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Sage Weil8f4e91d2009-10-06 11:31:14 -07001#ifndef FS_CEPH_IOCTL_H
2#define FS_CEPH_IOCTL_H
3
4#include <linux/ioctl.h>
5#include <linux/types.h>
6
Sage Weil1cd275f2010-12-06 09:45:22 -08007#define CEPH_IOCTL_MAGIC 0x97
Sage Weil8f4e91d2009-10-06 11:31:14 -07008
Sage Weil6a8ea472011-08-04 15:41:37 -07009/*
10 * CEPH_IOC_GET_LAYOUT - get file layout or dir layout policy
11 * CEPH_IOC_SET_LAYOUT - set file layout
12 * CEPH_IOC_SET_LAYOUT_POLICY - set dir layout policy
13 *
14 * The file layout specifies how file data is striped over objects in
15 * the distributed object store, which object pool they belong to (if
16 * it differs from the default), and an optional 'preferred osd' to
17 * store them on.
18 *
19 * Files get a new layout based on the policy set on the containing
20 * directory or one of its ancestors. The GET_LAYOUT ioctl will let
21 * you examine the layout for a file or the policy on a directory.
22 *
23 * SET_LAYOUT will let you set a layout on a newly created file. This
24 * only works immediately after the file is created and before any
25 * data is written to it.
26 *
27 * SET_LAYOUT_POLICY will let you set a layout policy (default layout)
28 * on a directory that will apply to any new files created in that
29 * directory (or any child directory that doesn't specify a layout of
30 * its own).
31 */
32
33/* use u64 to align sanely on all archs */
Sage Weil8f4e91d2009-10-06 11:31:14 -070034struct ceph_ioctl_layout {
35 __u64 stripe_unit, stripe_count, object_size;
36 __u64 data_pool;
Sage Weil33d49092009-12-02 14:42:39 -080037 __s64 preferred_osd;
Sage Weil8f4e91d2009-10-06 11:31:14 -070038};
39
40#define CEPH_IOC_GET_LAYOUT _IOR(CEPH_IOCTL_MAGIC, 1, \
41 struct ceph_ioctl_layout)
42#define CEPH_IOC_SET_LAYOUT _IOW(CEPH_IOCTL_MAGIC, 2, \
43 struct ceph_ioctl_layout)
Greg Farnum571dba52010-09-24 14:56:40 -070044#define CEPH_IOC_SET_LAYOUT_POLICY _IOW(CEPH_IOCTL_MAGIC, 5, \
45 struct ceph_ioctl_layout)
Sage Weil8f4e91d2009-10-06 11:31:14 -070046
47/*
Sage Weil6a8ea472011-08-04 15:41:37 -070048 * CEPH_IOC_GET_DATALOC - get location of file data in the cluster
49 *
Sage Weil8f4e91d2009-10-06 11:31:14 -070050 * Extract identity, address of the OSD and object storing a given
51 * file offset.
52 */
53struct ceph_ioctl_dataloc {
54 __u64 file_offset; /* in+out: file offset */
55 __u64 object_offset; /* out: offset in object */
56 __u64 object_no; /* out: object # */
57 __u64 object_size; /* out: object size */
58 char object_name[64]; /* out: object name */
59 __u64 block_offset; /* out: offset in block */
60 __u64 block_size; /* out: block length */
61 __s64 osd; /* out: osd # */
62 struct sockaddr_storage osd_addr; /* out: osd address */
63};
64
65#define CEPH_IOC_GET_DATALOC _IOWR(CEPH_IOCTL_MAGIC, 3, \
66 struct ceph_ioctl_dataloc)
67
Sage Weil6a8ea472011-08-04 15:41:37 -070068/*
69 * CEPH_IOC_LAZYIO - relax consistency
70 *
71 * Normally Ceph switches to synchronous IO when multiple clients have
72 * the file open (and or more for write). Reads and writes bypass the
73 * page cache and go directly to the OSD. Setting this flag on a file
74 * descriptor will allow buffered IO for this file in cases where the
75 * application knows it won't interfere with other nodes (or doesn't
76 * care).
77 */
Sage Weil8c6e9222010-04-16 09:53:43 -070078#define CEPH_IOC_LAZYIO _IO(CEPH_IOCTL_MAGIC, 4)
Sage Weil6a8ea472011-08-04 15:41:37 -070079
80/*
81 * CEPH_IOC_SYNCIO - force synchronous IO
82 *
83 * This ioctl sets a file flag that forces the synchronous IO that
84 * bypasses the page cache, even if it is not necessary. This is
85 * essentially the opposite behavior of IOC_LAZYIO. This forces the
86 * same read/write path as a file opened by multiple clients when one
87 * or more of those clients is opened for write.
88 *
89 * Note that this type of sync IO takes a different path than a file
90 * opened with O_SYNC/D_SYNC (writes hit the page cache and are
91 * immediately flushed on page boundaries). It is very similar to
92 * O_DIRECT (writes bypass the page cache) excep that O_DIRECT writes
93 * are not copied (user page must remain stable) and O_DIRECT writes
94 * have alignment restrictions (on the buffer and file offset).
95 */
Sage Weil4918b6d2011-07-26 11:26:07 -070096#define CEPH_IOC_SYNCIO _IO(CEPH_IOCTL_MAGIC, 5)
Sage Weil8c6e9222010-04-16 09:53:43 -070097
Sage Weil8f4e91d2009-10-06 11:31:14 -070098#endif