[T106][ZXW-22]7520V3SCV2.01.01.02P42U09_VEC_V0.8_AP_VEC origin source commit

Change-Id: Ic6e05d89ecd62fc34f82b23dcf306c93764aec4b
diff --git a/ap/os/linux/linux-3.4.x/fs/nfs/inode.c b/ap/os/linux/linux-3.4.x/fs/nfs/inode.c
new file mode 100644
index 0000000..a6d5905
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/fs/nfs/inode.c
@@ -0,0 +1,1754 @@
+/*
+ *  linux/fs/nfs/inode.c
+ *
+ *  Copyright (C) 1992  Rick Sladkey
+ *
+ *  nfs inode and superblock handling functions
+ *
+ *  Modularised by Alan Cox <alan@lxorguk.ukuu.org.uk>, while hacking some
+ *  experimental NFS changes. Modularisation taken straight from SYS5 fs.
+ *
+ *  Change to nfs_read_super() to permit NFS mounts to multi-homed hosts.
+ *  J.S.Peatfield@damtp.cam.ac.uk
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/time.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/string.h>
+#include <linux/stat.h>
+#include <linux/errno.h>
+#include <linux/unistd.h>
+#include <linux/sunrpc/clnt.h>
+#include <linux/sunrpc/stats.h>
+#include <linux/sunrpc/metrics.h>
+#include <linux/nfs_fs.h>
+#include <linux/nfs_mount.h>
+#include <linux/nfs4_mount.h>
+#include <linux/lockd/bind.h>
+#include <linux/seq_file.h>
+#include <linux/mount.h>
+#include <linux/nfs_idmap.h>
+#include <linux/vfs.h>
+#include <linux/inet.h>
+#include <linux/nfs_xdr.h>
+#include <linux/slab.h>
+#include <linux/compat.h>
+#include <linux/freezer.h>
+#include <linux/crc32.h>
+
+#include <asm/uaccess.h>
+
+#include "nfs4_fs.h"
+#include "callback.h"
+#include "delegation.h"
+#include "iostat.h"
+#include "internal.h"
+#include "fscache.h"
+#include "dns_resolve.h"
+#include "pnfs.h"
+#include "netns.h"
+
+#define NFSDBG_FACILITY		NFSDBG_VFS
+
+#define NFS_64_BIT_INODE_NUMBERS_ENABLED	1
+
+/* Default is to see 64-bit inode numbers */
+static bool enable_ino64 = NFS_64_BIT_INODE_NUMBERS_ENABLED;
+
+static void nfs_invalidate_inode(struct inode *);
+static int nfs_update_inode(struct inode *, struct nfs_fattr *);
+
+static struct kmem_cache * nfs_inode_cachep;
+
+static inline unsigned long
+nfs_fattr_to_ino_t(struct nfs_fattr *fattr)
+{
+	return nfs_fileid_to_ino_t(fattr->fileid);
+}
+
+/**
+ * nfs_wait_bit_killable - helper for functions that are sleeping on bit locks
+ * @word: long word containing the bit lock
+ */
+int nfs_wait_bit_killable(void *word)
+{
+	if (fatal_signal_pending(current))
+		return -ERESTARTSYS;
+	freezable_schedule();
+	return 0;
+}
+
+/**
+ * nfs_compat_user_ino64 - returns the user-visible inode number
+ * @fileid: 64-bit fileid
+ *
+ * This function returns a 32-bit inode number if the boot parameter
+ * nfs.enable_ino64 is zero.
+ */
+u64 nfs_compat_user_ino64(u64 fileid)
+{
+#ifdef CONFIG_COMPAT
+	compat_ulong_t ino;
+#else	
+	unsigned long ino;
+#endif
+
+	if (enable_ino64)
+		return fileid;
+	ino = fileid;
+	if (sizeof(ino) < sizeof(fileid))
+		ino ^= fileid >> (sizeof(fileid)-sizeof(ino)) * 8;
+	return ino;
+}
+
+static void nfs_clear_inode(struct inode *inode)
+{
+	/*
+	 * The following should never happen...
