#include "xattr.h"
#include <linux/compat.h>
#include <trace/events/erofs.h>
static int erofs_fill_symlink(struct inode *inode, void *bptr, unsigned int ofs)
{
struct erofs_inode *vi = EROFS_I(inode);
char *link;
loff_t end;
ofs += vi->xattr_isize;
if (vi->datalayout == EROFS_INODE_FLAT_INLINE &&
!check_add_overflow(ofs, inode->i_size, &end) &&
end <= i_blocksize(inode)) {
link = kmemdup_nul(bptr + ofs, inode->i_size, GFP_KERNEL);
if (!link)
return -ENOMEM;
if (unlikely(!inode->i_size || strlen(link) != inode->i_size)) {
erofs_err(inode->i_sb, "invalid fast symlink size %llu @ nid %llu",
inode->i_size | 0ULL, vi->nid);
kfree(link);
return -EFSCORRUPTED;
}
inode_set_cached_link(inode, link, inode->i_size);
}
return 0;
}
static int erofs_read_inode(struct inode *inode)
{
struct super_block *sb = inode->i_sb;
erofs_blk_t blkaddr = erofs_blknr(sb, erofs_iloc(inode));
unsigned int ofs = erofs_blkoff(sb, erofs_iloc(inode));
bool in_mbox = erofs_inode_in_metabox(inode);
struct erofs_buf buf = __EROFS_BUF_INITIALIZER;
struct erofs_sb_info *sbi = EROFS_SB(sb);
erofs_blk_t addrmask = BIT_ULL(48) - 1;
struct erofs_inode *vi = EROFS_I(inode);
struct erofs_inode_extended *die, copied;
struct erofs_inode_compact *dic;
unsigned int ifmt;
void *ptr;
int err = 0;
ptr = erofs_read_metabuf(&buf, sb, erofs_pos(sb, blkaddr), in_mbox);
if (IS_ERR(ptr)) {
err = PTR_ERR(ptr);
erofs_err(sb, "failed to read inode meta block (nid: %llu): %d",
vi->nid, err);
goto err_out;
}
dic = ptr + ofs;
ifmt = le16_to_cpu(dic->i_format);
if (ifmt & ~EROFS_I_ALL) {
erofs_err(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(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);
if (ofs + vi->inode_isize <= sb->s_blocksize) {
ofs += vi->inode_isize;
die = (struct erofs_inode_extended *)dic;
copied.i_u = die->i_u;
copied.i_nb = die->i_nb;
} else {
const unsigned int gotten = sb->s_blocksize - ofs;
memcpy(&copied, dic, gotten);
ptr = erofs_read_metabuf(&buf, sb,
erofs_pos(sb, blkaddr + 1), in_mbox);
if (IS_ERR(ptr)) {
err = PTR_ERR(ptr);
erofs_err(sb, "failed to read inode payload block (nid: %llu): %d",
vi->nid, err);
goto err_out;
}
ofs = vi->inode_isize - gotten;
memcpy((u8 *)&copied + gotten, ptr, ofs);
die = &copied;
}
vi->xattr_isize = erofs_xattr_ibody_size(die->i_xattr_icount);
inode->i_mode = le16_to_cpu(die->i_mode);
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));
inode_set_mtime(inode, le64_to_cpu(die->i_mtime),
le32_to_cpu(die->i_mtime_nsec));
inode->i_size = le64_to_cpu(die->i_size);
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);
copied.i_u = dic->i_u;
i_uid_write(inode, le16_to_cpu(dic->i_uid));
i_gid_write(inode, le16_to_cpu(dic->i_gid));
if (!S_ISDIR(inode->i_mode) &&
((ifmt >> EROFS_I_NLINK_1_BIT) & 1)) {
set_nlink(inode, 1);
copied.i_nb = dic->i_nb;
} else {
