LXR linux/include/linux/ceph/libceph.h

   1#ifndef _FS_CEPH_LIBCEPH_H
   2#define _FS_CEPH_LIBCEPH_H
   3
   4#include <linux/ceph/ceph_debug.h>
   5
   6#include <asm/unaligned.h>
   7#include <linux/backing-dev.h>
   8#include <linux/completion.h>
   9#include <linux/exportfs.h>
  10#include <linux/bug.h>
  11#include <linux/fs.h>
  12#include <linux/mempool.h>
  13#include <linux/pagemap.h>
  14#include <linux/wait.h>
  15#include <linux/writeback.h>
  16#include <linux/slab.h>
  17
  18#include <linux/ceph/types.h>
  19#include <linux/ceph/messenger.h>
  20#include <linux/ceph/msgpool.h>
  21#include <linux/ceph/mon_client.h>
  22#include <linux/ceph/osd_client.h>
  23#include <linux/ceph/ceph_fs.h>
  24
  25/*
  26 * mount options
  27 */
  28#define CEPH_OPT_FSID             (1<<0)
  29#define CEPH_OPT_NOSHARE          (1<<1) /* don't share client with other sbs */
  30#define CEPH_OPT_MYIP             (1<<2) /* specified my ip */
  31#define CEPH_OPT_NOCRC            (1<<3) /* no data crc on writes */
  32
  33#define CEPH_OPT_DEFAULT   (0)
  34
  35#define ceph_set_opt(client, opt) \
  36        (client)->options->flags |= CEPH_OPT_##opt;
  37#define ceph_test_opt(client, opt) \
  38        (!!((client)->options->flags & CEPH_OPT_##opt))
  39
  40struct ceph_options {
  41        int flags;
  42        struct ceph_fsid fsid;
  43        struct ceph_entity_addr my_addr;
  44        int mount_timeout;
  45        int osd_idle_ttl;
  46        int osd_keepalive_timeout;
  47
  48        /*
  49         * any type that can't be simply compared or doesn't need need
  50         * to be compared should go beyond this point,
  51         * ceph_compare_options() should be updated accordingly
  52         */
  53
  54        struct ceph_entity_addr *mon_addr; /* should be the first
  55                                              pointer type of args */
  56        int num_mon;
  57        char *name;
  58        struct ceph_crypto_key *key;
  59};
  60
  61/*
  62 * defaults
  63 */
  64#define CEPH_MOUNT_TIMEOUT_DEFAULT  60
  65#define CEPH_OSD_KEEPALIVE_DEFAULT  5
  66#define CEPH_OSD_IDLE_TTL_DEFAULT    60
  67
  68#define CEPH_MSG_MAX_FRONT_LEN  (16*1024*1024)
  69#define CEPH_MSG_MAX_MIDDLE_LEN (16*1024*1024)
  70#define CEPH_MSG_MAX_DATA_LEN   (16*1024*1024)
  71
  72#define CEPH_AUTH_NAME_DEFAULT   "guest"
  73
  74/*
  75 * Delay telling the MDS we no longer want caps, in case we reopen
  76 * the file.  Delay a minimum amount of time, even if we send a cap
  77 * message for some other reason.  Otherwise, take the oppotunity to
  78 * update the mds to avoid sending another message later.
  79 */
  80#define CEPH_CAPS_WANTED_DELAY_MIN_DEFAULT      5  /* cap release delay */
  81#define CEPH_CAPS_WANTED_DELAY_MAX_DEFAULT     60  /* cap release delay */
  82
  83#define CEPH_CAP_RELEASE_SAFETY_DEFAULT        (CEPH_CAPS_PER_RELEASE * 4)
  84
  85/* mount state */
  86enum {
  87        CEPH_MOUNT_MOUNTING,
  88        CEPH_MOUNT_MOUNTED,
  89        CEPH_MOUNT_UNMOUNTING,
  90        CEPH_MOUNT_UNMOUNTED,
  91        CEPH_MOUNT_SHUTDOWN,
  92};
  93
  94/*
  95 * subtract jiffies
  96 */
  97static inline unsigned long time_sub(unsigned long a, unsigned long b)
  98{
  99        BUG_ON(time_after(b, a));
 100        return (long)a - (long)b;
 101}
 102
 103struct ceph_mds_client;
 104
 105/*
 106 * per client state
 107 *
 108 * possibly shared by multiple mount points, if they are
 109 * mounting the same ceph filesystem/cluster.
