~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/fs/nfs/fscache-index.c

Version: ~ [ linux-5.6-rc3 ] ~ [ linux-5.5.6 ] ~ [ linux-5.4.22 ] ~ [ linux-5.3.18 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.106 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.171 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.214 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.214 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.19.8 ] ~ [ linux-3.18.140 ] ~ [ linux-3.17.8 ] ~ [ linux-3.16.82 ] ~ [ linux-3.15.10 ] ~ [ linux-3.14.79 ] ~ [ linux-3.13.11 ] ~ [ linux-3.12.74 ] ~ [ linux-3.11.10 ] ~ [ linux-3.10.108 ] ~ [ linux-3.9.11 ] ~ [ linux-3.8.13 ] ~ [ linux-3.7.10 ] ~ [ linux-3.6.11 ] ~ [ linux-3.5.7 ] ~ [ linux-3.4.113 ] ~ [ linux-3.3.8 ] ~ [ linux-3.2.102 ] ~ [ linux-3.1.10 ] ~ [ linux-3.0.101 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  1 /* NFS FS-Cache index structure definition
  2  *
  3  * Copyright (C) 2008 Red Hat, Inc. All Rights Reserved.
  4  * Written by David Howells (dhowells@redhat.com)
  5  *
  6  * This program is free software; you can redistribute it and/or
  7  * modify it under the terms of the GNU General Public Licence
  8  * as published by the Free Software Foundation; either version
  9  * 2 of the Licence, or (at your option) any later version.
 10  */
 11 
 12 #include <linux/init.h>
 13 #include <linux/kernel.h>
 14 #include <linux/sched.h>
 15 #include <linux/mm.h>
 16 #include <linux/nfs_fs.h>
 17 #include <linux/nfs_fs_sb.h>
 18 #include <linux/in6.h>
 19 
 20 #include "internal.h"
 21 #include "fscache.h"
 22 
 23 #define NFSDBG_FACILITY         NFSDBG_FSCACHE
 24 
 25 /*
 26  * Define the NFS filesystem for FS-Cache.  Upon registration FS-Cache sticks
 27  * the cookie for the top-level index object for NFS into here.  The top-level
 28  * index can than have other cache objects inserted into it.
 29  */
 30 struct fscache_netfs nfs_fscache_netfs = {
 31         .name           = "nfs",
 32         .version        = 0,
 33 };
 34 
 35 /*
 36  * Register NFS for caching
 37  */
 38 int nfs_fscache_register(void)
 39 {
 40         return fscache_register_netfs(&nfs_fscache_netfs);
 41 }
 42 
 43 /*
 44  * Unregister NFS for caching
 45  */
 46 void nfs_fscache_unregister(void)
 47 {
 48         fscache_unregister_netfs(&nfs_fscache_netfs);
 49 }
 50 
 51 /*
 52  * Layout of the key for an NFS server cache object.
 53  */
 54 struct nfs_server_key {
 55         uint16_t        nfsversion;             /* NFS protocol version */
 56         uint16_t        family;                 /* address family */
 57         uint16_t        port;                   /* IP port */
 58         union {
 59                 struct in_addr  ipv4_addr;      /* IPv4 address */
 60                 struct in6_addr ipv6_addr;      /* IPv6 address */
 61         } addr[0];
 62 };
 63 
 64 /*
 65  * Generate a key to describe a server in the main NFS index
 66  * - We return the length of the key, or 0 if we can't generate one
 67  */
 68 static uint16_t nfs_server_get_key(const void *cookie_netfs_data,
 69                                    void *buffer, uint16_t bufmax)
 70 {
 71         const struct nfs_client *clp = cookie_netfs_data;
 72         const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) &clp->cl_addr;
 73         const struct sockaddr_in *sin = (struct sockaddr_in *) &clp->cl_addr;
 74         struct nfs_server_key *key = buffer;
 75         uint16_t len = sizeof(struct nfs_server_key);
 76 
 77         memset(key, 0, len);
 78         key->nfsversion = clp->rpc_ops->version;
 79         key->family = clp->cl_addr.ss_family;
 80 
 81         switch (clp->cl_addr.ss_family) {
 82         case AF_INET:
 83                 key->port = sin->sin_port;
 84                 key->addr[0].ipv4_addr = sin->sin_addr;
 85                 len += sizeof(key->addr[0].ipv4_addr);
 86                 break;
 87 
 88         case AF_INET6:
 89                 key->port = sin6->sin6_port;
 90                 key->addr[0].ipv6_addr = sin6->sin6_addr;
 91                 len += sizeof(key->addr[0].ipv6_addr);
 92                 break;
 93 
 94         default:
 95                 printk(KERN_WARNING "NFS: Unknown network family '%d'\n",
 96                        clp->cl_addr.ss_family);
 97                 len = 0;
 98                 break;
 99         }
100 
101         return len;
102 }
103 
104 /*
105  * Define the server object for FS-Cache.  This is used to describe a server
106  * object to fscache_acquire_cookie().  It is keyed by the NFS protocol and
107  * server address parameters.
