fscache: Attach the index key and aux data to the cookie
Attach copies of the index key and auxiliary data to the fscache cookie so
that:
(1) The callbacks to the netfs for this stuff can be eliminated. This
can simplify things in the cache as the information is still
available, even after the cache has relinquished the cookie.
(2) Simplifies the locking requirements of accessing the information as we
don't have to worry about the netfs object going away on us.
(3) The cache can do lazy updating of the coherency information on disk.
As long as the cache is flushed before reboot/poweroff, there's no
need to update the coherency info on disk every time it changes.
(4) Cookies can be hashed or put in a tree as the index key is easily
available. This allows:
(a) Checks for duplicate cookies can be made at the top fscache layer
rather than down in the bowels of the cache backend.
(b) Caching can be added to a netfs object that has a cookie if the
cache is brought online after the netfs object is allocated.
A certain amount of space is made in the cookie for inline copies of the
data, but if it won't fit there, extra memory will be allocated for it.
The downside of this is that live cache operation requires more memory.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Anna Schumaker <anna.schumaker@netapp.com>
Tested-by: Steve Dickson <steved@redhat.com>
diff --git a/fs/cifs/cache.c b/fs/cifs/cache.c
index 2c14020..b4fa270 100644
--- a/fs/cifs/cache.c
+++ b/fs/cifs/cache.c
@@ -46,67 +46,11 @@ void cifs_fscache_unregister(void)
}
/*
- * Key layout of CIFS server cache index object
- */
-struct cifs_server_key {
- uint16_t family; /* address family */
- __be16 port; /* IP port */
- union {
- struct in_addr ipv4_addr;
- struct in6_addr ipv6_addr;
- } addr[0];
-};
-
-/*
- * Server object keyed by {IPaddress,port,family} tuple
- */
-static uint16_t cifs_server_get_key(const void *cookie_netfs_data,
- void *buffer, uint16_t maxbuf)
-{
- const struct TCP_Server_Info *server = cookie_netfs_data;
- const struct sockaddr *sa = (struct sockaddr *) &server->dstaddr;
- const struct sockaddr_in *addr = (struct sockaddr_in *) sa;
- const struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *) sa;
- struct cifs_server_key *key = buffer;
- uint16_t key_len = sizeof(struct cifs_server_key);
-
- memset(key, 0, key_len);
-
- /*
- * Should not be a problem as sin_family/sin6_family overlays
- * sa_family field
- */
- switch (sa->sa_family) {
- case AF_INET:
- key->family = sa->sa_family;
- key->port = addr->sin_port;
- key->addr[0].ipv4_addr = addr->sin_addr;
- key_len += sizeof(key->addr[0].ipv4_addr);
- break;
-
- case AF_INET6:
- key->family = sa->sa_family;
- key->port = addr6->sin6_port;
- key->addr[0].ipv6_addr = addr6->sin6_addr;
- key_len += sizeof(key->addr[0].ipv6_addr);
- break;
-
- default:
- cifs_dbg(VFS, "Unknown network family '%d'\n", sa->sa_family);
- key_len = 0;
- break;
- }
-
- return key_len;
-}
-
-/*
* Server object for FS-Cache
*/
const struct fscache_cookie_def cifs_fscache_server_index_def = {
.name = "CIFS.server",
.type = FSCACHE_COOKIE_TYPE_INDEX,
- .get_key = cifs_server_get_key,
};
/*
@@ -116,7 +60,7 @@ struct cifs_fscache_super_auxdata {
u64 resource_id; /* unique server resource id */
};
-static char *extract_sharename(const char *treename)
+char *extract_sharename(const char *treename)
{
const char *src;
char *delim, *dst;
@@ -140,52 +84,6 @@ static char *extract_sharename(const char *treename)
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 cifs_tcon *tcon = cookie_netfs_data;
- char *sharename;
- uint16_t len;
-
- sharename = extract_sharename(tcon->treeName);
- if (IS_ERR(sharename)) {
- cifs_dbg(FYI, "%s: couldn't extract sharename\n", __func__);
- 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 cifs_tcon *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,
@@ -212,36 +110,9 @@ fscache_checkaux cifs_fscache_super_check_aux(void *cookie_netfs_data,
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,
};
-/*
- * Auxiliary data attached to CIFS inode within the cache
- */
-struct cifs_fscache_inode_auxdata {
- struct timespec last_write_time;
- struct timespec last_change_time;
- u64 eof;
-};
-
-static uint16_t cifs_fscache_inode_get_key(const void *cookie_netfs_data,
- void *buffer, uint16_t maxbuf)
-{
- const struct cifsInodeInfo *cifsi = cookie_netfs_data;
- uint16_t keylen;
-
- /* use the UniqueId as the key */
- keylen = sizeof(cifsi->uniqueid);
- if (keylen > maxbuf)
- keylen = 0;
- else
- memcpy(buffer, &cifsi->uniqueid, keylen);
-
- return keylen;
-}
-
static void
cifs_fscache_inode_get_attr(const void *cookie_netfs_data, uint64_t *size)
{
@@ -250,26 +121,6 @@ cifs_fscache_inode_get_attr(const void *cookie_netfs_data, uint64_t *size)
*size = cifsi->vfs_inode.i_size;
}
-static uint16_t
-cifs_fscache_inode_get_aux(const void *cookie_netfs_data, void *buffer,
- uint16_t maxbuf)
-{
- struct cifs_fscache_inode_auxdata auxdata;
- const struct cifsInodeInfo *cifsi = cookie_netfs_data;
-
- memset(&auxdata, 0, sizeof(auxdata));
- auxdata.eof = cifsi->server_eof;
- auxdata.last_write_time = cifsi->vfs_inode.i_mtime;
- auxdata.last_change_time = cifsi->vfs_inode.i_ctime;
-
- if (maxbuf > sizeof(auxdata))
- maxbuf = sizeof(auxdata);
-
- memcpy(buffer, &auxdata, maxbuf);
-
- return maxbuf;
-}
-
static enum
fscache_checkaux cifs_fscache_inode_check_aux(void *cookie_netfs_data,
const void *data,
@@ -295,8 +146,6 @@ fscache_checkaux cifs_fscache_inode_check_aux(void *cookie_netfs_data,
const struct fscache_cookie_def cifs_fscache_inode_object_def = {
.name = "CIFS.uniqueid",
.type = FSCACHE_COOKIE_TYPE_DATAFILE,
- .get_key = cifs_fscache_inode_get_key,
.get_attr = cifs_fscache_inode_get_attr,
- .get_aux = cifs_fscache_inode_get_aux,
.check_aux = cifs_fscache_inode_check_aux,
};