+	 */
+	BUG_ON(nfs_have_writebacks(inode));
+	BUG_ON(!list_empty(&NFS_I(inode)->open_files));
+	nfs_zap_acl_cache(inode);
+	nfs_access_zap_cache(inode);
+	nfs_fscache_release_inode_cookie(inode);
+}
+
+void nfs_evict_inode(struct inode *inode)
+{
+	truncate_inode_pages(&inode->i_data, 0);
+	end_writeback(inode);
+	nfs_clear_inode(inode);
+}
+
+/**
+ * nfs_sync_mapping - helper to flush all mmapped dirty data to disk
+ */
+int nfs_sync_mapping(struct address_space *mapping)
+{
+	int ret = 0;
+
+	if (mapping->nrpages != 0) {
+		unmap_mapping_range(mapping, 0, 0, 0);
+		ret = nfs_wb_all(mapping->host);
+	}
+	return ret;
+}
+
+/*
+ * Invalidate the local caches
+ */
+static void nfs_zap_caches_locked(struct inode *inode)
+{
+	struct nfs_inode *nfsi = NFS_I(inode);
+	int mode = inode->i_mode;
+
+	nfs_inc_stats(inode, NFSIOS_ATTRINVALIDATE);
+
+	nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
+	nfsi->attrtimeo_timestamp = jiffies;
+
+	memset(NFS_I(inode)->cookieverf, 0, sizeof(NFS_I(inode)->cookieverf));
+	if (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode))
+		nfsi->cache_validity |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL|NFS_INO_REVAL_PAGECACHE;
+	else
+		nfsi->cache_validity |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL|NFS_INO_REVAL_PAGECACHE;
+}
+
+void nfs_zap_caches(struct inode *inode)
+{
+	spin_lock(&inode->i_lock);
+	nfs_zap_caches_locked(inode);
+	spin_unlock(&inode->i_lock);
+}
+
+void nfs_zap_mapping(struct inode *inode, struct address_space *mapping)
+{
+	if (mapping->nrpages != 0) {
+		spin_lock(&inode->i_lock);
+		NFS_I(inode)->cache_validity |= NFS_INO_INVALID_DATA;
+		spin_unlock(&inode->i_lock);
+	}
+}
+
+void nfs_zap_acl_cache(struct inode *inode)
+{
+	void (*clear_acl_cache)(struct inode *);
+
+	clear_acl_cache = NFS_PROTO(inode)->clear_acl_cache;
+	if (clear_acl_cache != NULL)
+		clear_acl_cache(inode);
+	spin_lock(&inode->i_lock);
+	NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_ACL;
+	spin_unlock(&inode->i_lock);
+}
+
+void nfs_invalidate_atime(struct inode *inode)
+{
+	spin_lock(&inode->i_lock);
+	NFS_I(inode)->cache_validity |= NFS_INO_INVALID_ATIME;
+	spin_unlock(&inode->i_lock);
+}
+
+/*
+ * Invalidate, but do not unhash, the inode.
+ * NB: must be called with inode->i_lock held!
+ */
+static void nfs_invalidate_inode(struct inode *inode)
+{
+	set_bit(NFS_INO_STALE, &NFS_I(inode)->flags);
+	nfs_zap_caches_locked(inode);
+}
+
+struct nfs_find_desc {
+	struct nfs_fh		*fh;
+	struct nfs_fattr	*fattr;
+};
+
+/*
+ * In NFSv3 we can have 64bit inode numbers. In order to support
+ * this, and re-exported directories (also seen in NFSv2)
+ * we are forced to allow 2 different inodes to have the same
+ * i_ino.
