ceph: factor out libceph from Ceph file system

This factors out protocol and low-level storage parts of ceph into a
separate libceph module living in net/ceph and include/linux/ceph.  This
is mostly a matter of moving files around.  However, a few key pieces
of the interface change as well:

 - ceph_client becomes ceph_fs_client and ceph_client, where the latter
   captures the mon and osd clients, and the fs_client gets the mds client
   and file system specific pieces.
 - Mount option parsing and debugfs setup is correspondingly broken into
   two pieces.
 - The mon client gets a generic handler callback for otherwise unknown
   messages (mds map, in this case).
 - The basic supported/required feature bits can be expanded (and are by
   ceph_fs_client).

No functional change, aside from some subtle error handling cases that got
cleaned up in the refactoring process.

Signed-off-by: Sage Weil <sage@newdream.net>

1 files changed, 143 insertions, 254 deletions

diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index b87638e84c4b..e2e904442ce2 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -1,7 +1,7 @@
 #ifndef _FS_CEPH_SUPER_H
 #define _FS_CEPH_SUPER_H
 
-#include "ceph_debug.h"
+#include <linux/ceph/ceph_debug.h>
 
 #include <asm/unaligned.h>
 #include <linux/backing-dev.h>
@@ -14,13 +14,7 @@
 #include <linux/writeback.h>
 #include <linux/slab.h>
 
-#include "types.h"
-#include "messenger.h"
-#include "msgpool.h"
-#include "mon_client.h"
-#include "mds_client.h"
-#include "osd_client.h"
-#include "ceph_fs.h"
+#include <linux/ceph/libceph.h>
 
 /* f_type in struct statfs */
 #define CEPH_SUPER_MAGIC 0x00c36400
@@ -30,42 +24,25 @@
 #define CEPH_BLOCK_SHIFT   20  /* 1 MB */
 #define CEPH_BLOCK         (1 << CEPH_BLOCK_SHIFT)
 
-/*
- * Supported features
- */
-#define CEPH_FEATURE_SUPPORTED CEPH_FEATURE_NOSRCADDR | CEPH_FEATURE_FLOCK
-#define CEPH_FEATURE_REQUIRED  CEPH_FEATURE_NOSRCADDR
+#define CEPH_MOUNT_OPT_DIRSTAT         (1<<4) /* `cat dirname` for stats */
+#define CEPH_MOUNT_OPT_RBYTES          (1<<5) /* dir st_bytes = rbytes */
+#define CEPH_MOUNT_OPT_NOASYNCREADDIR  (1<<7) /* no dcache readdir */
 
-/*
- * mount options
- */
-#define CEPH_OPT_FSID             (1<<0)
-#define CEPH_OPT_NOSHARE          (1<<1) /* don't share client with other sbs */
-#define CEPH_OPT_MYIP             (1<<2) /* specified my ip */
-#define CEPH_OPT_DIRSTAT          (1<<4) /* funky `cat dirname` for stats */
-#define CEPH_OPT_RBYTES           (1<<5) /* dir st_bytes = rbytes */
-#define CEPH_OPT_NOCRC            (1<<6) /* no data crc on writes */
-#define CEPH_OPT_NOASYNCREADDIR   (1<<7) /* no dcache readdir */
+#define CEPH_MOUNT_OPT_DEFAULT    (CEPH_MOUNT_OPT_RBYTES)
 
-#define CEPH_OPT_DEFAULT   (CEPH_OPT_RBYTES)
+#define ceph_set_mount_opt(fsc, opt) \
+        (fsc)->mount_options->flags |= CEPH_MOUNT_OPT_##opt;
+#define ceph_test_mount_opt(fsc, opt) \
+        (!!((fsc)->mount_options->flags & CEPH_MOUNT_OPT_##opt))
 
-#define ceph_set_opt(client, opt) \
-        (client)->mount_args->flags |= CEPH_OPT_##opt;
-#define ceph_test_opt(client, opt) \
-        (!!((client)->mount_args->flags & CEPH_OPT_##opt))
+#define CEPH_MAX_READDIR_DEFAULT        1024
+#define CEPH_MAX_READDIR_BYTES_DEFAULT  (512*1024)
+#define CEPH_SNAPDIRNAME_DEFAULT        ".snap"
 
