zte's code,first commit
Change-Id: I9a04da59e459a9bc0d67f101f700d9d7dc8d681b
diff --git a/ap/os/linux/linux-3.4.x/fs/nfs/fscache-index.c b/ap/os/linux/linux-3.4.x/fs/nfs/fscache-index.c
new file mode 100644
index 0000000..7cf2c46
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/fs/nfs/fscache-index.c
@@ -0,0 +1,337 @@
+/* NFS FS-Cache index structure definition
+ *
+ * Copyright (C) 2008 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/nfs_fs.h>
+#include <linux/nfs_fs_sb.h>
+#include <linux/in6.h>
+
+#include "internal.h"
+#include "fscache.h"
+
+#define NFSDBG_FACILITY NFSDBG_FSCACHE
+
+/*
+ * Define the NFS filesystem for FS-Cache. Upon registration FS-Cache sticks
+ * the cookie for the top-level index object for NFS into here. The top-level
+ * index can than have other cache objects inserted into it.
+ */
+struct fscache_netfs nfs_fscache_netfs = {
+ .name = "nfs",
+ .version = 0,
+};
+
+/*
+ * Register NFS for caching
+ */
+int nfs_fscache_register(void)
+{
+ return fscache_register_netfs(&nfs_fscache_netfs);
+}
+
+/*
+ * Unregister NFS for caching
+ */
+void nfs_fscache_unregister(void)
+{
+ fscache_unregister_netfs(&nfs_fscache_netfs);
+}
+
+/*
+ * Layout of the key for an NFS server cache object.
+ */
+struct nfs_server_key {
+ uint16_t nfsversion; /* NFS protocol version */
+ uint16_t family; /* address family */
+ uint16_t port; /* IP port */
+ union {
+ struct in_addr ipv4_addr; /* IPv4 address */
+ struct in6_addr ipv6_addr; /* IPv6 address */
+ } addr[0];
+};
+
+/*
+ * Generate a key to describe a server in the main NFS index
+ * - We return the length of the key, or 0 if we can't generate one
+ */
+static uint16_t nfs_server_get_key(const void *cookie_netfs_data,
+ void *buffer, uint16_t bufmax)
+{
+ const struct nfs_client *clp = cookie_netfs_data;
+ const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) &clp->cl_addr;
+ const struct sockaddr_in *sin = (struct sockaddr_in *) &clp->cl_addr;
+ struct nfs_server_key *key = buffer;
+ uint16_t len = sizeof(struct nfs_server_key);
+
+ key->nfsversion = clp->rpc_ops->version;
+ key->family = clp->cl_addr.ss_family;
+
+ memset(key, 0, len);
+
+ switch (clp->cl_addr.ss_family) {
+ case AF_INET:
+ key->port = sin->sin_port;
+ key->addr[0].ipv4_addr = sin->sin_addr;
+ len += sizeof(key->addr[0].ipv4_addr);
+ break;
+
+ case AF_INET6:
+ key->port = sin6->sin6_port;
+ key->addr[0].ipv6_addr = sin6->sin6_addr;
+ len += sizeof(key->addr[0].ipv6_addr);
+ break;
+
+ default:
+ printk(KERN_WARNING "NFS: Unknown network family '%d'\n",
+ clp->cl_addr.ss_family);
+ len = 0;
+ break;
+ }
+
+ return len;
+}
+
+/*
+ * Define the server object for FS-Cache. This is used to describe a server
+ * object to fscache_acquire_cookie(). It is keyed by the NFS protocol and
+ * server address parameters.
