Re: [PATCH v4 5/6] f2fs: add f2fs_ioc_[get|set]_extra_attr

Jaegeuk Kim
2023-06-12T15:47:11Z

On 06/12, Sheng Yong wrote:
> This patch introduces two ioctls:
> * f2fs_ioc_get_extra_attr
> * f2fs_ioc_set_extra_attr
> to get or modify values in f2fs_inode's extra attribute area.

What'd be the main purpose of this new ioctl? Use-cases or examples?

>
> The argument of these two ioctls is `struct f2fs_extra_attr', which has
> three members:
> * field: indicates which field in extra attribute area is handled
> * attr: value or userspace pointer
> * attr_size: size of `attr'
>
> The `field' member could help extend functionality of these two ioctls
> without modify or add new interfaces, if more fields are added into
> extra attributes ares in the feture.
>
> Signed-off-by: Sheng Yong <shengyong@oppo.com>
> ---
> fs/f2fs/file.c | 205 ++++++++++++++++++++++++++++++++++++++
> include/uapi/linux/f2fs.h | 25 +++++
> 2 files changed, 230 insertions(+)
>
> diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
> index f8aa842b5d233..39d04f8f0bb6b 100644
> --- a/fs/f2fs/file.c
> +++ b/fs/f2fs/file.c
> @@ -4179,6 +4179,207 @@ static int f2fs_ioc_compress_file(struct file *filp)
> return ret;
> }
>
> +static bool extra_attr_fits_in_inode(struct inode *inode, int field)
> +{
> + struct f2fs_inode_info *fi = F2FS_I(inode);
> + struct f2fs_inode *ri;
> +
> + switch (field) {
> + case F2FS_EXTRA_ATTR_TOTAL_SIZE:
> + case F2FS_EXTRA_ATTR_ISIZE:
> + case F2FS_EXTRA_ATTR_INLINE_XATTR_SIZE:
> + return true;
> + case F2FS_EXTRA_ATTR_PROJID:
> + if (!F2FS_FITS_IN_INODE(ri, fi->i_extra_isize, i_projid))
> + return false;
> + return true;
> + case F2FS_EXTRA_ATTR_INODE_CHKSUM:
> + if (!F2FS_FITS_IN_INODE(ri, fi->i_extra_isize, i_inode_checksum))
> + return false;
> + return true;
> + case F2FS_EXTRA_ATTR_CRTIME:
> + if (!F2FS_FITS_IN_INODE(ri, fi->i_extra_isize, i_crtime))
> + return false;
> + return true;
> + case F2FS_EXTRA_ATTR_COMPR_BLOCKS:
> + case F2FS_EXTRA_ATTR_COMPR_OPTION:
> + if (!F2FS_FITS_IN_INODE(ri, fi->i_extra_isize, i_compr_blocks))
> + return false;
> + return true;
> + default:
> + BUG_ON(1);
> + return false;
> + }
> +}
> +
> +static int f2fs_ioc_get_extra_attr(struct file *filp, unsigned long arg)
> +{
> + struct inode *inode = file_inode(filp);
> + struct f2fs_inode_info *fi = F2FS_I(inode);
> + struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
> + struct f2fs_extra_attr attr;
> + u32 chksum;
> + int ret = 0;
> +
> + if (!f2fs_has_extra_attr(inode))
> + return -EOPNOTSUPP;
> +
> + if (copy_from_user(&attr, (void __user *)arg, sizeof(attr)))
> + return -EFAULT;
> +
> + if (attr.field >= F2FS_EXTRA_ATTR_MAX)
> + return -EINVAL;
> +
> + if (!extra_attr_fits_in_inode(inode, attr.field))
> + return -EOPNOTSUPP;
> +
> + switch (attr.field) {
> + case F2FS_EXTRA_ATTR_TOTAL_SIZE:
> + attr.attr = F2FS_TOTAL_EXTRA_ATTR_SIZE;
> + break;
> + case F2FS_EXTRA_ATTR_ISIZE:
> + attr.attr = fi->i_extra_isize;
> + break;
