[PATCH 2/3] f2fs: add F2FS_IOC_SET_COMPRESS_OPTION_V2 ioctl

[Yangtao Li]

Added a new F2FS_IOC_SET_COMPRESS_OPTION_V2 ioctl to change 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;

option.algorithm = 2;
option.log_cluster_size = 2;
option.compress_flag = (5 << COMPRESS_LEVEL_OFFSET) | BIT(COMPRESS_CHKSUM);

ioctl(fd, F2FS_IOC_SET_COMPRESS_OPTION_V2, &option);

Signed-off-by: Yangtao Li <frank.li@xxxxxxxx>
---
 fs/f2fs/f2fs.h            |  8 +-------
 fs/f2fs/file.c            | 41 ++++++++++++++++++++++++++++++++-------
 include/uapi/linux/f2fs.h | 21 ++++++++++++++++++++
 3 files changed, 56 insertions(+), 14 deletions(-)

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index f3c5f7740c1a..c2267f44bcf8 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -25,6 +25,7 @@
 #include <linux/quotaops.h>
 #include <linux/part_stat.h>
 #include <crypto/hash.h>
+#include <uapi/linux/f2fs.h>
 
 #include <linux/fscrypt.h>
 #include <linux/fsverity.h>
@@ -1501,11 +1502,6 @@ enum compress_algorithm_type {
 	COMPRESS_MAX,
 };
 
-enum compress_flag {
-	COMPRESS_CHKSUM,
-	COMPRESS_MAX_FLAG,
-};
-
 #define	COMPRESS_WATERMARK			20
 #define	COMPRESS_PERCENT			20
 
@@ -1521,8 +1517,6 @@ struct compress_data {
 
 #define F2FS_COMPRESSED_PAGE_MAGIC	0xF5F2C000
 
-#define	COMPRESS_LEVEL_OFFSET	8
-
 /* compress context */
 struct compress_ctx {
 	struct inode *inode;		/* inode the context belong to */
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index f5c1b7814954..719706ef0d46 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -25,6 +25,8 @@
 #include <linux/fileattr.h>
 #include <linux/fadvise.h>
 #include <linux/iomap.h>
+#include <linux/zstd.h>
+#include <linux/lz4.h>
 
 #include "f2fs.h"
 #include "node.h"
@@ -3910,12 +3912,13 @@ static int f2fs_ioc_get_compress_option(struct file *filp, unsigned long arg)
 	return 0;
 }
 
-static int f2fs_ioc_set_compress_option(struct file *filp, unsigned long arg)
+static int f2fs_ioc_set_compress_option(struct file *filp, unsigned long arg,
+										unsigned int cmd)
 {
 	struct inode *inode = file_inode(filp);
 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
-	struct f2fs_comp_option option;
-	int ret = 0;
+	struct f2fs_comp_option_v2 option;
+	int ret = 0, len;
 
 	if (!f2fs_sb_has_compression(sbi))
 		return -EOPNOTSUPP;
@@ -3923,8 +3926,12 @@ static int f2fs_ioc_set_compress_option(struct file *filp, unsigned long arg)
 	if (!(filp->f_mode & FMODE_WRITE))
 		return -EBADF;
 
-	if (copy_from_user(&option, (struct f2fs_comp_option __user *)arg,
-				sizeof(option)))
+	if (cmd == F2FS_IOC_SET_COMPRESS_OPTION_V2)
+		len = sizeof(struct f2fs_comp_option_v2);
+	else
+		len = sizeof(struct f2fs_comp_option);
+
+	if (copy_from_user(&option, (void __user *)arg, len))
 		return -EFAULT;
 
 	if (!f2fs_compressed_file(inode) ||
@@ -3933,6 +3940,21 @@ static int f2fs_ioc_set_compress_option(struct file *filp, unsigned long arg)
 			option.algorithm >= COMPRESS_MAX)
 		return -EINVAL;
 
