include/linux/ceph/libceph.h

   1 #ifndef _FS_CEPH_LIBCEPH_H
   2 #define _FS_CEPH_LIBCEPH_H
   3
   4 #include "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/fs.h>
  11 #include <linux/mempool.h>
  12 #include <linux/pagemap.h>
  13 #include <linux/wait.h>
  14 #include <linux/writeback.h>
  15 #include <linux/slab.h>
  16
  17 #include "types.h"
  18 #include "messenger.h"
  19 #include "msgpool.h"
  20 #include "mon_client.h"
  21 #include "osd_client.h"
  22 #include "ceph_fs.h"
  23
  24 /*
  25  * Supported features
  26  */
  27 #define CEPH_FEATURE_SUPPORTED_DEFAULT CEPH_FEATURE_NOSRCADDR
  28 #define CEPH_FEATURE_REQUIRED_DEFAULT  CEPH_FEATURE_NOSRCADDR
  29
  30 /*
  31  * mount options
  32  */
  33 #define CEPH_OPT_FSID             (1<<0)
  34 #define CEPH_OPT_NOSHARE          (1<<1) /* don't share client with other sbs */
  35 #define CEPH_OPT_MYIP             (1<<2) /* specified my ip */
  36 #define CEPH_OPT_NOCRC            (1<<3) /* no data crc on writes */
  37
  38 #define CEPH_OPT_DEFAULT   (0)
  39
  40 #define ceph_set_opt(client, opt) \
  41         (client)->options->flags |= CEPH_OPT_##opt;
  42 #define ceph_test_opt(client, opt) \
  43         (!!((client)->options->flags & CEPH_OPT_##opt))
  44
  45 struct ceph_options {
  46         int flags;
  47         struct ceph_fsid fsid;
  48         struct ceph_entity_addr my_addr;
  49         int mount_timeout;
  50         int osd_idle_ttl;
  51         int osd_timeout;
  52         int osd_keepalive_timeout;
  53
  54         /*
  55          * any type that can't be simply compared or doesn't need need
  56          * to be compared should go beyond this point,
  57          * ceph_compare_options() should be updated accordingly
  58          */
  59
  60         struct ceph_entity_addr *mon_addr; /* should be the first
  61                                               pointer type of args */
  62         int num_mon;
  63         char *name;
  64         struct ceph_crypto_key *key;
  65 };
  66
  67 /*
  68  * defaults
  69  */
  70 #define CEPH_MOUNT_TIMEOUT_DEFAULT  60
  71 #define CEPH_OSD_TIMEOUT_DEFAULT    60  /* seconds */
  72 #define CEPH_OSD_KEEPALIVE_DEFAULT  5
  73 #define CEPH_OSD_IDLE_TTL_DEFAULT    60
  74
  75 #define CEPH_MSG_MAX_FRONT_LEN  (16*1024*1024)
  76 #define CEPH_MSG_MAX_DATA_LEN   (16*1024*1024)
  77
  78 #define CEPH_AUTH_NAME_DEFAULT   "guest"
  79
  80 /*
  81  * Delay telling the MDS we no longer want caps, in case we reopen
  82  * the file.  Delay a minimum amount of time, even if we send a cap
  83  * message for some other reason.  Otherwise, take the oppotunity to
  84  * update the mds to avoid sending another message later.
  85  */
  86 #define CEPH_CAPS_WANTED_DELAY_MIN_DEFAULT      5  /* cap release delay */
  87 #define CEPH_CAPS_WANTED_DELAY_MAX_DEFAULT     60  /* cap release delay */
  88
  89 #define CEPH_CAP_RELEASE_SAFETY_DEFAULT        (CEPH_CAPS_PER_RELEASE * 4)
  90
  91 /* mount state */
  92 enum {
  93         CEPH_MOUNT_MOUNTING,
  94         CEPH_MOUNT_MOUNTED,
  95         CEPH_MOUNT_UNMOUNTING,
  96         CEPH_MOUNT_UNMOUNTED,
  97         CEPH_MOUNT_SHUTDOWN,
  98 };
  99
 100 /*
 101  * subtract jiffies
 102  */
 103 static inline unsigned long time_sub(unsigned long a, unsigned long b)
 104 {
 105         BUG_ON(time_after(b, a));
 106         return (long)a - (long)b;
 107 }
 108
 109 struct ceph_mds_client;
 110
 111 /*
 112  * per client state
 113  *
 114  * possibly shared by multiple mount points, if they are
 115  * mounting the same ceph filesystem/cluster.