-
-struct ceph_mount_args {
-        int sb_flags;
+struct ceph_mount_options {
         int flags;
-        struct ceph_fsid fsid;
-        struct ceph_entity_addr my_addr;
-        int num_mon;
-        struct ceph_entity_addr *mon_addr;
-        int mount_timeout;
-        int osd_idle_ttl;
-        int osd_timeout;
-        int osd_keepalive_timeout;
+        int sb_flags;
+
         int wsize;
         int rsize;            /* max readahead */
         int congestion_kb;    /* max writeback in flight */
@@ -73,82 +50,25 @@ struct ceph_mount_args {
         int cap_release_safety;
         int max_readdir;       /* max readdir result (entires) */
         int max_readdir_bytes; /* max readdir result (bytes) */
-        char *snapdir_name;   /* default ".snap" */
-        char *name;
-        char *secret;
-};
-
-/*
- * defaults
- */
-#define CEPH_MOUNT_TIMEOUT_DEFAULT  60
-#define CEPH_OSD_TIMEOUT_DEFAULT    60  /* seconds */
-#define CEPH_OSD_KEEPALIVE_DEFAULT  5
-#define CEPH_OSD_IDLE_TTL_DEFAULT    60
-#define CEPH_MOUNT_RSIZE_DEFAULT    (512*1024) /* readahead */
-#define CEPH_MAX_READDIR_DEFAULT    1024
-#define CEPH_MAX_READDIR_BYTES_DEFAULT    (512*1024)
-
-#define CEPH_MSG_MAX_FRONT_LEN  (16*1024*1024)
-#define CEPH_MSG_MAX_DATA_LEN   (16*1024*1024)
-
-#define CEPH_SNAPDIRNAME_DEFAULT ".snap"
-#define CEPH_AUTH_NAME_DEFAULT   "guest"
-/*
- * Delay telling the MDS we no longer want caps, in case we reopen
- * the file.  Delay a minimum amount of time, even if we send a cap
- * message for some other reason.  Otherwise, take the oppotunity to
- * update the mds to avoid sending another message later.
- */
-#define CEPH_CAPS_WANTED_DELAY_MIN_DEFAULT      5  /* cap release delay */
-#define CEPH_CAPS_WANTED_DELAY_MAX_DEFAULT     60  /* cap release delay */
-
-#define CEPH_CAP_RELEASE_SAFETY_DEFAULT        (CEPH_CAPS_PER_RELEASE * 4)
-
-/* mount state */
-enum {
-        CEPH_MOUNT_MOUNTING,
-        CEPH_MOUNT_MOUNTED,
-        CEPH_MOUNT_UNMOUNTING,
-        CEPH_MOUNT_UNMOUNTED,
-        CEPH_MOUNT_SHUTDOWN,
-};
 
-/*
- * subtract jiffies
- */
-static inline unsigned long time_sub(unsigned long a, unsigned long b)
-{
-        BUG_ON(time_after(b, a));
-        return (long)a - (long)b;
-}
-
-/*
- * per-filesystem client state
- *
- * possibly shared by multiple mount points, if they are
- * mounting the same ceph filesystem/cluster.
- */
-struct ceph_client {
-        struct ceph_fsid fsid;
-        bool have_fsid;
+        /*
+         * everything above this point can be memcmp'd; everything below
+         * is handled in compare_mount_options()
+         */
 
-        struct mutex mount_mutex;       /* serialize mount attempts */
-        struct ceph_mount_args *mount_args;
+        char *snapdir_name;   /* default ".snap" */
+};
 
+struct ceph_fs_client {
         struct super_block *sb;
 
-        unsigned long mount_state;
-        wait_queue_head_t auth_wq;
-
-        int auth_err;
+        struct ceph_mount_options *mount_options;
+        struct ceph_client *client;
 
+        unsigned long mount_state;
         int min_caps;                  /* min caps i added */
 
-        struct ceph_messenger *msgr;   /* messenger instance */
-        struct ceph_mon_client monc;
-        struct ceph_mds_client mdsc;
-        struct ceph_osd_client osdc;
+        struct ceph_mds_client *mdsc;
 
         /* writeback */
         mempool_t *wb_pagevec_pool;
@@ -160,14 +80,14 @@ struct ceph_client {
         struct backing_dev_info backing_dev_info;
 
 #ifdef CONFIG_DEBUG_FS
-        struct dentry *debugfs_monmap;
-        struct dentry *debugfs_mdsmap, *debugfs_osdmap;
-        struct dentry *debugfs_dir, *debugfs_dentry_lru, *debugfs_caps;
+        struct dentry *debugfs_dentry_lru, *debugfs_caps;
         struct dentry *debugfs_congestion_kb;
         struct dentry *debugfs_bdi;
+        struct dentry *debugfs_mdsc, *debugfs_mdsmap;
 #endif
 };
 
