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1/* SPDX-License-Identifier: GPL-2.0 */2#ifndef FS_CEPH_IOCTL_H3#define FS_CEPH_IOCTL_H4 5#include <linux/ioctl.h>6#include <linux/types.h>7 8#define CEPH_IOCTL_MAGIC 0x979 10/*11 * CEPH_IOC_GET_LAYOUT - get file layout or dir layout policy12 * CEPH_IOC_SET_LAYOUT - set file layout13 * CEPH_IOC_SET_LAYOUT_POLICY - set dir layout policy14 *15 * The file layout specifies how file data is striped over objects in16 * the distributed object store, which object pool they belong to (if17 * it differs from the default), and an optional 'preferred osd' to18 * store them on.19 *20 * Files get a new layout based on the policy set on the containing21 * directory or one of its ancestors. The GET_LAYOUT ioctl will let22 * 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. This25 * only works immediately after the file is created and before any26 * 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 that30 * directory (or any child directory that doesn't specify a layout of31 * its own).32 */33 34/* use u64 to align sanely on all archs */35struct 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 cluster52 *53 * Extract identity, address of the OSD and object storing a given54 * file offset.55 */56struct 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 consistency73 *74 * Normally Ceph switches to synchronous IO when multiple clients have75 * the file open (and or more for write). Reads and writes bypass the76 * page cache and go directly to the OSD. Setting this flag on a file77 * descriptor will allow buffered IO for this file in cases where the78 * application knows it won't interfere with other nodes (or doesn't79 * care).80 */81#define CEPH_IOC_LAZYIO _IO(CEPH_IOCTL_MAGIC, 4)82 83/*84 * CEPH_IOC_SYNCIO - force synchronous IO85 *86 * This ioctl sets a file flag that forces the synchronous IO that87 * bypasses the page cache, even if it is not necessary. This is88 * essentially the opposite behavior of IOC_LAZYIO. This forces the89 * same read/write path as a file opened by multiple clients when one90 * or more of those clients is opened for write.91 *92 * Note that this type of sync IO takes a different path than a file93 * opened with O_SYNC/D_SYNC (writes hit the page cache and are94 * immediately flushed on page boundaries). It is very similar to95 * O_DIRECT (writes bypass the page cache) excep that O_DIRECT writes96 * are not copied (user page must remain stable) and O_DIRECT writes97 * have alignment restrictions (on the buffer and file offset).98 */99#define CEPH_IOC_SYNCIO _IO(CEPH_IOCTL_MAGIC, 5)100 101#endif102