[PATCH v3 1/2] f2fs: add F2FS_IOC_GET_COMPRESS_OPTION ioctl

From: Daeho Jeong
Date: Mon Oct 26 2020 - 00:17:11 EST


From: Daeho Jeong <daehojeong@xxxxxxxxxx>

Added a new F2FS_IOC_GET_COMPRESS_OPTION ioctl to get file compression
option of a file.

struct f2fs_comp_option {
u8 algorithm; => compression algorithm
=> 0:lzo, 1:lz4, 2:zstd, 3:lzorle
u8 log_cluster_size; => log scale cluster size
=> 2 ~ 8
};

struct f2fs_comp_option option;

ioctl(fd, F2FS_IOC_GET_COMPRESS_OPTION, &option);

Signed-off-by: Daeho Jeong <daehojeong@xxxxxxxxxx>
Reviewed-by: Eric Biggers <ebiggers@xxxxxxxxxx>
---

v3: changed the error number more specific.
v2: added ioctl description.
---
fs/f2fs/f2fs.h | 7 +++++++
fs/f2fs/file.c | 30 ++++++++++++++++++++++++++++++
2 files changed, 37 insertions(+)

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 53fe2853579c..a33c90cf979b 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -433,6 +433,8 @@ static inline bool __has_cursum_space(struct f2fs_journal *journal,
_IOR(F2FS_IOCTL_MAGIC, 19, __u64)
#define F2FS_IOC_SEC_TRIM_FILE _IOW(F2FS_IOCTL_MAGIC, 20, \
struct f2fs_sectrim_range)
+#define F2FS_IOC_GET_COMPRESS_OPTION _IOR(F2FS_IOCTL_MAGIC, 21, \
+ struct f2fs_comp_option)

/*
* should be same as XFS_IOC_GOINGDOWN.
@@ -481,6 +483,11 @@ struct f2fs_sectrim_range {
u64 flags;
};

+struct f2fs_comp_option {
+ u8 algorithm;
+ u8 log_cluster_size;
+};
+
/* for inline stuff */
#define DEF_INLINE_RESERVED_SIZE 1
static inline int get_extra_isize(struct inode *inode);
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index ef5a844de53f..8922ab191a9d 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -3936,6 +3936,33 @@ static int f2fs_sec_trim_file(struct file *filp, unsigned long arg)
return ret;
}

+static int f2fs_ioc_get_compress_option(struct file *filp, unsigned long arg)
+{
+ struct inode *inode = file_inode(filp);
+ struct f2fs_comp_option option;
+
+ if (!f2fs_sb_has_compression(F2FS_I_SB(inode)))
+ return -EOPNOTSUPP;
+
+ inode_lock(inode);
+
+ if (!f2fs_compressed_file(inode)) {
+ inode_unlock(inode);
+ return -ENODATA;
+ }
+
+ option.algorithm = F2FS_I(inode)->i_compress_algorithm;
+ option.log_cluster_size = F2FS_I(inode)->i_log_cluster_size;
+
+ inode_unlock(inode);
+
+ if (copy_to_user((struct f2fs_comp_option __user *)arg, &option,
+ sizeof(option)))
+ return -EFAULT;
+
+ return 0;
+}
+
long f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
if (unlikely(f2fs_cp_error(F2FS_I_SB(file_inode(filp)))))
@@ -4024,6 +4051,8 @@ long f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
return f2fs_reserve_compress_blocks(filp, arg);
case F2FS_IOC_SEC_TRIM_FILE:
return f2fs_sec_trim_file(filp, arg);
+ case F2FS_IOC_GET_COMPRESS_OPTION:
+ return f2fs_ioc_get_compress_option(filp, arg);
default:
return -ENOTTY;
}
@@ -4194,6 +4223,7 @@ long f2fs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
case F2FS_IOC_RELEASE_COMPRESS_BLOCKS:
case F2FS_IOC_RESERVE_COMPRESS_BLOCKS:
case F2FS_IOC_SEC_TRIM_FILE:
+ case F2FS_IOC_GET_COMPRESS_OPTION:
break;
default:
return -ENOIOCTLCMD;
--
2.29.0.rc1.297.gfa9743e501-goog