+
 /*
  * File i/o capability.  This tracks shared state with the metadata
  * server that allows us to cache or writeback attributes or to read
@@ -275,6 +195,20 @@ struct ceph_inode_xattr {
         int should_free_val;
 };
 
+/*
+ * Ceph dentry state
+ */
+struct ceph_dentry_info {
+        struct ceph_mds_session *lease_session;
+        u32 lease_gen, lease_shared_gen;
+        u32 lease_seq;
+        unsigned long lease_renew_after, lease_renew_from;
+        struct list_head lru;
+        struct dentry *dentry;
+        u64 time;
+        u64 offset;
+};
+
 struct ceph_inode_xattrs_info {
         /*
          * (still encoded) xattr blob. we avoid the overhead of parsing
@@ -296,11 +230,6 @@ struct ceph_inode_xattrs_info {
 /*
  * Ceph inode.
  */
-#define CEPH_I_COMPLETE  1  /* we have complete directory cached */
-#define CEPH_I_NODELAY   4  /* do not delay cap release */
-#define CEPH_I_FLUSH     8  /* do not delay flush of dirty metadata */
-#define CEPH_I_NOFLUSH  16  /* do not flush dirty caps */
-
 struct ceph_inode_info {
         struct ceph_vino i_vino;   /* ceph ino + snap */
 
@@ -391,6 +320,63 @@ static inline struct ceph_inode_info *ceph_inode(struct inode *inode)
         return container_of(inode, struct ceph_inode_info, vfs_inode);
 }
 
+static inline struct ceph_vino ceph_vino(struct inode *inode)
+{
+        return ceph_inode(inode)->i_vino;
+}
+
+/*
+ * ino_t is <64 bits on many architectures, blech.
+ *
+ * don't include snap in ino hash, at least for now.
+ */
+static inline ino_t ceph_vino_to_ino(struct ceph_vino vino)
+{
+        ino_t ino = (ino_t)vino.ino;  /* ^ (vino.snap << 20); */
+#if BITS_PER_LONG == 32
+        ino ^= vino.ino >> (sizeof(u64)-sizeof(ino_t)) * 8;
+        if (!ino)
+                ino = 1;
+#endif
+        return ino;
+}
+
+/* for printf-style formatting */
+#define ceph_vinop(i) ceph_inode(i)->i_vino.ino, ceph_inode(i)->i_vino.snap
+
+static inline u64 ceph_ino(struct inode *inode)
+{
+        return ceph_inode(inode)->i_vino.ino;
+}
+static inline u64 ceph_snap(struct inode *inode)
+{
+        return ceph_inode(inode)->i_vino.snap;
+}
+
+static inline int ceph_ino_compare(struct inode *inode, void *data)
+{
+        struct ceph_vino *pvino = (struct ceph_vino *)data;
+        struct ceph_inode_info *ci = ceph_inode(inode);
+        return ci->i_vino.ino == pvino->ino &&
+                ci->i_vino.snap == pvino->snap;
+}
+
+static inline struct inode *ceph_find_inode(struct super_block *sb,
+                                            struct ceph_vino vino)
+{
+        ino_t t = ceph_vino_to_ino(vino);
+        return ilookup5(sb, t, ceph_ino_compare, &vino);
+}
+
+
+/*
+ * Ceph inode.
+ */
+#define CEPH_I_COMPLETE  1  /* we have complete directory cached */
+#define CEPH_I_NODELAY   4  /* do not delay cap release */
+#define CEPH_I_FLUSH     8  /* do not delay flush of dirty metadata */
+#define CEPH_I_NOFLUSH  16  /* do not flush dirty caps */
+
 static inline void ceph_i_clear(struct inode *inode, unsigned mask)
 {
         struct ceph_inode_info *ci = ceph_inode(inode);
@@ -432,20 +418,6 @@ extern u32 ceph_choose_frag(struct ceph_inode_info *ci, u32 v,
                             struct ceph_inode_frag *pfrag,
                             int *found);
 
-/*
- * Ceph dentry state
- */
-struct ceph_dentry_info {
-        struct ceph_mds_session *lease_session;
-        u32 lease_gen, lease_shared_gen;
-        u32 lease_seq;
-        unsigned long lease_renew_after, lease_renew_from;
-        struct list_head lru;
-        struct dentry *dentry;
-        u64 time;
-        u64 offset;
-};
-
 static inline struct ceph_dentry_info *ceph_dentry(struct dentry *dentry)
 {
         return (struct ceph_dentry_info *)dentry->d_fsdata;
@@ -456,22 +428,6 @@ static inline loff_t ceph_make_fpos(unsigned frag, unsigned off)
         return ((loff_t)frag << 32) | (loff_t)off;
 }
 
