iops = {349	.getattr = erofs_getattr,350	.listxattr = erofs_listxattr,351	.get_inode_acl = erofs_get_acl,352	.fiemap = erofs_fiemap,353};354 355const struct inode_operations erofs_symlink_iops = {356	.get_link = page_get_link,357	.getattr = erofs_getattr,358	.listxattr = erofs_listxattr,359	.get_inode_acl = erofs_get_acl,360};361 362const struct inode_operations erofs_fast_symlink_iops = {363	.get_link = simple_get_link,364	.getattr = erofs_getattr,365	.listxattr = erofs_listxattr,366	.get_inode_acl = erofs_get_acl,367};368