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
  40 struct 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_DATA_LEN   (16*1024*1024)
  70
  71 #define CEPH_AUTH_NAME_DEFAULT   "guest"
  72
  73 /*
  74  * Delay telling the MDS we no longer want caps, in case we reopen
  75  * the file.  Delay a minimum amount of time, even if we send a cap
  76  * message for some other reason.  Otherwise, take the oppotunity to
  77  * update the mds to avoid sending another message later.
  78  */
  79 #define CEPH_CAPS_WANTED_DELAY_MIN_DEFAULT      5  /* cap release delay */
  80 #define CEPH_CAPS_WANTED_DELAY_MAX_DEFAULT     60  /* cap release delay */
  81
  82 #define CEPH_CAP_RELEASE_SAFETY_DEFAULT        (CEPH_CAPS_PER_RELEASE * 4)
  83
  84 /* mount state */
  85 enum {
  86         CEPH_MOUNT_MOUNTING,
  87         CEPH_MOUNT_MOUNTED,
  88         CEPH_MOUNT_UNMOUNTING,
  89         CEPH_MOUNT_UNMOUNTED,
  90         CEPH_MOUNT_SHUTDOWN,
  91 };
  92
  93 /*
  94  * subtract jiffies
  95  */
  96 static inline unsigned long time_sub(unsigned long a, unsigned long b)
  97 {
  98         BUG_ON(time_after(b, a));
  99         return (long)a - (long)b;
 100 }
 101
 102 struct ceph_mds_client;
 103
 104 /*
 105  * per client state
 106  *
 107  * possibly shared by multiple mount points, if they are
 108  * mounting the same ceph filesystem/cluster.
 109  */
 110 struct ceph_client {
 111         struct ceph_fsid fsid;
 112         bool have_fsid;
 113
 114         void *private;
 115
 116         struct ceph_options *options;
 117
 118         struct mutex mount_mutex;      /* serialize mount attempts */
 119         wait_queue_head_t auth_wq;
 120         int auth_err;
 121
 122         int (*extra_mon_dispatch)(struct ceph_client *, struct ceph_msg *);
 123
 124         u32 supported_features;
 125         u32 required_features;
 126
 127         struct ceph_messenger msgr;   /* messenger instance */
 128         struct ceph_mon_client monc;
 129         struct ceph_osd_client osdc;
 130
 131 #ifdef CONFIG_DEBUG_FS
 132         struct dentry *debugfs_dir;
 133         struct dentry *debugfs_monmap;
 134         struct dentry *debugfs_osdmap;
 135 #endif
 136 };
 137
 138
 139
 140 /*
 141  * snapshots
 142  */
 143
 144 /*
 145  * A "snap context" is the set of existing snapshots when we
 146  * write data.  It is used by the OSD to guide its COW behavior.
 147  *
 148  * The ceph_snap_context is refcounted, and attached to each dirty
 149  * page, indicating which context the dirty data belonged when it was
 150  * dirtied.
 151  */
 152 struct ceph_snap_context {
 153         atomic_t nref;
 154         u64 seq;
 155         u32 num_snaps;
 156         u64 snaps[];
 157 };
 158
 159 static inline struct ceph_snap_context *
 160 ceph_get_snap_context(struct ceph_snap_context *sc)
 161 {
 162         /*
 163         printk("get_snap_context %p %d -> %d\n", sc, atomic_read(&sc->nref),
 164                atomic_read(&sc->nref)+1);
 165         */
 166         if (sc)
 167                 atomic_inc(&sc->nref);
 168         return sc;
 169 }
 170
 171 static inline void ceph_put_snap_context(struct ceph_snap_context *sc)
 172 {
 173         if (!sc)
 174                 return;
 175         /*
 176         printk("put_snap_context %p %d -> %d\n", sc, atomic_read(&sc->nref),
 177                atomic_read(&sc->nref)-1);
 178         */
 179         if (atomic_dec_and_test(&sc->nref)) {
 180                 /*printk(" deleting snap_context %p\n", sc);*/
 181                 kfree(sc);
 182         }
 183 }
 184
 185 /*
 186  * calculate the number of pages a given length and offset map onto,
 187  * if we align the data.
 188  */
 189 static inline int calc_pages_for(u64 off, u64 len)
 190 {
 191         return ((off+len+PAGE_CACHE_SIZE-1) >> PAGE_CACHE_SHIFT) -
 192                 (off >> PAGE_CACHE_SHIFT);
 193 }
 194
 195 /* ceph_common.c */
 196 extern bool libceph_compatible(void *data);
 197
 198 extern const char *ceph_msg_type_name(int type);
 199 extern int ceph_check_fsid(struct ceph_client *client, struct ceph_fsid *fsid);
 200 extern struct kmem_cache *ceph_inode_cachep;
 201 extern struct kmem_cache *ceph_cap_cachep;
 202 extern struct kmem_cache *ceph_dentry_cachep;
 203 extern struct kmem_cache *ceph_file_cachep;
 204
 205 extern struct ceph_options *ceph_parse_options(char *options,
 206                               const char *dev_name, const char *dev_name_end,
 207                               int (*parse_extra_token)(char *c, void *private),
 208                               void *private);
 209 extern void ceph_destroy_options(struct ceph_options *opt);
 210 extern int ceph_compare_options(struct ceph_options *new_opt,
 211                                 struct ceph_client *client);
 212 extern struct ceph_client *ceph_create_client(struct ceph_options *opt,
 213                                               void *private,
 214                                               unsigned supported_features,
 215                                               unsigned required_features);
 216 extern u64 ceph_client_id(struct ceph_client *client);
 217 extern void ceph_destroy_client(struct ceph_client *client);
 218 extern int __ceph_open_session(struct ceph_client *client,
 219                                unsigned long started);
 220 extern int ceph_open_session(struct ceph_client *client);
 221
 222 /* pagevec.c */
 223 extern void ceph_release_page_vector(struct page **pages, int num_pages);
 224
 225 extern struct page **ceph_get_direct_page_vector(const void __user *data,
 226                                                  int num_pages,
 227                                                  bool write_page);
 228 extern void ceph_put_page_vector(struct page **pages, int num_pages,
 229                                  bool dirty);
 230 extern void ceph_release_page_vector(struct page **pages, int num_pages);
 231 extern struct page **ceph_alloc_page_vector(int num_pages, gfp_t flags);
 232 extern int ceph_copy_user_to_page_vector(struct page **pages,
 233                                          const void __user *data,
 234                                          loff_t off, size_t len);
 235 extern void ceph_copy_to_page_vector(struct page **pages,
 236                                     const void *data,
 237                                     loff_t off, size_t len);
 238 extern void ceph_copy_from_page_vector(struct page **pages,
 239                                     void *data,
 240                                     loff_t off, size_t len);
 241 extern int ceph_copy_page_vector_to_user(struct page **pages, void __user *data,
 242                                     loff_t off, size_t len);
 243 extern void ceph_zero_page_vector_range(int off, int len, struct page **pages);
 244
 245
 246 #endif /* _FS_CEPH_SUPER_H */