108  */
109 const struct fscache_cookie_def nfs_fscache_server_index_def = {
110         .name           = "NFS.server",
111         .type           = FSCACHE_COOKIE_TYPE_INDEX,
112         .get_key        = nfs_server_get_key,
113 };
114 
115 /*
116  * Generate a key to describe a superblock key in the main NFS index
117  */
118 static uint16_t nfs_super_get_key(const void *cookie_netfs_data,
119                                   void *buffer, uint16_t bufmax)
120 {
121         const struct nfs_fscache_key *key;
122         const struct nfs_server *nfss = cookie_netfs_data;
123         uint16_t len;
124 
125         key = nfss->fscache_key;
126         len = sizeof(key->key) + key->key.uniq_len;
127         if (len > bufmax) {
128                 len = 0;
129         } else {
130                 memcpy(buffer, &key->key, sizeof(key->key));
131                 memcpy(buffer + sizeof(key->key),
132                        key->key.uniquifier, key->key.uniq_len);
133         }
134 
135         return len;
136 }
137 
138 /*
139  * Define the superblock object for FS-Cache.  This is used to describe a
140  * superblock object to fscache_acquire_cookie().  It is keyed by all the NFS
141  * parameters that might cause a separate superblock.
142  */
143 const struct fscache_cookie_def nfs_fscache_super_index_def = {
144         .name           = "NFS.super",
145         .type           = FSCACHE_COOKIE_TYPE_INDEX,
146         .get_key        = nfs_super_get_key,
147 };
148 
149 /*
150  * Definition of the auxiliary data attached to NFS inode storage objects
151  * within the cache.
152  *
153  * The contents of this struct are recorded in the on-disk local cache in the
154  * auxiliary data attached to the data storage object backing an inode.  This
155  * permits coherency to be managed when a new inode binds to an already extant
156  * cache object.
157  */
158 struct nfs_fscache_inode_auxdata {
159         struct timespec mtime;
160         struct timespec ctime;
161         loff_t          size;
162         u64             change_attr;
163 };
164 
165 /*
166  * Generate a key to describe an NFS inode in an NFS server's index
167  */
168 static uint16_t nfs_fscache_inode_get_key(const void *cookie_netfs_data,
169                                           void *buffer, uint16_t bufmax)
170 {
171         const struct nfs_inode *nfsi = cookie_netfs_data;
172         uint16_t nsize;
173 
174         /* use the inode's NFS filehandle as the key */
175         nsize = nfsi->fh.size;
176         memcpy(buffer, nfsi->fh.data, nsize);
177         return nsize;
178 }
179 
180 /*
181  * Get certain file attributes from the netfs data
182  * - This function can be absent for an index
183  * - Not permitted to return an error
184  * - The netfs data from the cookie being used as the source is presented
185  */
186 static void nfs_fscache_inode_get_attr(const void *cookie_netfs_data,
187                                        uint64_t *size)
188 {
189         const struct nfs_inode *nfsi = cookie_netfs_data;
190 
191         *size = nfsi->vfs_inode.i_size;
192 }
193 
194 /*
195  * Get the auxiliary data from netfs data
196  * - This function can be absent if the index carries no state data
197  * - Should store the auxiliary data in the buffer
198  * - Should return the amount of amount stored
199  * - Not permitted to return an error
200  * - The netfs data from the cookie being used as the source is presented
201  */
202 static uint16_t nfs_fscache_inode_get_aux(const void *cookie_netfs_data,
203                                           void *buffer, uint16_t bufmax)
204 {
205         struct nfs_fscache_inode_auxdata auxdata;
206         const struct nfs_inode *nfsi = cookie_netfs_data;
207 
208         memset(&auxdata, 0, sizeof(auxdata));
209         auxdata.size = nfsi->vfs_inode.i_size;
210         auxdata.mtime = nfsi->vfs_inode.i_mtime;
211         auxdata.ctime = nfsi->vfs_inode.i_ctime;
212 
213         if (NFS_SERVER(&nfsi->vfs_inode)->nfs_client->rpc_ops->version == 4)
214                 auxdata.change_attr = nfsi->vfs_inode.i_version;
215 
216         if (bufmax > sizeof(auxdata))
217                 bufmax = sizeof(auxdata);
218 
219         memcpy(buffer, &auxdata, bufmax);
220         return bufmax;
221 }
222 
223 /*
224  * Consult the netfs about the state of an object
225  * - This function can be absent if the index carries no state data
