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linux/fs/ocfs2/ocfs2_ioctl.h
Tristan Ye ddee5cdb70 Ocfs2: Add new OCFS2_IOC_INFO ioctl for ocfs2 v8.
The reason why we need this ioctl is to offer the none-privileged
end-user a possibility to get filesys info gathering.

We use OCFS2_IOC_INFO to manipulate the new ioctl, userspace passes a
structure to kernel containing an array of request pointers and request
count, such as,

* From userspace:

struct ocfs2_info_blocksize oib = {
        .ib_req = {
                .ir_magic = OCFS2_INFO_MAGIC,
                .ir_code = OCFS2_INFO_BLOCKSIZE,
                ...
        }
        ...
}

struct ocfs2_info_clustersize oic = {
        ...
}

uint64_t reqs[2] = {(unsigned long)&oib,
                    (unsigned long)&oic};

struct ocfs2_info info = {
        .oi_requests = reqs,
        .oi_count = 2,
}

ret = ioctl(fd, OCFS2_IOC_INFO, &info);

* In kernel:

Get the request pointers from *info*, then handle each request one bye one.

Idea here is to make the spearated request small enough to guarantee
a better backward&forward compatibility since a small piece of request
would be less likely to be broken if filesys on raw disk get changed.

Currently, the following 7 requests are supported per the requirement from
userspace tool o2info, and I believe it will grow over time:-)

        OCFS2_INFO_CLUSTERSIZE
        OCFS2_INFO_BLOCKSIZE
        OCFS2_INFO_MAXSLOTS
        OCFS2_INFO_LABEL
        OCFS2_INFO_UUID
        OCFS2_INFO_FS_FEATURES
        OCFS2_INFO_JOURNAL_SIZE

This ioctl is only specific to OCFS2.

Signed-off-by: Tristan Ye <tristan.ye@oracle.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
2010-09-10 08:35:41 -07:00

