[PATCH v2 2/2] f2fs: add F2FS_IOC_GET_COMPRESS_OPTION_V2 ioctl

[Yangtao Li]

Added a new F2FS_IOC_GET_COMPRESS_OPTION_V2 ioctl to get file compression
option of a file.

struct f2fs_comp_option_v2 {
	union {
		struct {
			__u8 algorithm;
			__u8 log_cluster_size;
			__u16 compress_flag;
		};
		struct f2fs_comp_option option;
	};
};

struct f2fs_comp_option_v2 option;

ioctl(fd, F2FS_IOC_GET_COMPRESS_OPTION_V2, &option);

printf("compression algorithm:%u\n", option.algorithm);
printf("compression cluster log size:%u\n", option.log_cluster_size);
printf("compress level:%u\n", GET_COMPRESS_LEVEL(option.compress_flag));
printf("compress chksum:%s\n",
		(BIT(COMPRESS_CHKSUM) & option.compress_flag) ? "true" : "false");

Signed-off-by: Yangtao Li <frank.li@xxxxxxxx>
---
v2:
-handle F2FS_IOC_GET_COMPRESS_OPTION_V2 in f2fs_compat_ioctl
 fs/f2fs/file.c            | 21 ++++++++++++++++-----
 include/uapi/linux/f2fs.h |  4 +++-
 2 files changed, 19 insertions(+), 6 deletions(-)

diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 78b97c1fa6af..b3bcb50490bd 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -3899,10 +3899,12 @@ 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)
+static int f2fs_ioc_get_compress_option(struct file *filp, unsigned long arg,
+						unsigned int cmd)
 {
 	struct inode *inode = file_inode(filp);
-	struct f2fs_comp_option option;
+	struct f2fs_comp_option_v2 option;
+	int len;
 
 	if (!f2fs_sb_has_compression(F2FS_I_SB(inode)))
 		return -EOPNOTSUPP;
@@ -3916,11 +3918,17 @@ static int f2fs_ioc_get_compress_option(struct file *filp, unsigned long arg)
 
 	option.algorithm = F2FS_I(inode)->i_compress_algorithm;
 	option.log_cluster_size = F2FS_I(inode)->i_log_cluster_size;
+	if (cmd == F2FS_IOC_GET_COMPRESS_OPTION_V2)
+		option.compress_flag = F2FS_I(inode)->i_compress_flag;
 
 	inode_unlock_shared(inode);
 
-	if (copy_to_user((struct f2fs_comp_option __user *)arg, &option,
-				sizeof(option)))
+	if (cmd == F2FS_IOC_GET_COMPRESS_OPTION_V2)
+		len = sizeof(struct f2fs_comp_option_v2);
+	else
+		len = sizeof(struct f2fs_comp_option);
+
+	if (copy_to_user((void __user *)arg, &option, len))
 		return -EFAULT;
 
 	return 0;
@@ -4263,7 +4271,9 @@ static long __f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long 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);
+		return f2fs_ioc_get_compress_option(filp, arg, F2FS_IOC_GET_COMPRESS_OPTION);
+	case F2FS_IOC_GET_COMPRESS_OPTION_V2:
+		return f2fs_ioc_get_compress_option(filp, arg, F2FS_IOC_GET_COMPRESS_OPTION_V2);
 	case F2FS_IOC_SET_COMPRESS_OPTION:
 		return f2fs_ioc_set_compress_option(filp, arg, F2FS_IOC_SET_COMPRESS_OPTION);
 	case F2FS_IOC_SET_COMPRESS_OPTION_V2:
@@ -4902,6 +4912,7 @@ long f2fs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 	case F2FS_IOC_RESERVE_COMPRESS_BLOCKS:
 	case F2FS_IOC_SEC_TRIM_FILE:
 	case F2FS_IOC_GET_COMPRESS_OPTION:
+	case F2FS_IOC_GET_COMPRESS_OPTION_V2:
 	case F2FS_IOC_SET_COMPRESS_OPTION:
 	case F2FS_IOC_SET_COMPRESS_OPTION_V2:
 	case F2FS_IOC_DECOMPRESS_FILE:
diff --git a/include/uapi/linux/f2fs.h b/include/uapi/linux/f2fs.h
index 640569444200..b82dc386e59e 100644
--- a/include/uapi/linux/f2fs.h
+++ b/include/uapi/linux/f2fs.h
@@ -45,6 +45,8 @@
 #define F2FS_IOC_START_ATOMIC_REPLACE	_IO(F2FS_IOCTL_MAGIC, 25)
 #define F2FS_IOC_SET_COMPRESS_OPTION_V2	_IOW(F2FS_IOCTL_MAGIC, 26,	\
 						struct f2fs_comp_option_v2)
+#define F2FS_IOC_GET_COMPRESS_OPTION_V2	_IOW(F2FS_IOCTL_MAGIC, 27,	\
+						struct f2fs_comp_option_v2)
 
 /*
  * should be same as XFS_IOC_GOINGDOWN.
@@ -65,7 +67,7 @@
 #define F2FS_TRIM_FILE_MASK		0x3
 
 /*
- * Flags used by F2FS_IOC_SET_COMPRESS_OPTION_V2
+ * Flags used by F2FS_IOC_SET_COMPRESS_OPTION_V2 and F2FS_IOC_GET_COMPRESS_OPTION
  */
 #define COMPRESS_CHKSUM		0x0 /* enable chksum for compress file */
 #define COMPRESS_LEVEL_OFFSET		8
-- 
2.25.1