-/*
- * ino_t is <64 bits on many architectures, blech.
- *
- * don't include snap in ino hash, at least for now.
- */
-static inline ino_t ceph_vino_to_ino(struct ceph_vino vino)
-{
-        ino_t ino = (ino_t)vino.ino;  /* ^ (vino.snap << 20); */
-#if BITS_PER_LONG == 32
-        ino ^= vino.ino >> (sizeof(u64)-sizeof(ino_t)) * 8;
-        if (!ino)
-                ino = 1;
-#endif
-        return ino;
-}
-
 static inline int ceph_set_ino_cb(struct inode *inode, void *data)
 {
         ceph_inode(inode)->i_vino = *(struct ceph_vino *)data;
@@ -479,39 +435,6 @@ static inline int ceph_set_ino_cb(struct inode *inode, void *data)
         return 0;
 }
 
-static inline struct ceph_vino ceph_vino(struct inode *inode)
-{
-        return ceph_inode(inode)->i_vino;
-}
-
-/* for printf-style formatting */
-#define ceph_vinop(i) ceph_inode(i)->i_vino.ino, ceph_inode(i)->i_vino.snap
-
-static inline u64 ceph_ino(struct inode *inode)
-{
-        return ceph_inode(inode)->i_vino.ino;
-}
-static inline u64 ceph_snap(struct inode *inode)
-{
-        return ceph_inode(inode)->i_vino.snap;
-}
-
-static inline int ceph_ino_compare(struct inode *inode, void *data)
-{
-        struct ceph_vino *pvino = (struct ceph_vino *)data;
-        struct ceph_inode_info *ci = ceph_inode(inode);
-        return ci->i_vino.ino == pvino->ino &&
-                ci->i_vino.snap == pvino->snap;
-}
-
-static inline struct inode *ceph_find_inode(struct super_block *sb,
-                                            struct ceph_vino vino)
-{
-        ino_t t = ceph_vino_to_ino(vino);
-        return ilookup5(sb, t, ceph_ino_compare, &vino);
-}
-
-
 /*
  * caps helpers
  */
@@ -576,18 +499,18 @@ extern int ceph_reserve_caps(struct ceph_mds_client *mdsc,
                              struct ceph_cap_reservation *ctx, int need);
 extern int ceph_unreserve_caps(struct ceph_mds_client *mdsc,
                                struct ceph_cap_reservation *ctx);
-extern void ceph_reservation_status(struct ceph_client *client,
+extern void ceph_reservation_status(struct ceph_fs_client *client,
                                     int *total, int *avail, int *used,
                                     int *reserved, int *min);
 
-static inline struct ceph_client *ceph_inode_to_client(struct inode *inode)
+static inline struct ceph_fs_client *ceph_inode_to_client(struct inode *inode)
 {
-        return (struct ceph_client *)inode->i_sb->s_fs_info;
+        return (struct ceph_fs_client *)inode->i_sb->s_fs_info;
 }
 
-static inline struct ceph_client *ceph_sb_to_client(struct super_block *sb)
+static inline struct ceph_fs_client *ceph_sb_to_client(struct super_block *sb)
 {
-        return (struct ceph_client *)sb->s_fs_info;
+        return (struct ceph_fs_client *)sb->s_fs_info;
 }
 
 
@@ -617,51 +540,6 @@ struct ceph_file_info {
 
 
 /*
- * snapshots
- */
-
-/*
- * A "snap context" is the set of existing snapshots when we
- * write data.  It is used by the OSD to guide its COW behavior.
- *
- * The ceph_snap_context is refcounted, and attached to each dirty
- * page, indicating which context the dirty data belonged when it was
- * dirtied.
- */
-struct ceph_snap_context {
-        atomic_t nref;
-        u64 seq;
-        int num_snaps;
-        u64 snaps[];
-};
-
-static inline struct ceph_snap_context *
-ceph_get_snap_context(struct ceph_snap_context *sc)
-{
-        /*
-        printk("get_snap_context %p %d -> %d\n", sc, atomic_read(&sc->nref),
-               atomic_read(&sc->nref)+1);
-        */
-        if (sc)
-                atomic_inc(&sc->nref);
-        return sc;
-}
-
-static inline void ceph_put_snap_context(struct ceph_snap_context *sc)
-{
-        if (!sc)
-                return;
-        /*
-        printk("put_snap_context %p %d -> %d\n", sc, atomic_read(&sc->nref),
-               atomic_read(&sc->nref)-1);
-        */
-        if (atomic_dec_and_test(&sc->nref)) {
-                /*printk(" deleting snap_context %p\n", sc);*/
-                kfree(sc);
-        }
-}
-
-/*
  * A "snap realm" describes a subset of the file hierarchy sharing
  * the same set of snapshots that apply to it.  The realms themselves
  * are organized into a hierarchy, such that children inherit (some of)
@@ -699,16 +577,33 @@ struct ceph_snap_realm {
         spinlock_t inodes_with_caps_lock;
 };
 
