Define superblock-level cache index objects (managed by cifsTconInfo structs). Each superblock object is created in a server-level index object and in itself an index into which inode-level objects are inserted.
The superblock object is keyed by sharename. The UniqueId/IndexNumber is used to validate that the exported share is the same since we accessed it last time. Signed-off-by: Suresh Jayaraman <[email protected]> --- fs/cifs/cache.c | 109 +++++++++++++++++++++++++++++++++++++++++++++++++++++ fs/cifs/cifsglob.h | 4 + fs/cifs/connect.c | 3 + fs/cifs/fscache.c | 17 ++++++++ fs/cifs/fscache.h | 6 ++ fs/cifs/inode.c | 3 + 6 files changed, 142 insertions(+) Index: cifs-2.6/fs/cifs/cache.c =================================================================== --- cifs-2.6.orig/fs/cifs/cache.c +++ cifs-2.6/fs/cifs/cache.c @@ -106,3 +106,112 @@ const struct fscache_cookie_def cifs_fsc .type = FSCACHE_COOKIE_TYPE_INDEX, .get_key = cifs_server_get_key, }; + +/* + * Auxiliary data attached to CIFS superblock within the cache + */ +struct cifs_fscache_super_auxdata { + u64 resource_id; /* unique server resource id */ +}; + +static char *extract_sharename(const char *treename) +{ + const char *src; + char *delim, *dst; + int len; + + /* skip double chars at the beginning */ + src = treename + 2; + + /* share name is always preceded by '\\' now */ + delim = strchr(src, '\\'); + if (!delim) + return ERR_PTR(-EINVAL); + delim++; + len = strlen(delim); + + /* caller has to free the memory */ + dst = kstrndup(delim, len, GFP_KERNEL); + if (!dst) + return ERR_PTR(-ENOMEM); + + return dst; +} + +/* + * Superblock object currently keyed by share name + */ +static uint16_t cifs_super_get_key(const void *cookie_netfs_data, void *buffer, + uint16_t maxbuf) +{ + const struct cifsTconInfo *tcon = cookie_netfs_data; + char *sharename; + uint16_t len; + + sharename = extract_sharename(tcon->treeName); + if (IS_ERR(sharename)) { + cFYI(1, "CIFS: couldn't extract sharename\n"); + sharename = NULL; + return 0; + } + + len = strlen(sharename); + if (len > maxbuf) + return 0; + + memcpy(buffer, sharename, len); + + kfree(sharename); + + return len; +} + +static uint16_t +cifs_fscache_super_get_aux(const void *cookie_netfs_data, void *buffer, + uint16_t maxbuf) +{ + struct cifs_fscache_super_auxdata auxdata; + const struct cifsTconInfo *tcon = cookie_netfs_data; + + memset(&auxdata, 0, sizeof(auxdata)); + auxdata.resource_id = tcon->resource_id; + + if (maxbuf > sizeof(auxdata)) + maxbuf = sizeof(auxdata); + + memcpy(buffer, &auxdata, maxbuf); + + return maxbuf; +} + +static enum +fscache_checkaux cifs_fscache_super_check_aux(void *cookie_netfs_data, + const void *data, + uint16_t datalen) +{ + struct cifs_fscache_super_auxdata auxdata; + const struct cifsTconInfo *tcon = cookie_netfs_data; + + if (datalen != sizeof(auxdata)) + return FSCACHE_CHECKAUX_OBSOLETE; + + memset(&auxdata, 0, sizeof(auxdata)); + auxdata.resource_id = tcon->resource_id; + + if (memcmp(data, &auxdata, datalen) != 0) + return FSCACHE_CHECKAUX_OBSOLETE; + + return FSCACHE_CHECKAUX_OKAY; +} + +/* + * Superblock object for FS-Cache + */ +const struct fscache_cookie_def cifs_fscache_super_index_def = { + .name = "CIFS.super", + .type = FSCACHE_COOKIE_TYPE_INDEX, + .get_key = cifs_super_get_key, + .get_aux = cifs_fscache_super_get_aux, + .check_aux = cifs_fscache_super_check_aux, +}; + Index: cifs-2.6/fs/cifs/fscache.c =================================================================== --- cifs-2.6.orig/fs/cifs/fscache.c +++ cifs-2.6/fs/cifs/fscache.c @@ -39,3 +39,20 @@ void