 110 */
 111struct ceph_client {
 112        struct ceph_fsid fsid;
 113        bool have_fsid;
 114
 115        void *private;
 116
 117        struct ceph_options *options;
 118
 119        struct mutex mount_mutex;      /* serialize mount attempts */
 120        wait_queue_head_t auth_wq;
 121        int auth_err;
 122
 123        int (*extra_mon_dispatch)(struct ceph_client *, struct ceph_msg *);
 124
 125        u32 supported_features;
 126        u32 required_features;
 127
 128        struct ceph_messenger msgr;   /* messenger instance */
 129        struct ceph_mon_client monc;
 130        struct ceph_osd_client osdc;
 131
 132#ifdef CONFIG_DEBUG_FS
 133        struct dentry *debugfs_dir;
 134        struct dentry *debugfs_monmap;
 135        struct dentry *debugfs_osdmap;
 136#endif
 137};
 138
 139
 140
 141/*
 142 * snapshots
 143 */
 144
 145/*
 146 * A "snap context" is the set of existing snapshots when we
 147 * write data.  It is used by the OSD to guide its COW behavior.
 148 *
 149 * The ceph_snap_context is refcounted, and attached to each dirty
 150 * page, indicating which context the dirty data belonged when it was
 151 * dirtied.
 152 */
 153struct ceph_snap_context {
 154        atomic_t nref;
 155        u64 seq;
 156        u32 num_snaps;
 157        u64 snaps[];
 158};
 159
 160extern struct ceph_snap_context *ceph_create_snap_context(u32 snap_count,
 161                                        gfp_t gfp_flags);
 162extern struct ceph_snap_context *ceph_get_snap_context(
 163                                        struct ceph_snap_context *sc);
 164extern void ceph_put_snap_context(struct ceph_snap_context *sc);
 165
 166/*
 167 * calculate the number of pages a given length and offset map onto,
 168 * if we align the data.
 169 */
 170static inline int calc_pages_for(u64 off, u64 len)
 171{
 172        return ((off+len+PAGE_CACHE_SIZE-1) >> PAGE_CACHE_SHIFT) -
 173                (off >> PAGE_CACHE_SHIFT);
 174}
 175
 176/* ceph_common.c */
 177extern bool libceph_compatible(void *data);
 178
 179extern const char *ceph_msg_type_name(int type);
 180extern int ceph_check_fsid(struct ceph_client *client, struct ceph_fsid *fsid);
 181extern struct kmem_cache *ceph_inode_cachep;
 182extern struct kmem_cache *ceph_cap_cachep;
 183extern struct kmem_cache *ceph_dentry_cachep;
 184extern struct kmem_cache *ceph_file_cachep;
 185
 186extern struct ceph_options *ceph_parse_options(char *options,
 187                              const char *dev_name, const char *dev_name_end,
 188                              int (*parse_extra_token)(char *c, void *private),
 189                              void *private);
 190extern void ceph_destroy_options(struct ceph_options *opt);
 191extern int ceph_compare_options(struct ceph_options *new_opt,
 192                                struct ceph_client *client);
 193extern struct ceph_client *ceph_create_client(struct ceph_options *opt,
 194                                              void *private,
 195                                              unsigned supported_features,
 196                                              unsigned required_features);
 197extern u64 ceph_client_id(struct ceph_client *client);
 198extern void ceph_destroy_client(struct ceph_client *client);
 199extern int __ceph_open_session(struct ceph_client *client,
 200                               unsigned long started);
 201extern int ceph_open_session(struct ceph_client *client);
 202
 203/* pagevec.c */
 204extern void ceph_release_page_vector(struct page **pages, int num_pages);
 205
 206extern struct page **ceph_get_direct_page_vector(const void __user *data,
 207                                                 int num_pages,
 208                                                 bool write_page);
 209extern void ceph_put_page_vector(struct page **pages, int num_pages,
 210                                 bool dirty);
 211extern void ceph_release_page_vector(struct page **pages, int num_pages);
 212extern struct page **ceph_alloc_page_vector(int num_pages, gfp_t flags);
 213extern int ceph_copy_user_to_page_vector(struct page **pages,
 214                                         const void __user *data,
 215                                         loff_t off, size_t len);
 216extern void ceph_copy_to_page_vector(struct page **pages,
 217                                    const void *data,
 218                                    loff_t off, size_t len);
 219extern void ceph_copy_from_page_vector(struct page **pages,
 220                                    void *data,
 221                                    loff_t off, size_t len);
 222extern int ceph_copy_page_vector_to_user(struct page **pages, void __user *data,
 223                                    loff_t off, size_t len);
 224extern void ceph_zero_page_vector_range(int off, int len, struct page **pages);
 225
 226
 227#endif /* _FS_CEPH_SUPER_H */
 228