set_nlink(inode, le16_to_cpu(dic->i_nb.nlink));
copied.i_nb.startblk_hi = 0;
addrmask = BIT_ULL(32) - 1;
}
inode_set_mtime(inode, sbi->epoch + le32_to_cpu(dic->i_mtime),
sbi->fixed_nsec);
inode->i_size = le32_to_cpu(dic->i_size);
break;
default:
erofs_err(sb, "unsupported on-disk inode version %u of nid %llu",
erofs_inode_version(ifmt), vi->nid);
err = -EOPNOTSUPP;
goto err_out;
}
if (unlikely(inode->i_size < 0)) {
erofs_err(sb, "negative i_size @ nid %llu", vi->nid);
err = -EFSCORRUPTED;
goto err_out;
}
if (IS_ENABLED(CONFIG_EROFS_FS_POSIX_ACL) &&
erofs_inode_has_noacl(inode, ptr, ofs))
cache_no_acl(inode);
switch (inode->i_mode & S_IFMT) {
case S_IFDIR:
vi->dot_omitted = (ifmt >> EROFS_I_DOT_OMITTED_BIT) & 1;
fallthrough;
case S_IFREG:
case S_IFLNK:
vi->startblk = le32_to_cpu(copied.i_u.startblk_lo) |
((u64)le16_to_cpu(copied.i_nb.startblk_hi) << 32);
if (vi->datalayout == EROFS_INODE_FLAT_PLAIN &&
!((vi->startblk ^ EROFS_NULL_ADDR) & addrmask))
vi->startblk = EROFS_NULL_ADDR;
if(S_ISLNK(inode->i_mode)) {
err = erofs_fill_symlink(inode, ptr, ofs);
if (err)
goto err_out;
}
break;
case S_IFCHR:
case S_IFBLK:
inode->i_rdev = new_decode_dev(le32_to_cpu(copied.i_u.rdev));
break;
case S_IFIFO:
case S_IFSOCK:
inode->i_rdev = 0;
break;
default:
erofs_err(sb, "bogus i_mode (%o) @ nid %llu", inode->i_mode,
vi->nid);
err = -EFSCORRUPTED;
goto err_out;
}
if (!erofs_inode_is_data_compressed(vi->datalayout)) {
inode->i_blocks = round_up(inode->i_size, sb->s_blocksize) >> 9;
} else if (!IS_ENABLED(CONFIG_EROFS_FS_ZIP) || !sbi->available_compr_algs) {
erofs_err(sb, "compressed inode (nid %llu) is invalid in a plain filesystem",
vi->nid);
err = -EFSCORRUPTED;
goto err_out;
} else {
inode->i_blocks = le32_to_cpu(copied.i_u.blocks_lo) <<
(sb->s_blocksize_bits - 9);
}
if (vi->datalayout == EROFS_INODE_CHUNK_BASED) {
vi->chunkformat = le16_to_cpu(copied.i_u.c.format);
if (vi->chunkformat & ~EROFS_CHUNK_FORMAT_ALL) {
erofs_err(sb, "unsupported chunk format %x of nid %llu",
vi->chunkformat, vi->nid);
err = -EOPNOTSUPP;
goto err_out;
}
vi->chunkbits = sb->s_blocksize_bits +
(vi->chunkformat & EROFS_CHUNK_FORMAT_BLKBITS_MASK);
}
inode_set_atime_to_ts(inode,
inode_set_ctime_to_ts(inode, inode_get_mtime(inode)));
inode->i_flags &= ~S_DAX;
if (test_opt(&sbi->opt, DAX_ALWAYS) && S_ISREG(inode->i_mode) &&
(vi->datalayout == EROFS_INODE_FLAT_PLAIN ||
vi->datalayout == EROFS_INODE_CHUNK_BASED))
inode->i_flags |= S_DAX;
err_out:
erofs_put_metabuf(&buf);
return err;
}
static int erofs_fill_inode(struct inode *inode)
{
const struct address_space_operations *aops;
int err;
trace_erofs_fill_inode(inode);
err = erofs_read_inode(inode);
if (err)
return err;
switch (inode->i_mode & S_IFMT) {
case S_IFREG:
inode->i_op = &erofs_generic_iops;
inode->i_fop = erofs_ishare_fill_inode(inode) ?