175 lines
4.9 KiB
C

/* -*- mode: c; c-basic-offset: 8; -*-
* vim: noexpandtab sw=8 ts=8 sts=0:
*
* ocfs2_ioctl.h
*
* Defines OCFS2 ioctls.
*
* Copyright (C) 2010 Oracle. All rights reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License, version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*/
#ifndef OCFS2_IOCTL_H
#define OCFS2_IOCTL_H
/*
* ioctl commands
*/
#define OCFS2_IOC_GETFLAGS _IOR('f', 1, long)
#define OCFS2_IOC_SETFLAGS _IOW('f', 2, long)
#define OCFS2_IOC32_GETFLAGS _IOR('f', 1, int)
#define OCFS2_IOC32_SETFLAGS _IOW('f', 2, int)
/*
* Space reservation / allocation / free ioctls and argument structure
* are designed to be compatible with XFS.
*
* ALLOCSP* and FREESP* are not and will never be supported, but are
* included here for completeness.
*/
struct ocfs2_space_resv {
__s16 l_type;
__s16 l_whence;
__s64 l_start;
__s64 l_len; /* len == 0 means until end of file */
__s32 l_sysid;
__u32 l_pid;
__s32 l_pad[4]; /* reserve area */
};
#define OCFS2_IOC_ALLOCSP _IOW ('X', 10, struct ocfs2_space_resv)
#define OCFS2_IOC_FREESP _IOW ('X', 11, struct ocfs2_space_resv)
#define OCFS2_IOC_RESVSP _IOW ('X', 40, struct ocfs2_space_resv)
#define OCFS2_IOC_UNRESVSP _IOW ('X', 41, struct ocfs2_space_resv)
#define OCFS2_IOC_ALLOCSP64 _IOW ('X', 36, struct ocfs2_space_resv)
#define OCFS2_IOC_FREESP64 _IOW ('X', 37, struct ocfs2_space_resv)
#define OCFS2_IOC_RESVSP64 _IOW ('X', 42, struct ocfs2_space_resv)
#define OCFS2_IOC_UNRESVSP64 _IOW ('X', 43, struct ocfs2_space_resv)
/* Used to pass group descriptor data when online resize is done */
struct ocfs2_new_group_input {
__u64 group; /* Group descriptor's blkno. */
__u32 clusters; /* Total number of clusters in this group */
__u32 frees; /* Total free clusters in this group */
__u16 chain; /* Chain for this group */
__u16 reserved1;
__u32 reserved2;
};
#define OCFS2_IOC_GROUP_EXTEND _IOW('o', 1, int)
#define OCFS2_IOC_GROUP_ADD _IOW('o', 2,struct ocfs2_new_group_input)
#define OCFS2_IOC_GROUP_ADD64 _IOW('o', 3,struct ocfs2_new_group_input)
/* Used to pass 2 file names to reflink. */
struct reflink_arguments {
__u64 old_path;
__u64 new_path;
__u64 preserve;
};
#define OCFS2_IOC_REFLINK _IOW('o', 4, struct reflink_arguments)
/* Following definitions dedicated for ocfs2_info_request ioctls. */
#define OCFS2_INFO_MAX_REQUEST (50)
#define OCFS2_TEXT_UUID_LEN (OCFS2_VOL_UUID_LEN * 2)
/* Magic number of all requests */
#define OCFS2_INFO_MAGIC (0x4F32494E)
/*
* Always try to separate info request into small pieces to
* guarantee the backward&forward compatibility.
*/
struct ocfs2_info {
__u64 oi_requests; /* Array of __u64 pointers to requests */
__u32 oi_count; /* Number of requests in info_requests */
__u32 oi_pad;
};
struct ocfs2_info_request {
/*00*/ __u32 ir_magic; /* Magic number */
__u32 ir_code; /* Info request code */
__u32 ir_size; /* Size of request */
__u32 ir_flags; /* Request flags */
/*10*/ /* Request specific fields */
};
struct ocfs2_info_clustersize {
struct ocfs2_info_request ic_req;
__u32 ic_clustersize;
__u32 ic_pad;
};
struct ocfs2_info_blocksize {
struct ocfs2_info_request ib_req;
__u32 ib_blocksize;
__u32 ib_pad;
};
struct ocfs2_info_maxslots {
struct ocfs2_info_request im_req;
__u32 im_max_slots;
__u32 im_pad;
};
struct ocfs2_info_label {
struct ocfs2_info_request il_req;
__u8 il_label[OCFS2_MAX_VOL_LABEL_LEN];
} __attribute__ ((packed));
struct ocfs2_info_uuid {
struct ocfs2_info_request iu_req;
__u8 iu_uuid_str[OCFS2_TEXT_UUID_LEN + 1];
} __attribute__ ((packed));
struct ocfs2_info_fs_features {
struct ocfs2_info_request if_req;
__u32 if_compat_features;
__u32 if_incompat_features;
__u32 if_ro_compat_features;
__u32 if_pad;
};
struct ocfs2_info_journal_size {
struct ocfs2_info_request ij_req;
__u64 ij_journal_size;
};
/* Codes for ocfs2_info_request */
enum ocfs2_info_type {
OCFS2_INFO_CLUSTERSIZE = 1,
OCFS2_INFO_BLOCKSIZE,
OCFS2_INFO_MAXSLOTS,
OCFS2_INFO_LABEL,
OCFS2_INFO_UUID,
OCFS2_INFO_FS_FEATURES,
OCFS2_INFO_JOURNAL_SIZE,
OCFS2_INFO_NUM_TYPES
};
/* Flags for struct ocfs2_info_request */
/* Filled by the caller */
#define OCFS2_INFO_FL_NON_COHERENT (0x00000001) /* Cluster coherency not
required. This is a hint.
It is up to ocfs2 whether
the request can be fulfilled
without locking. */
/* Filled by ocfs2 */
#define OCFS2_INFO_FL_FILLED (0x40000000) /* Filesystem understood
this request and
filled in the answer */
#define OCFS2_INFO_FL_ERROR (0x80000000) /* Error happened during
request handling. */
#define OCFS2_IOC_INFO _IOR('o', 5, struct ocfs2_info)
#endif /* OCFS2_IOCTL_H */