+ */
+static int
+nfs_find_actor(struct inode *inode, void *opaque)
+{
+	struct nfs_find_desc	*desc = (struct nfs_find_desc *)opaque;
+	struct nfs_fh		*fh = desc->fh;
+	struct nfs_fattr	*fattr = desc->fattr;
+
+	if (NFS_FILEID(inode) != fattr->fileid)
+		return 0;
+	if ((S_IFMT & inode->i_mode) != (S_IFMT & fattr->mode))
+		return 0;
+	if (nfs_compare_fh(NFS_FH(inode), fh))
+		return 0;
+	if (is_bad_inode(inode) || NFS_STALE(inode))
+		return 0;
+	return 1;
+}
+
+static int
+nfs_init_locked(struct inode *inode, void *opaque)
+{
+	struct nfs_find_desc	*desc = (struct nfs_find_desc *)opaque;
+	struct nfs_fattr	*fattr = desc->fattr;
+
+	set_nfs_fileid(inode, fattr->fileid);
+	nfs_copy_fh(NFS_FH(inode), desc->fh);
+	return 0;
+}
+
+/*
+ * This is our front-end to iget that looks up inodes by file handle
+ * instead of inode number.
+ */
+struct inode *
+nfs_fhget(struct super_block *sb, struct nfs_fh *fh, struct nfs_fattr *fattr)
+{
+	struct nfs_find_desc desc = {
+		.fh	= fh,
+		.fattr	= fattr
+	};
+	struct inode *inode = ERR_PTR(-ENOENT);
+	unsigned long hash;
+
+	nfs_attr_check_mountpoint(sb, fattr);
+
+	if (((fattr->valid & NFS_ATTR_FATTR_FILEID) == 0) &&
+	    !nfs_attr_use_mounted_on_fileid(fattr))
+		goto out_no_inode;
+	if ((fattr->valid & NFS_ATTR_FATTR_TYPE) == 0)
+		goto out_no_inode;
+
+	hash = nfs_fattr_to_ino_t(fattr);
+
+	inode = iget5_locked(sb, hash, nfs_find_actor, nfs_init_locked, &desc);
+	if (inode == NULL) {
+		inode = ERR_PTR(-ENOMEM);
+		goto out_no_inode;
+	}
+
+	if (inode->i_state & I_NEW) {
+		struct nfs_inode *nfsi = NFS_I(inode);
+		unsigned long now = jiffies;
+
+		/* We set i_ino for the few things that still rely on it,
+		 * such as stat(2) */
+		inode->i_ino = hash;
+
+		/* We can't support update_atime(), since the server will reset it */
+		inode->i_flags |= S_NOATIME|S_NOCMTIME;
+		inode->i_mode = fattr->mode;
+		if ((fattr->valid & NFS_ATTR_FATTR_MODE) == 0
+				&& nfs_server_capable(inode, NFS_CAP_MODE))
+			nfsi->cache_validity |= NFS_INO_INVALID_ATTR
+				| NFS_INO_INVALID_ACCESS
+				| NFS_INO_INVALID_ACL;
+		/* Why so? Because we want revalidate for devices/FIFOs, and
+		 * that's precisely what we have in nfs_file_inode_operations.