+ */
+const struct fscache_cookie_def nfs_fscache_server_index_def = {
+ .name = "NFS.server",
+ .type = FSCACHE_COOKIE_TYPE_INDEX,
+ .get_key = nfs_server_get_key,
+};
+
+/*
+ * Generate a key to describe a superblock key in the main NFS index
+ */
+static uint16_t nfs_super_get_key(const void *cookie_netfs_data,
+ void *buffer, uint16_t bufmax)
+{
+ const struct nfs_fscache_key *key;
+ const struct nfs_server *nfss = cookie_netfs_data;
+ uint16_t len;
+
+ key = nfss->fscache_key;
+ len = sizeof(key->key) + key->key.uniq_len;
+ if (len > bufmax) {
+ len = 0;
+ } else {
+ memcpy(buffer, &key->key, sizeof(key->key));
+ memcpy(buffer + sizeof(key->key),
+ key->key.uniquifier, key->key.uniq_len);
+ }
+
+ return len;
+}
+
+/*
+ * Define the superblock object for FS-Cache. This is used to describe a
+ * superblock object to fscache_acquire_cookie(). It is keyed by all the NFS
+ * parameters that might cause a separate superblock.
+ */
+const struct fscache_cookie_def nfs_fscache_super_index_def = {
+ .name = "NFS.super",
+ .type = FSCACHE_COOKIE_TYPE_INDEX,
+ .get_key = nfs_super_get_key,
+};
+
+/*
+ * Definition of the auxiliary data attached to NFS inode storage objects
+ * within the cache.
+ *
+ * The contents of this struct are recorded in the on-disk local cache in the
+ * auxiliary data attached to the data storage object backing an inode. This
+ * permits coherency to be managed when a new inode binds to an already extant
+ * cache object.
+ */
+struct nfs_fscache_inode_auxdata {
+ struct timespec mtime;
+ struct timespec ctime;
+ loff_t size;
+ u64 change_attr;
+};
+
+/*
+ * Generate a key to describe an NFS inode in an NFS server's index
+ */
+static uint16_t nfs_fscache_inode_get_key(const void *cookie_netfs_data,
+ void *buffer, uint16_t bufmax)
+{
+ const struct nfs_inode *nfsi = cookie_netfs_data;
+ uint16_t nsize;
+
+ /* use the inode's NFS filehandle as the key */
+ nsize = nfsi->fh.size;
+ memcpy(buffer, nfsi->fh.data, nsize);
+ return nsize;
+}
+
+/*
+ * Get certain file attributes from the netfs data
+ * - This function can be absent for an index
+ * - Not permitted to return an error
+ * - The netfs data from the cookie being used as the source is presented
+ */
+static void nfs_fscache_inode_get_attr(const void *cookie_netfs_data,
+ uint64_t *size)
+{
+ const struct nfs_inode *nfsi = cookie_netfs_data;
+
+ *size = nfsi->vfs_inode.i_size;
+}
+
+/*
+ * Get the auxiliary data from netfs data
+ * - This function can be absent if the index carries no state data
+ * - Should store the auxiliary data in the buffer
+ * - Should return the amount of amount stored
+ * - Not permitted to return an error
+ * - The netfs data from the cookie being used as the source is presented
+ */
+static uint16_t nfs_fscache_inode_get_aux(const void *cookie_netfs_data,
+ void *buffer, uint16_t bufmax)
+{
+ struct nfs_fscache_inode_auxdata auxdata;
+ const struct nfs_inode *nfsi = cookie_netfs_data;
+
+ memset(&auxdata, 0, sizeof(auxdata));
+ auxdata.size = nfsi->vfs_inode.i_size;
+ auxdata.mtime = nfsi->vfs_inode.i_mtime;
+ auxdata.ctime = nfsi->vfs_inode.i_ctime;
+
+ if (NFS_SERVER(&nfsi->vfs_inode)->nfs_client->rpc_ops->version == 4)
+ auxdata.change_attr = nfsi->vfs_inode.i_version;
+
+ if (bufmax > sizeof(auxdata))
+ bufmax = sizeof(auxdata);
+
+ memcpy(buffer, &auxdata, bufmax);
+ return bufmax;
+}
+
+/*
+ * Consult the netfs about the state of an object
