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