> + case F2FS_EXTRA_ATTR_INLINE_XATTR_SIZE:
> + if (!f2fs_has_inline_xattr(inode))
> + return -EOPNOTSUPP;
> + attr.attr = get_inline_xattr_addrs(inode);
> + break;
> + case F2FS_EXTRA_ATTR_PROJID:
> + if (!f2fs_sb_has_project_quota(F2FS_I_SB(inode)))
> + return -EOPNOTSUPP;
> + attr.attr = from_kprojid(&init_user_ns, fi->i_projid);
> + break;
> + case F2FS_EXTRA_ATTR_INODE_CHKSUM:
> + ret = f2fs_inode_chksum_get(sbi, inode, &chksum);
> + if (ret)
> + return ret;
> + attr.attr = chksum;
> + break;
> + case F2FS_EXTRA_ATTR_CRTIME:
> + if (!f2fs_sb_has_inode_crtime(sbi))
> + return -EOPNOTSUPP;
> + if (attr.attr_size == sizeof(struct timespec64)) {
> + if (put_timespec64(&fi->i_crtime,
> + (void __user *)(uintptr_t)attr.attr))
> + return -EFAULT;
> + } else if (attr.attr_size == sizeof(struct old_timespec32)) {
> + if (put_old_timespec32(&fi->i_crtime,
> + (void __user *)(uintptr_t)attr.attr))
> + return -EFAULT;
> + } else {
> + return -EINVAL;
> + }
> + break;
> + case F2FS_EXTRA_ATTR_COMPR_BLOCKS:
> + if (attr.attr_size != sizeof(__u64))
> + return -EINVAL;
> + ret = f2fs_get_compress_blocks(inode, &attr.attr);
> + break;
> + case F2FS_EXTRA_ATTR_COMPR_OPTION:
> + ret = f2fs_ioc_get_compress_option(filp, attr.attr);
> + break;
> + default:
> + return -EINVAL;
> + }
> +
> + if (ret < 0)
> + return ret;
> +
> + if (copy_to_user((void __user *)arg, &attr, sizeof(attr)))
> + return -EFAULT;
> +
> + return 0;
> +}
> +
> +static int f2fs_ioc_set_extra_attr(struct file *filp, unsigned long arg)
> +{
> + struct inode *inode = file_inode(filp);
> + struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
> + struct f2fs_extra_attr attr;
> + struct page *ipage;
> + void *inline_addr;
> + int ret;
> +
> + if (!f2fs_has_extra_attr(inode))
> + return -EOPNOTSUPP;
> +
> + if (copy_from_user(&attr, (void __user *)arg, sizeof(attr)))
> + return -EFAULT;
> +
> + if (attr.field >= F2FS_EXTRA_ATTR_MAX)
> + return -EINVAL;
> +
> + if (!extra_attr_fits_in_inode(inode, attr.field))
> + return -EOPNOTSUPP;
> +
> + switch (attr.field) {
> + case F2FS_EXTRA_ATTR_TOTAL_SIZE:
> + case F2FS_EXTRA_ATTR_ISIZE:
> + case F2FS_EXTRA_ATTR_PROJID:
> + case F2FS_EXTRA_ATTR_INODE_CHKSUM:
> + case F2FS_EXTRA_ATTR_CRTIME:
> + case F2FS_EXTRA_ATTR_COMPR_BLOCKS:
> + /* read only attribtues */
> + return -EOPNOTSUPP;
> + case F2FS_EXTRA_ATTR_INLINE_XATTR_SIZE:
> + if (!f2fs_sb_has_flexible_inline_xattr(sbi) ||
> + !f2fs_has_inline_xattr(inode))
> + return -EOPNOTSUPP;
> + if (attr.attr < MIN_INLINE_XATTR_SIZE ||
> + attr.attr > MAX_INLINE_XATTR_SIZE)
> + return -EINVAL;
> + inode_lock(inode);
> + f2fs_lock_op(sbi);
> + f2fs_down_write(&F2FS_I(inode)->i_xattr_sem);
> + if (i_size_read(inode) || F2FS_I(inode)->i_xattr_nid) {
> + /*
> + * it is not allowed to set this field if the inode
> + * has data or xattr node
> + */
> + ret = -EFBIG;
> + goto xattr_out_unlock;
> + }
> + ipage = f2fs_get_node_page(sbi, inode->i_ino);
> + if (IS_ERR(ipage)) {
> + ret = PTR_ERR(ipage);