-
-
-/*
- * calculate the number of pages a given length and offset map onto,
- * if we align the data.
- */
-static inline int calc_pages_for(u64 off, u64 len)
+static inline int default_congestion_kb(void)
 {
-        return ((off+len+PAGE_CACHE_SIZE-1) >> PAGE_CACHE_SHIFT) -
-                (off >> PAGE_CACHE_SHIFT);
+        int congestion_kb;
+
+        /*
+         * Copied from NFS
+         *
+         * congestion size, scale with available memory.
+         *
+         *  64MB:    8192k
+         * 128MB:   11585k
+         * 256MB:   16384k
+         * 512MB:   23170k
+         *   1GB:   32768k
+         *   2GB:   46340k
+         *   4GB:   65536k
+         *   8GB:   92681k
+         *  16GB:  131072k
+         *
+         * This allows larger machines to have larger/more transfers.
+         * Limit the default to 256M
+         */
+        congestion_kb = (16*int_sqrt(totalram_pages)) << (PAGE_SHIFT-10);
+        if (congestion_kb > 256*1024)
+                congestion_kb = 256*1024;
+
+        return congestion_kb;
 }
 
 
@@ -741,16 +636,6 @@ static inline bool __ceph_have_pending_cap_snap(struct ceph_inode_info *ci)
                            ci_item)->writing;
 }
 
-
-/* super.c */
-extern struct kmem_cache *ceph_inode_cachep;
-extern struct kmem_cache *ceph_cap_cachep;
-extern struct kmem_cache *ceph_dentry_cachep;
-extern struct kmem_cache *ceph_file_cachep;
-
-extern const char *ceph_msg_type_name(int type);
-extern int ceph_check_fsid(struct ceph_client *client, struct ceph_fsid *fsid);
-
 /* inode.c */
 extern const struct inode_operations ceph_file_iops;
 
@@ -857,12 +742,18 @@ extern int ceph_mmap(struct file *file, struct vm_area_struct *vma);
 /* file.c */
 extern const struct file_operations ceph_file_fops;
 extern const struct address_space_operations ceph_aops;
+extern int ceph_copy_to_page_vector(struct page **pages,
+                                    const char *data,
+                                    loff_t off, size_t len);
+extern int ceph_copy_from_page_vector(struct page **pages,
+                                    char *data,
+                                    loff_t off, size_t len);
+extern struct page **ceph_alloc_page_vector(int num_pages, gfp_t flags);
 extern int ceph_open(struct inode *inode, struct file *file);
 extern struct dentry *ceph_lookup_open(struct inode *dir, struct dentry *dentry,
                                        struct nameidata *nd, int mode,
                                        int locked_dir);
 extern int ceph_release(struct inode *inode, struct file *filp);
-extern void ceph_release_page_vector(struct page **pages, int num_pages);
 
 /* dir.c */
 extern const struct file_operations ceph_dir_fops;
@@ -892,12 +783,6 @@ extern long ceph_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
 /* export.c */
 extern const struct export_operations ceph_export_ops;
 
-/* debugfs.c */
-extern int ceph_debugfs_init(void);
-extern void ceph_debugfs_cleanup(void);
-extern int ceph_debugfs_client_init(struct ceph_client *client);
-extern void ceph_debugfs_client_cleanup(struct ceph_client *client);
-
 /* locks.c */
 extern int ceph_lock(struct file *file, int cmd, struct file_lock *fl);
 extern int ceph_flock(struct file *file, int cmd, struct file_lock *fl);
@@ -914,4 +799,8 @@ static inline struct inode *get_dentry_parent_inode(struct dentry *dentry)
         return NULL;
 }
 
+/* debugfs.c */
+extern int ceph_fs_debugfs_init(struct ceph_fs_client *client);
+extern void ceph_fs_debugfs_cleanup(struct ceph_fs_client *client);
+
 #endif /* _FS_CEPH_SUPER_H */