+		 */
+		inode->i_op = NFS_SB(sb)->nfs_client->rpc_ops->file_inode_ops;
+		if (S_ISREG(inode->i_mode)) {
+			inode->i_fop = NFS_SB(sb)->nfs_client->rpc_ops->file_ops;
+			inode->i_data.a_ops = &nfs_file_aops;
+			inode->i_data.backing_dev_info = &NFS_SB(sb)->backing_dev_info;
+		} else if (S_ISDIR(inode->i_mode)) {
+			inode->i_op = NFS_SB(sb)->nfs_client->rpc_ops->dir_inode_ops;
+			inode->i_fop = &nfs_dir_operations;
+			inode->i_data.a_ops = &nfs_dir_aops;
+			if (nfs_server_capable(inode, NFS_CAP_READDIRPLUS))
+				set_bit(NFS_INO_ADVISE_RDPLUS, &NFS_I(inode)->flags);
+			/* Deal with crossing mountpoints */
+			if (fattr->valid & NFS_ATTR_FATTR_MOUNTPOINT ||
+					fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL) {
+				if (fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL)
+					inode->i_op = &nfs_referral_inode_operations;
+				else
+					inode->i_op = &nfs_mountpoint_inode_operations;
+				inode->i_fop = NULL;
+				inode->i_flags |= S_AUTOMOUNT;
+			}
+		} else if (S_ISLNK(inode->i_mode))
+			inode->i_op = &nfs_symlink_inode_operations;
+		else
+			init_special_inode(inode, inode->i_mode, fattr->rdev);
+
+		memset(&inode->i_atime, 0, sizeof(inode->i_atime));
+		memset(&inode->i_mtime, 0, sizeof(inode->i_mtime));
+		memset(&inode->i_ctime, 0, sizeof(inode->i_ctime));
+		inode->i_version = 0;
+		inode->i_size = 0;
+		clear_nlink(inode);
+		inode->i_uid = -2;
+		inode->i_gid = -2;
+		inode->i_blocks = 0;
+		memset(nfsi->cookieverf, 0, sizeof(nfsi->cookieverf));
+
+		nfsi->read_cache_jiffies = fattr->time_start;
+		nfsi->attr_gencount = fattr->gencount;
+		if (fattr->valid & NFS_ATTR_FATTR_ATIME)
+			inode->i_atime = fattr->atime;
+		else if (nfs_server_capable(inode, NFS_CAP_ATIME))
+			nfsi->cache_validity |= NFS_INO_INVALID_ATTR;
+		if (fattr->valid & NFS_ATTR_FATTR_MTIME)
+			inode->i_mtime = fattr->mtime;
+		else if (nfs_server_capable(inode, NFS_CAP_MTIME))
+			nfsi->cache_validity |= NFS_INO_INVALID_ATTR
+				| NFS_INO_INVALID_DATA;
+		if (fattr->valid & NFS_ATTR_FATTR_CTIME)
+			inode->i_ctime = fattr->ctime;
+		else if (nfs_server_capable(inode, NFS_CAP_CTIME))
+			nfsi->cache_validity |= NFS_INO_INVALID_ATTR
+				| NFS_INO_INVALID_ACCESS
+				| NFS_INO_INVALID_ACL;
+		if (fattr->valid & NFS_ATTR_FATTR_CHANGE)
+			inode->i_version = fattr->change_attr;
+		else if (nfs_server_capable(inode, NFS_CAP_CHANGE_ATTR))
+			nfsi->cache_validity |= NFS_INO_INVALID_ATTR
+				| NFS_INO_INVALID_DATA;
+		if (fattr->valid & NFS_ATTR_FATTR_SIZE)
+			inode->i_size = nfs_size_to_loff_t(fattr->size);
+		else
+			nfsi->cache_validity |= NFS_INO_INVALID_ATTR
+				| NFS_INO_INVALID_DATA
+				| NFS_INO_REVAL_PAGECACHE;
+		if (fattr->valid & NFS_ATTR_FATTR_NLINK)
+			set_nlink(inode, fattr->nlink);
+		else if (nfs_server_capable(inode, NFS_CAP_NLINK))
+			nfsi->cache_validity |= NFS_INO_INVALID_ATTR;
+		if (fattr->valid & NFS_ATTR_FATTR_OWNER)
+			inode->i_uid = fattr->uid;
+		else if (nfs_server_capable(inode, NFS_CAP_OWNER))
+			nfsi->cache_validity |= NFS_INO_INVALID_ATTR
+				| NFS_INO_INVALID_ACCESS
+				| NFS_INO_INVALID_ACL;
+		if (fattr->valid & NFS_ATTR_FATTR_GROUP)
+			inode->i_gid = fattr->gid;