+ * - This function can be absent if the index carries no state data
+ * - The netfs data from the cookie being used as the target is
+ * presented, as is the auxiliary data
+ */
+static
+enum fscache_checkaux nfs_fscache_inode_check_aux(void *cookie_netfs_data,
+ const void *data,
+ uint16_t datalen)
+{
+ struct nfs_fscache_inode_auxdata auxdata;
+ struct nfs_inode *nfsi = cookie_netfs_data;
+
+ if (datalen != sizeof(auxdata))
+ return FSCACHE_CHECKAUX_OBSOLETE;
+
+ memset(&auxdata, 0, sizeof(auxdata));
+ auxdata.size = nfsi->vfs_inode.i_size;
+ auxdata.mtime = nfsi->vfs_inode.i_mtime;
+ auxdata.ctime = nfsi->vfs_inode.i_ctime;
+
+ if (NFS_SERVER(&nfsi->vfs_inode)->nfs_client->rpc_ops->version == 4)
+ auxdata.change_attr = nfsi->vfs_inode.i_version;
+
+ if (memcmp(data, &auxdata, datalen) != 0)
+ return FSCACHE_CHECKAUX_OBSOLETE;
+
+ return FSCACHE_CHECKAUX_OKAY;
+}
+
+/*
+ * Indication from FS-Cache that the cookie is no longer cached
+ * - This function is called when the backing store currently caching a cookie
+ * is removed
+ * - The netfs should use this to clean up any markers indicating cached pages
+ * - This is mandatory for any object that may have data
+ */
+static void nfs_fscache_inode_now_uncached(void *cookie_netfs_data)
+{
+ struct nfs_inode *nfsi = cookie_netfs_data;
+ struct pagevec pvec;
+ pgoff_t first;
+ int loop, nr_pages;
+
+ pagevec_init(&pvec, 0);
+ first = 0;
+
+ dprintk("NFS: nfs_inode_now_uncached: nfs_inode 0x%p\n", nfsi);
+
+ for (;;) {
+ /* grab a bunch of pages to unmark */
+ nr_pages = pagevec_lookup(&pvec,
+ nfsi->vfs_inode.i_mapping,
+ first,
+ PAGEVEC_SIZE - pagevec_count(&pvec));
+ if (!nr_pages)
+ break;
+
+ for (loop = 0; loop < nr_pages; loop++)
+ ClearPageFsCache(pvec.pages[loop]);
+
+ first = pvec.pages[nr_pages - 1]->index + 1;
+
+ pvec.nr = nr_pages;
+ pagevec_release(&pvec);
+ cond_resched();
+ }
+}
+
+/*
+ * Get an extra reference on a read context.
+ * - This function can be absent if the completion function doesn't require a
+ * context.
+ * - The read context is passed back to NFS in the event that a data read on the
+ * cache fails with EIO - in which case the server must be contacted to
+ * retrieve the data, which requires the read context for security.
+ */
+static void nfs_fh_get_context(void *cookie_netfs_data, void *context)
+{
+ get_nfs_open_context(context);
+}
+
+/*
+ * Release an extra reference on a read context.
+ * - This function can be absent if the completion function doesn't require a
+ * context.
+ */
+static void nfs_fh_put_context(void *cookie_netfs_data, void *context)
+{
+ if (context)
+ put_nfs_open_context(context);
+}
+
+/*
+ * Define the inode object for FS-Cache. This is used to describe an inode
+ * object to fscache_acquire_cookie(). It is keyed by the NFS file handle for
+ * an inode.
+ *
+ * Coherency is managed by comparing the copies of i_size, i_mtime and i_ctime
+ * held in the cache auxiliary data for the data storage object with those in
+ * the inode struct in memory.
+ */
+const struct fscache_cookie_def nfs_fscache_inode_object_def = {
+ .name = "NFS.fh",
+ .type = FSCACHE_COOKIE_TYPE_DATAFILE,
+ .get_key = nfs_fscache_inode_get_key,
+ .get_attr = nfs_fscache_inode_get_attr,
+ .get_aux = nfs_fscache_inode_get_aux,
+ .check_aux = nfs_fscache_inode_check_aux,
+ .now_uncached = nfs_fscache_inode_now_uncached,
+ .get_context = nfs_fh_get_context,
+ .put_context = nfs_fh_put_context,
+};