+	if (cmd == F2FS_IOC_SET_COMPRESS_OPTION_V2) {
+		unsigned int level = GET_COMPRESS_LEVEL(option.compress_flag);
+
+		switch (option.algorithm) {
+		case COMPRESS_LZ4:
+			if (level < LZ4HC_MIN_CLEVEL || level > LZ4HC_MAX_CLEVEL)
+				return -EINVAL;
+			break;
+		case COMPRESS_ZSTD:
+			if (!level || level > zstd_max_clevel())
+				return -EINVAL;
+			break;
+		}
+	}
+
 	file_start_write(filp);
 	inode_lock(inode);
 
@@ -3948,7 +3970,10 @@ static int f2fs_ioc_set_compress_option(struct file *filp, unsigned long arg)
 
 	F2FS_I(inode)->i_compress_algorithm = option.algorithm;
 	F2FS_I(inode)->i_log_cluster_size = option.log_cluster_size;
-	F2FS_I(inode)->i_cluster_size = 1 << option.log_cluster_size;
+	F2FS_I(inode)->i_cluster_size = BIT(option.log_cluster_size);
+
+	if (cmd == F2FS_IOC_SET_COMPRESS_OPTION_V2)
+		F2FS_I(inode)->i_compress_flag = option.compress_flag & COMPRESS_OPTION_MASK;
 	f2fs_mark_inode_dirty_sync(inode, true);
 
 	if (!f2fs_is_compress_backend_ready(inode))
@@ -4221,7 +4246,9 @@ static long __f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 	case F2FS_IOC_GET_COMPRESS_OPTION:
 		return f2fs_ioc_get_compress_option(filp, arg);
 	case F2FS_IOC_SET_COMPRESS_OPTION:
-		return f2fs_ioc_set_compress_option(filp, arg);
+		return f2fs_ioc_set_compress_option(filp, arg, F2FS_IOC_SET_COMPRESS_OPTION);
+	case F2FS_IOC_SET_COMPRESS_OPTION_V2:
+		return f2fs_ioc_set_compress_option(filp, arg, F2FS_IOC_SET_COMPRESS_OPTION_V2);
 	case F2FS_IOC_DECOMPRESS_FILE:
 		return f2fs_ioc_decompress_file(filp, arg);
 	case F2FS_IOC_COMPRESS_FILE:
diff --git a/include/uapi/linux/f2fs.h b/include/uapi/linux/f2fs.h
index 955d440be104..aaf7f55273fb 100644
--- a/include/uapi/linux/f2fs.h
+++ b/include/uapi/linux/f2fs.h
@@ -43,6 +43,8 @@
 #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_SET_COMPRESS_OPTION_V2	_IOW(F2FS_IOCTL_MAGIC, 26,	\
+						struct f2fs_comp_option_v2)
 
 /*
  * should be same as XFS_IOC_GOINGDOWN.
@@ -62,6 +64,15 @@
 #define F2FS_TRIM_FILE_ZEROOUT		0x2	/* zero out */
 #define F2FS_TRIM_FILE_MASK		0x3
 
+/*
+ * Flags used by F2FS_IOC_SET_COMPRESS_OPTION_V2
+ */
+#define COMPRESS_CHKSUM				0x0 /* enable chksum for compress file */
+#define COMPRESS_LEVEL_OFFSET	8
+#define COMPRESS_LEVEL_MASK		GENMASK(15, COMPRESS_LEVEL_OFFSET)
+#define COMPRESS_OPTION_MASK	(COMPRESS_LEVEL_MASK | BIT(COMPRESS_CHKSUM))
+#define GET_COMPRESS_LEVEL(x)	(((x) & COMPRESS_LEVEL_MASK) >> COMPRESS_LEVEL_OFFSET)
+
 struct f2fs_gc_range {
 	__u32 sync;
 	__u64 start;
@@ -96,4 +107,14 @@ struct f2fs_comp_option {
 	__u8 log_cluster_size;
 };
 
+struct f2fs_comp_option_v2 {
+	union {
+		struct {
+			__u8 algorithm;
+			__u8 log_cluster_size;
+			__u16 compress_flag;
+		};
+		struct f2fs_comp_option option;
+	};
+};
 #endif /* _UAPI_LINUX_F2FS_H */
-- 
2.25.1