cifs_fscache_release_client_cookie( server->fscache = NULL; } +void cifs_fscache_get_super_cookie(struct cifsTconInfo *tcon) +{ + struct TCP_Server_Info *server = tcon->ses->server; + + tcon->fscache = + fscache_acquire_cookie(server->fscache, + &cifs_fscache_super_index_def, tcon); + cFYI(1, "CIFS: get superblock cookie (0x%p/0x%p)", + server->fscache, tcon->fscache); +} + +void cifs_fscache_release_super_cookie(struct cifsTconInfo *tcon) +{ + cFYI(1, "CIFS: releasing superblock cookie (0x%p)", tcon->fscache); + fscache_relinquish_cookie(tcon->fscache, 0); + tcon->fscache = NULL; +} Index: cifs-2.6/fs/cifs/fscache.h =================================================================== --- cifs-2.6.orig/fs/cifs/fscache.h +++ cifs-2.6/fs/cifs/fscache.h @@ -29,6 +29,7 @@ extern struct fscache_netfs cifs_fscache_netfs; extern const struct fscache_cookie_def cifs_fscache_server_index_def; +extern const struct fscache_cookie_def cifs_fscache_super_index_def; extern int cifs_fscache_register(void); extern void cifs_fscache_unregister(void); @@ -38,6 +39,8 @@ extern void cifs_fscache_unregister(void */ extern void cifs_fscache_get_client_cookie(struct TCP_Server_Info *); extern void cifs_fscache_release_client_cookie(struct TCP_Server_Info *); +extern void cifs_fscache_get_super_cookie(struct cifsTconInfo *); +extern void cifs_fscache_release_super_cookie(struct cifsTconInfo *); #else /* CONFIG_CIFS_FSCACHE */ static inline int cifs_fscache_register(void) { return 0; } @@ -47,6 +50,9 @@ static inline void cifs_fscache_get_client_cookie(struct TCP_Server_Info *server) {} static inline void cifs_fscache_get_client_cookie(struct TCP_Server_Info *server); {} +static inline void cifs_fscache_get_super_cookie(struct cifsTconInfo *tcon) {} +static inline void +cifs_fscache_release_super_cookie(struct cifsTconInfo *tcon) {} #endif /* CONFIG_CIFS_FSCACHE */ Index: cifs-2.6/fs/cifs/cifsglob.h =================================================================== --- cifs-2.6.orig/fs/cifs/cifsglob.h +++ cifs-2.6/fs/cifs/cifsglob.h @@ -314,6 +314,10 @@ struct cifsTconInfo { bool local_lease:1; /* check leases (only) on local system not remote */ bool broken_posix_open; /* e.g. Samba server versions < 3.3.2, 3.2.9 */ bool need_reconnect:1; /* connection reset, tid now invalid */ +#ifdef CONFIG_CIFS_FSCACHE + u64 resource_id; /* server resource id */ + struct fscache_cookie *fscache; /* cookie for share */ +#endif /* BB add field for back pointer to sb struct(s)? */ }; Index: cifs-2.6/fs/cifs/connect.c =================================================================== --- cifs-2.6.orig/fs/cifs/connect.c +++ cifs-2.6/fs/cifs/connect.c @@ -1779,6 +1779,7 @@ cifs_put_tcon(struct cifsTconInfo *tcon) _FreeXid(xid); tconInfoFree(tcon); + cifs_fscache_release_super_cookie(tcon); cifs_put_smb_ses(ses); } @@ -1848,6 +1849,8 @@ cifs_get_tcon(struct cifsSesInfo *ses, s list_add(&tcon->tcon_list, &ses->tcon_list); write_unlock(&cifs_tcp_ses_lock); + cifs_fscache_get_super_cookie(tcon); + return tcon; out_fail: Index: cifs-2.6/fs/cifs/inode.c =================================================================== --- cifs-2.6.orig/fs/cifs/inode.c +++ cifs-2.6/fs/cifs/inode.c @@ -807,6 +807,9 @@ struct inode *cifs_root_iget(struct supe if (!inode) return ERR_PTR(-ENOMEM); + /* populate tcon->resource_id */ + cifs_sb->tcon->resource_id = CIFS_I(inode)->uniqueid; + if (rc && cifs_sb->tcon->ipc) { cFYI(1, "ipc connection - fake read inode"); inode->i_mode |= S_IFDIR; -- To unsubscribe from this list: send the line "unsubscribe linux-cifs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