 116  */
 117 struct ceph_client {
 118         struct ceph_fsid fsid;
 119         bool have_fsid;
 120
 121         void *private;
 122
 123         struct ceph_options *options;
 124
 125         struct mutex mount_mutex;      /* serialize mount attempts */
 126         wait_queue_head_t auth_wq;
 127         int auth_err;
 128
 129         int (*extra_mon_dispatch)(struct ceph_client *, struct ceph_msg *);
 130
 131         u32 supported_features;
 132         u32 required_features;
 133
 134         struct ceph_messenger *msgr;   /* messenger instance */
 135         struct ceph_mon_client monc;
 136         struct ceph_osd_client osdc;
 137
 138 #ifdef CONFIG_DEBUG_FS
 139         struct dentry *debugfs_dir;
 140         struct dentry *debugfs_monmap;
 141         struct dentry *debugfs_osdmap;
 142 #endif
 143 };
 144
 145
 146
 147 /*
 148  * snapshots
 149  */
 150
 151 /*
 152  * A "snap context" is the set of existing snapshots when we
 153  * write data.  It is used by the OSD to guide its COW behavior.
 154  *
 155  * The ceph_snap_context is refcounted, and attached to each dirty
 156  * page, indicating which context the dirty data belonged when it was
 157  * dirtied.
 158  */
 159 struct ceph_snap_context {
 160         atomic_t nref;
 161         u64 seq;
 162         int num_snaps;
 163         u64 snaps[];
 164 };
 165
 166 static inline struct ceph_snap_context *
 167 ceph_get_snap_context(struct ceph_snap_context *sc)
 168 {
 169         /*
 170         printk("get_snap_context %p %d -> %d\n", sc, atomic_read(&sc->nref),
 171                atomic_read(&sc->nref)+1);
 172         */
 173         if (sc)
 174                 atomic_inc(&sc->nref);
 175         return sc;
 176 }
 177
 178 static inline void ceph_put_snap_context(struct ceph_snap_context *sc)
 179 {
 180         if (!sc)
 181                 return;
 182         /*
 183         printk("put_snap_context %p %d -> %d\n", sc, atomic_read(&sc->nref),
 184                atomic_read(&sc->nref)-1);
 185         */
 186         if (atomic_dec_and_test(&sc->nref)) {
 187                 /*printk(" deleting snap_context %p\n", sc);*/
 188                 kfree(sc);
 189         }
 190 }
 191
 192 /*
 193  * calculate the number of pages a given length and offset map onto,
 194  * if we align the data.
 195  */
 196 static inline int calc_pages_for(u64 off, u64 len)
 197 {
 198         return ((off+len+PAGE_CACHE_SIZE-1) >> PAGE_CACHE_SHIFT) -
 199                 (off >> PAGE_CACHE_SHIFT);
 200 }
 201
 202 /* ceph_common.c */
 203 extern const char *ceph_msg_type_name(int type);
 204 extern int ceph_check_fsid(struct ceph_client *client, struct ceph_fsid *fsid);
 205 extern struct kmem_cache *ceph_inode_cachep;
 206 extern struct kmem_cache *ceph_cap_cachep;
 207 extern struct kmem_cache *ceph_dentry_cachep;
 208 extern struct kmem_cache *ceph_file_cachep;
 209
 210 extern int ceph_parse_options(struct ceph_options **popt, char *options,
 211                               const char *dev_name, const char *dev_name_end,
 212                               int (*parse_extra_token)(char *c, void *private),
 213                               void *private);
 214 extern void ceph_destroy_options(struct ceph_options *opt);
 215 extern int ceph_compare_options(struct ceph_options *new_opt,
 216                                 struct ceph_client *client);
 217 extern struct ceph_client *ceph_create_client(struct ceph_options *opt,
 218                                               void *private,
 219                                               unsigned supported_features,
 220                                               unsigned required_features);
 221 extern u64 ceph_client_id(struct ceph_client *client);
 222 extern void ceph_destroy_client(struct ceph_client *client);
 223 extern int __ceph_open_session(struct ceph_client *client,
 224                                unsigned long started);
 225 extern int ceph_open_session(struct ceph_client *client);
 226
 227 /* pagevec.c */
 228 extern void ceph_release_page_vector(struct page **pages, int num_pages);
 229
 230 extern struct page **ceph_get_direct_page_vector(const char __user *data,
 231                                                  int num_pages,
 232                                                  bool write_page);
 233 extern void ceph_put_page_vector(struct page **pages, int num_pages,
 234                                  bool dirty);
 235 extern void ceph_release_page_vector(struct page **pages, int num_pages);
 236 extern struct page **ceph_alloc_page_vector(int num_pages, gfp_t flags);
 237 extern int ceph_copy_user_to_page_vector(struct page **pages,
 238                                          const char __user *data,
 239                                          loff_t off, size_t len);
 240 extern int ceph_copy_to_page_vector(struct page **pages,
 241                                     const char *data,
 242                                     loff_t off, size_t len);
 243 extern int ceph_copy_from_page_vector(struct page **pages,
 244                                     char *data,
 245                                     loff_t off, size_t len);
 246 extern int ceph_copy_page_vector_to_user(struct page **pages, char __user *data,
 247                                     loff_t off, size_t len);
 248 extern void ceph_zero_page_vector_range(int off, int len, struct page **pages);
 249
 250
 251 #endif /* _FS_CEPH_SUPER_H */