226  * - The netfs data from the cookie being used as the target is
227  *   presented, as is the auxiliary data
228  */
229 static
230 enum fscache_checkaux nfs_fscache_inode_check_aux(void *cookie_netfs_data,
231                                                   const void *data,
232                                                   uint16_t datalen)
233 {
234         struct nfs_fscache_inode_auxdata auxdata;
235         struct nfs_inode *nfsi = cookie_netfs_data;
236 
237         if (datalen != sizeof(auxdata))
238                 return FSCACHE_CHECKAUX_OBSOLETE;
239 
240         memset(&auxdata, 0, sizeof(auxdata));
241         auxdata.size = nfsi->vfs_inode.i_size;
242         auxdata.mtime = nfsi->vfs_inode.i_mtime;
243         auxdata.ctime = nfsi->vfs_inode.i_ctime;
244 
245         if (NFS_SERVER(&nfsi->vfs_inode)->nfs_client->rpc_ops->version == 4)
246                 auxdata.change_attr = nfsi->vfs_inode.i_version;
247 
248         if (memcmp(data, &auxdata, datalen) != 0)
249                 return FSCACHE_CHECKAUX_OBSOLETE;
250 
251         return FSCACHE_CHECKAUX_OKAY;
252 }
253 
254 /*
255  * Indication from FS-Cache that the cookie is no longer cached
256  * - This function is called when the backing store currently caching a cookie
257  *   is removed
258  * - The netfs should use this to clean up any markers indicating cached pages
259  * - This is mandatory for any object that may have data
260  */
261 static void nfs_fscache_inode_now_uncached(void *cookie_netfs_data)
262 {
263         struct nfs_inode *nfsi = cookie_netfs_data;
264         struct pagevec pvec;
265         pgoff_t first;
266         int loop, nr_pages;
267 
268         pagevec_init(&pvec, 0);
269         first = 0;
270 
271         dprintk("NFS: nfs_inode_now_uncached: nfs_inode 0x%p\n", nfsi);
272 
273         for (;;) {
274                 /* grab a bunch of pages to unmark */
275                 nr_pages = pagevec_lookup(&pvec,
276                                           nfsi->vfs_inode.i_mapping,
277                                           first,
278                                           PAGEVEC_SIZE - pagevec_count(&pvec));
279                 if (!nr_pages)
280                         break;
281 
282                 for (loop = 0; loop < nr_pages; loop++)
283                         ClearPageFsCache(pvec.pages[loop]);
284 
285                 first = pvec.pages[nr_pages - 1]->index + 1;
286 
287                 pvec.nr = nr_pages;
288                 pagevec_release(&pvec);
289                 cond_resched();
290         }
291 }
292 
293 /*
294  * Get an extra reference on a read context.
295  * - This function can be absent if the completion function doesn't require a
296  *   context.
297  * - The read context is passed back to NFS in the event that a data read on the
298  *   cache fails with EIO - in which case the server must be contacted to
299  *   retrieve the data, which requires the read context for security.
300  */
301 static void nfs_fh_get_context(void *cookie_netfs_data, void *context)
302 {
303         get_nfs_open_context(context);
304 }
305 
306 /*
307  * Release an extra reference on a read context.
308  * - This function can be absent if the completion function doesn't require a
309  *   context.
310  */
311 static void nfs_fh_put_context(void *cookie_netfs_data, void *context)
312 {
313         if (context)
314                 put_nfs_open_context(context);
315 }
316 
317 /*
318  * Define the inode object for FS-Cache.  This is used to describe an inode
319  * object to fscache_acquire_cookie().  It is keyed by the NFS file handle for
320  * an inode.
321  *
322  * Coherency is managed by comparing the copies of i_size, i_mtime and i_ctime
323  * held in the cache auxiliary data for the data storage object with those in
324  * the inode struct in memory.
325  */
326 const struct fscache_cookie_def nfs_fscache_inode_object_def = {
327         .name           = "NFS.fh",
328         .type           = FSCACHE_COOKIE_TYPE_DATAFILE,
329         .get_key        = nfs_fscache_inode_get_key,
330         .get_attr       = nfs_fscache_inode_get_attr,
331         .get_aux        = nfs_fscache_inode_get_aux,
332         .check_aux      = nfs_fscache_inode_check_aux,
333         .now_uncached   = nfs_fscache_inode_now_uncached,
334         .get_context    = nfs_fh_get_context,
335         .put_context    = nfs_fh_put_context,
336 };
337 

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp