From: Daeho Jeong <daehojeong@google.com>
Date: Fri, 30 Oct 2020 04:10:34 +0000 (+0900)
Subject: f2fs: add F2FS_IOC_GET_COMPRESS_OPTION ioctl
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=9e2a5f8cfb4d9371783e21e27bba4338401f1260;p=linux.git

f2fs: add F2FS_IOC_GET_COMPRESS_OPTION ioctl

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@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
---

diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 89c451f09344a..c747f5dd595ca 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -3945,6 +3945,33 @@ err:
 	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_shared(inode);
+
+	if (!f2fs_compressed_file(inode)) {
+		inode_unlock_shared(inode);
+		return -ENODATA;
+	}
+
+	option.algorithm = F2FS_I(inode)->i_compress_algorithm;
+	option.log_cluster_size = F2FS_I(inode)->i_log_cluster_size;
+
+	inode_unlock_shared(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)))))
@@ -4033,6 +4060,8 @@ 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;
 	}
@@ -4203,6 +4232,7 @@ 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;
diff --git a/include/uapi/linux/f2fs.h b/include/uapi/linux/f2fs.h
index 28bcfe8d2c27e..872e61d78f29f 100644
--- a/include/uapi/linux/f2fs.h
+++ b/include/uapi/linux/f2fs.h
@@ -36,6 +36,8 @@
 					_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.
@@ -84,4 +86,9 @@ struct f2fs_sectrim_range {
 	__u64 flags;
 };
 
+struct f2fs_comp_option {
+	__u8 algorithm;
+	__u8 log_cluster_size;
+};
+
 #endif /* _UAPI_LINUX_F2FS_H */