1 #ifndef FS_CEPH_IOCTL_H 2 #define FS_CEPH_IOCTL_H 3 4 #include <linux/ioctl.h> 5 #include <linux/types.h> 6 7 #define CEPH_IOCTL_MAGIC 0x97 8 9 /* 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 */ 34 struct ceph_ioctl_layout { 35 __u64 stripe_unit, stripe_count, object_size; 36 __u64 data_pool; 37 38 /* obsolete. new values ignored, always return -1 */ 39 __s64 preferred_osd; 40 }; 41 42 #define CEPH_IOC_GET_LAYOUT _IOR(CEPH_IOCTL_MAGIC, 1, \ 43 struct ceph_ioctl_layout) 44 #define CEPH_IOC_SET_LAYOUT _IOW(CEPH_IOCTL_MAGIC, 2, \ 45 struct ceph_ioctl_layout) 46 #define CEPH_IOC_SET_LAYOUT_POLICY _IOW(CEPH_IOCTL_MAGIC, 5, \ 47 struct ceph_ioctl_layout) 48 49 /* 50 * CEPH_IOC_GET_DATALOC - get location of file data in the cluster 51 * 52 * Extract identity, address of the OSD and object storing a given 53 * file offset. 54 */ 55 struct ceph_ioctl_dataloc { 56 __u64 file_offset; /* in+out: file offset */ 57 __u64 object_offset; /* out: offset in object */ 58 __u64 object_no; /* out: object # */ 59 __u64 object_size; /* out: object size */ 60 char object_name[64]; /* out: object name */ 61 __u64 block_offset; /* out: offset in block */ 62 __u64 block_size; /* out: block length */ 63 __s64 osd; /* out: osd # */ 64 struct sockaddr_storage osd_addr; /* out: osd address */ 65 }; 66 67 #define CEPH_IOC_GET_DATALOC _IOWR(CEPH_IOCTL_MAGIC, 3, \ 68 struct ceph_ioctl_dataloc) 69 70 /* 71 * CEPH_IOC_LAZYIO - relax consistency 72 * 73 * Normally Ceph switches to synchronous IO when multiple clients have 74 * the file open (and or more for write). Reads and writes bypass the 75 * page cache and go directly to the OSD. Setting this flag on a file 76 * descriptor will allow buffered IO for this file in cases where the 77 * application knows it won't interfere with other nodes (or doesn't 78 * care). 79 */ 80 #define CEPH_IOC_LAZYIO _IO(CEPH_IOCTL_MAGIC, 4) 81 82 /* 83 * CEPH_IOC_SYNCIO - force synchronous IO 84 * 85 * This ioctl sets a file flag that forces the synchronous IO that 86 * bypasses the page cache, even if it is not necessary. This is 87 * essentially the opposite behavior of IOC_LAZYIO. This forces the 88 * same read/write path as a file opened by multiple clients when one 89 * or more of those clients is opened for write. 90 * 91 * Note that this type of sync IO takes a different path than a file 92 * opened with O_SYNC/D_SYNC (writes hit the page cache and are 93 * immediately flushed on page boundaries). It is very similar to 94 * O_DIRECT (writes bypass the page cache) excep that O_DIRECT writes 95 * are not copied (user page must remain stable) and O_DIRECT writes 96 * have alignment restrictions (on the buffer and file offset). 97 */ 98 #define CEPH_IOC_SYNCIO _IO(CEPH_IOCTL_MAGIC, 5) 99 100 #endif 101