1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2 | #ifndef FS_CEPH_IOCTL_H |
3 | #define FS_CEPH_IOCTL_H |
4 | |
5 | #include <linux/ioctl.h> |
6 | #include <linux/types.h> |
7 | |
8 | #define CEPH_IOCTL_MAGIC 0x97 |
9 | |
10 | /* |
11 | * CEPH_IOC_GET_LAYOUT - get file layout or dir layout policy |
12 | * CEPH_IOC_SET_LAYOUT - set file layout |
13 | * CEPH_IOC_SET_LAYOUT_POLICY - set dir layout policy |
14 | * |
15 | * The file layout specifies how file data is striped over objects in |
16 | * the distributed object store, which object pool they belong to (if |
17 | * it differs from the default), and an optional 'preferred osd' to |
18 | * store them on. |
19 | * |
20 | * Files get a new layout based on the policy set on the containing |
21 | * directory or one of its ancestors. The GET_LAYOUT ioctl will let |
22 | * you examine the layout for a file or the policy on a directory. |
23 | * |
24 | * SET_LAYOUT will let you set a layout on a newly created file. This |
25 | * only works immediately after the file is created and before any |
26 | * data is written to it. |
27 | * |
28 | * SET_LAYOUT_POLICY will let you set a layout policy (default layout) |
29 | * on a directory that will apply to any new files created in that |
30 | * directory (or any child directory that doesn't specify a layout of |
31 | * its own). |
32 | */ |
33 | |
34 | /* use u64 to align sanely on all archs */ |
35 | struct ceph_ioctl_layout { |
36 | __u64 stripe_unit, stripe_count, object_size; |
37 | __u64 data_pool; |
38 | |
39 | /* obsolete. new values ignored, always return -1 */ |
40 | __s64 preferred_osd; |
41 | }; |
42 | |
43 | #define CEPH_IOC_GET_LAYOUT _IOR(CEPH_IOCTL_MAGIC, 1, \ |
44 | struct ceph_ioctl_layout) |
45 | #define CEPH_IOC_SET_LAYOUT _IOW(CEPH_IOCTL_MAGIC, 2, \ |
46 | struct ceph_ioctl_layout) |
47 | #define CEPH_IOC_SET_LAYOUT_POLICY _IOW(CEPH_IOCTL_MAGIC, 5, \ |
48 | struct ceph_ioctl_layout) |
49 | |
50 | /* |
51 | * CEPH_IOC_GET_DATALOC - get location of file data in the cluster |
52 | * |
53 | * Extract identity, address of the OSD and object storing a given |
54 | * file offset. |
55 | */ |
56 | struct ceph_ioctl_dataloc { |
57 | __u64 file_offset; /* in+out: file offset */ |
58 | __u64 object_offset; /* out: offset in object */ |
59 | __u64 object_no; /* out: object # */ |
60 | __u64 object_size; /* out: object size */ |
61 | char object_name[64]; /* out: object name */ |
62 | __u64 block_offset; /* out: offset in block */ |
63 | __u64 block_size; /* out: block length */ |
64 | __s64 osd; /* out: osd # */ |
65 | struct sockaddr_storage osd_addr; /* out: osd address */ |
66 | }; |
67 | |
68 | #define CEPH_IOC_GET_DATALOC _IOWR(CEPH_IOCTL_MAGIC, 3, \ |
69 | struct ceph_ioctl_dataloc) |
70 | |
71 | /* |
72 | * CEPH_IOC_LAZYIO - relax consistency |
73 | * |
74 | * Normally Ceph switches to synchronous IO when multiple clients have |
75 | * the file open (and or more for write). Reads and writes bypass the |
76 | * page cache and go directly to the OSD. Setting this flag on a file |
77 | * descriptor will allow buffered IO for this file in cases where the |
78 | * application knows it won't interfere with other nodes (or doesn't |
79 | * care). |
80 | */ |
81 | #define CEPH_IOC_LAZYIO _IO(CEPH_IOCTL_MAGIC, 4) |
82 | |
83 | /* |
84 | * CEPH_IOC_SYNCIO - force synchronous IO |
85 | * |
86 | * This ioctl sets a file flag that forces the synchronous IO that |
87 | * bypasses the page cache, even if it is not necessary. This is |
88 | * essentially the opposite behavior of IOC_LAZYIO. This forces the |
89 | * same read/write path as a file opened by multiple clients when one |
90 | * or more of those clients is opened for write. |
91 | * |
92 | * Note that this type of sync IO takes a different path than a file |
93 | * opened with O_SYNC/D_SYNC (writes hit the page cache and are |
94 | * immediately flushed on page boundaries). It is very similar to |
95 | * O_DIRECT (writes bypass the page cache) excep that O_DIRECT writes |
96 | * are not copied (user page must remain stable) and O_DIRECT writes |
97 | * have alignment restrictions (on the buffer and file offset). |
98 | */ |
99 | #define CEPH_IOC_SYNCIO _IO(CEPH_IOCTL_MAGIC, 5) |
100 | |
101 | #endif |
102 | |