> + goto xattr_out_unlock;
> + }
> + inline_addr = inline_xattr_addr(inode, ipage);
> + if (!IS_XATTR_LAST_ENTRY(XATTR_FIRST_ENTRY(inline_addr))) {
> + ret = -EFBIG;
> + } else {
> + struct f2fs_xattr_header *hdr;
> + struct f2fs_xattr_entry *ent;
> +
> + F2FS_I(inode)->i_inline_xattr_size = (int)attr.attr;
> + inline_addr = inline_xattr_addr(inode, ipage);
> + hdr = XATTR_HDR(inline_addr);
> + ent = XATTR_FIRST_ENTRY(inline_addr);
> + hdr->h_magic = cpu_to_le32(F2FS_XATTR_MAGIC);
> + hdr->h_refcount = cpu_to_le32(1);
> + memset(ent, 0, attr.attr - sizeof(*hdr));
> + set_page_dirty(ipage);
> + ret = 0;
> + }
> + f2fs_put_page(ipage, 1);
> +xattr_out_unlock:
> + f2fs_up_write(&F2FS_I(inode)->i_xattr_sem);
> + f2fs_unlock_op(sbi);
> + inode_unlock(inode);
> + if (!ret)
> + f2fs_balance_fs(sbi, true);
> + break;
> + case F2FS_EXTRA_ATTR_COMPR_OPTION:
> + ret = f2fs_ioc_set_compress_option(filp, attr.attr);
> + break;
> + default:
> + return -EINVAL;
> + }
> +
> + return ret;
> +}
> +
> static long __f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
> {
> switch (cmd) {
> @@ -4265,6 +4466,10 @@ static long __f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
> return f2fs_ioc_decompress_file(filp);
> case F2FS_IOC_COMPRESS_FILE:
> return f2fs_ioc_compress_file(filp);
> + case F2FS_IOC_GET_EXTRA_ATTR:
> + return f2fs_ioc_get_extra_attr(filp, arg);
> + case F2FS_IOC_SET_EXTRA_ATTR:
> + return f2fs_ioc_set_extra_attr(filp, arg);
> default:
> return -ENOTTY;
> }
> diff --git a/include/uapi/linux/f2fs.h b/include/uapi/linux/f2fs.h
> index 955d440be1046..2b53e90421bfc 100644
> --- a/include/uapi/linux/f2fs.h
> +++ b/include/uapi/linux/f2fs.h
> @@ -43,6 +43,10 @@
> #define F2FS_IOC_DECOMPRESS_FILE _IO(F2FS_IOCTL_MAGIC, 23)
> #define F2FS_IOC_COMPRESS_FILE _IO(F2FS_IOCTL_MAGIC, 24)
> #define F2FS_IOC_START_ATOMIC_REPLACE _IO(F2FS_IOCTL_MAGIC, 25)
> +#define F2FS_IOC_GET_EXTRA_ATTR _IOR(F2FS_IOCTL_MAGIC, 26, \
> + struct f2fs_extra_attr)
> +#define F2FS_IOC_SET_EXTRA_ATTR _IOW(F2FS_IOCTL_MAGIC, 27, \
> + struct f2fs_extra_attr)
>
> /*
> * should be same as XFS_IOC_GOINGDOWN.
> @@ -96,4 +100,25 @@ struct f2fs_comp_option {
> __u8 log_cluster_size;
> };
>
> +enum {
> + F2FS_EXTRA_ATTR_TOTAL_SIZE, /* ro, size of extra attr area */
> + F2FS_EXTRA_ATTR_ISIZE, /* ro, i_extra_isize */
> + F2FS_EXTRA_ATTR_INLINE_XATTR_SIZE, /* rw, i_inline_xattr_size */
> + F2FS_EXTRA_ATTR_PROJID, /* ro, i_projid */
> + F2FS_EXTRA_ATTR_INODE_CHKSUM, /* ro, i_inode_chksum */
> + F2FS_EXTRA_ATTR_CRTIME, /* ro, i_crtime, i_crtime_nsec */
> + F2FS_EXTRA_ATTR_COMPR_BLOCKS, /* ro, i_compr_blocks */
> + F2FS_EXTRA_ATTR_COMPR_OPTION, /* rw, i_compress_algorithm,
> + * i_log_cluster_size
> + */
> + F2FS_EXTRA_ATTR_MAX,
> +};
> +
> +struct f2fs_extra_attr {
> + __u8 field; /* F2FS_EXTRA_ATTR_* */
> + __u8 rsvd1;
> + __u16 attr_size; /* size of @attr */
> + __u32 rsvd2;
> + __u64 attr; /* attr value or pointer */
> +};
> #endif /* _UAPI_LINUX_F2FS_H */
> --
> 2.40.1