&erofs_ishare_fops : &erofs_file_fops;
break;
case S_IFDIR:
inode->i_op = &erofs_dir_iops;
inode->i_fop = &erofs_dir_fops;
inode_nohighmem(inode);
break;
case S_IFLNK:
if (inode->i_link)
inode->i_op = &erofs_fast_symlink_iops;
else
inode->i_op = &erofs_symlink_iops;
inode_nohighmem(inode);
break;
default:
inode->i_op = &erofs_generic_iops;
init_special_inode(inode, inode->i_mode, inode->i_rdev);
return 0;
}
mapping_set_large_folios(inode->i_mapping);
aops = erofs_get_aops(inode, false);
if (IS_ERR(aops))
return PTR_ERR(aops);
inode->i_mapping->a_ops = aops;
return 0;
}
static ino_t erofs_squash_ino(struct super_block *sb, erofs_nid_t nid)
{
u64 ino64 = erofs_nid_to_ino64(EROFS_SB(sb), nid);
if (sizeof(ino_t) < sizeof(erofs_nid_t))
ino64 ^= ino64 >> (sizeof(erofs_nid_t) - sizeof(ino_t)) * 8;
return (ino_t)ino64;
}
static int erofs_iget5_eq(struct inode *inode, void *opaque)
{
return EROFS_I(inode)->nid == *(erofs_nid_t *)opaque;
}
static int erofs_iget5_set(struct inode *inode, void *opaque)
{
const erofs_nid_t nid = *(erofs_nid_t *)opaque;
inode->i_ino = erofs_squash_ino(inode->i_sb, nid);
EROFS_I(inode)->nid = nid;
return 0;
}
struct inode *erofs_iget(struct super_block *sb, erofs_nid_t nid)
{
struct inode *inode;
inode = iget5_locked(sb, erofs_squash_ino(sb, nid), erofs_iget5_eq,
erofs_iget5_set, &nid);
if (!inode)
return ERR_PTR(-ENOMEM);
if (inode_state_read_once(inode) & I_NEW) {
int err = erofs_fill_inode(inode);
if (err) {
iget_failed(inode);
return ERR_PTR(err);
}
unlock_new_inode(inode);
}
return inode;
}
int erofs_getattr(struct mnt_idmap *idmap, const struct path *path,
struct kstat *stat, u32 request_mask,
unsigned int query_flags)
{
struct inode *const inode = d_inode(path->dentry);
struct block_device *bdev = inode->i_sb->s_bdev;
bool compressed =
erofs_inode_is_data_compressed(EROFS_I(inode)->datalayout);
if (compressed)
stat->attributes |= STATX_ATTR_COMPRESSED;
stat->attributes |= STATX_ATTR_IMMUTABLE;
stat->attributes_mask |= (STATX_ATTR_COMPRESSED |
STATX_ATTR_IMMUTABLE);
if ((request_mask & STATX_DIOALIGN) && S_ISREG(inode->i_mode)) {
stat->result_mask |= STATX_DIOALIGN;
if (bdev && !compressed) {
stat->dio_mem_align = bdev_dma_alignment(bdev) + 1;
stat->dio_offset_align = bdev_logical_block_size(bdev);
}
}
generic_fillattr(idmap, request_mask, inode, stat);
return 0;
}
static int erofs_ioctl_get_volume_label(struct inode *inode, void __user *arg)
{
struct erofs_sb_info *sbi = EROFS_I_SB(inode);
int ret;
if (!sbi->volume_name)
ret = clear_user(arg, 1);
else
ret = copy_to_user(arg, sbi->volume_name,
strlen(sbi->volume_name));
return ret ? -EFAULT : 0;
}
long erofs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
struct inode *inode = file_inode(filp);
void __user *argp = (void __user *)arg;
switch (cmd) {
case FS_IOC_GETFSLABEL:
return erofs_ioctl_get_volume_label(inode, argp);
default:
return -ENOTTY;
}
}
#ifdef CONFIG_COMPAT
long erofs_compat_ioctl(struct file *filp, unsigned int cmd,
unsigned long arg)
{
return erofs_ioctl(filp, cmd, (unsigned long)compat_ptr(arg));
}
#endif
const struct inode_operations erofs_generic_iops = {
.getattr = erofs_getattr,
.listxattr = erofs_listxattr,
.get_inode_acl = erofs_get_acl,
.fiemap = erofs_fiemap,
};
const struct inode_operations erofs_symlink_iops = {
.get_link = page_get_link,
.getattr = erofs_getattr,
.listxattr = erofs_listxattr,
.get_inode_acl = erofs_get_acl,
};
const struct inode_operations erofs_fast_symlink_iops = {
.get_link = simple_get_link,
.getattr = erofs_getattr,
.listxattr = erofs_listxattr,
.get_inode_acl = erofs_get_acl,
};