+		else if (nfs_server_capable(inode, NFS_CAP_OWNER_GROUP))
+			nfsi->cache_validity |= NFS_INO_INVALID_ATTR
+				| NFS_INO_INVALID_ACCESS
+				| NFS_INO_INVALID_ACL;
+		if (fattr->valid & NFS_ATTR_FATTR_BLOCKS_USED)
+			inode->i_blocks = fattr->du.nfs2.blocks;
+		if (fattr->valid & NFS_ATTR_FATTR_SPACE_USED) {
+			/*
+			 * report the blocks in 512byte units
+			 */
+			inode->i_blocks = nfs_calc_block_size(fattr->du.nfs3.used);
+		}
+		nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
+		nfsi->attrtimeo_timestamp = now;
+		nfsi->access_cache = RB_ROOT;
+
+		nfs_fscache_init_inode_cookie(inode);
+
+		unlock_new_inode(inode);
+	} else
+		nfs_refresh_inode(inode, fattr);
+	dprintk("NFS: nfs_fhget(%s/%Ld fh_crc=0x%08x ct=%d)\n",
+		inode->i_sb->s_id,
+		(long long)NFS_FILEID(inode),
+		nfs_display_fhandle_hash(fh),
+		atomic_read(&inode->i_count));
+
+out:
+	return inode;
+
+out_no_inode:
+	dprintk("nfs_fhget: iget failed with error %ld\n", PTR_ERR(inode));
+	goto out;
+}
+
+#define NFS_VALID_ATTRS (ATTR_MODE|ATTR_UID|ATTR_GID|ATTR_SIZE|ATTR_ATIME|ATTR_ATIME_SET|ATTR_MTIME|ATTR_MTIME_SET|ATTR_FILE|ATTR_OPEN)
+
+int
+nfs_setattr(struct dentry *dentry, struct iattr *attr)
+{
+	struct inode *inode = dentry->d_inode;
+	struct nfs_fattr *fattr;
+	int error = -ENOMEM;
+
+	nfs_inc_stats(inode, NFSIOS_VFSSETATTR);
+
+	/* skip mode change if it's just for clearing setuid/setgid */
+	if (attr->ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID))
+		attr->ia_valid &= ~ATTR_MODE;
+
+	if (attr->ia_valid & ATTR_SIZE) {
+		if (!S_ISREG(inode->i_mode) || attr->ia_size == i_size_read(inode))
+			attr->ia_valid &= ~ATTR_SIZE;
+	}
+
+	/* Optimization: if the end result is no change, don't RPC */
+	attr->ia_valid &= NFS_VALID_ATTRS;
+	if ((attr->ia_valid & ~(ATTR_FILE|ATTR_OPEN)) == 0)
+		return 0;
+
+	/* Write all dirty data */
+	if (S_ISREG(inode->i_mode))
+		nfs_wb_all(inode);
+
+	fattr = nfs_alloc_fattr();
+	if (fattr == NULL)
+		goto out;
+	/*
+	 * Return any delegations if we're going to change ACLs
+	 */
+	if ((attr->ia_valid & (ATTR_MODE|ATTR_UID|ATTR_GID)) != 0)
+		nfs_inode_return_delegation(inode);
+	error = NFS_PROTO(inode)->setattr(dentry, fattr, attr);
+	if (error == 0)
+		nfs_refresh_inode(inode, fattr);
+	nfs_free_fattr(fattr);
+out:
+	return error;
+}
+
+/**
+ * nfs_vmtruncate - unmap mappings "freed" by truncate() syscall
+ * @inode: inode of the file used
+ * @offset: file offset to start truncating
+ *
+ * This is a copy of the common vmtruncate, but with the locking
+ * corrected to take into account the fact that NFS requires
+ * inode->i_size to be updated under the inode->i_lock.
+ */
+static int nfs_vmtruncate(struct inode * inode, loff_t offset)
+{
+	loff_t oldsize;
+	int err;
+
+	err = inode_newsize_ok(inode, offset);
+	if (err)
+		goto out;
+
+	spin_lock(&inode->i_lock);
+	oldsize = inode->i_size;
+	i_size_write(inode, offset);
+	spin_unlock(&inode->i_lock);
+
+	truncate_pagecache(inode, oldsize, offset);
+out:
+	return err;
+}
+
+/**
+ * nfs_setattr_update_inode - Update inode metadata after a setattr call.
+ * @inode: pointer to struct inode
+ * @attr: pointer to struct iattr
+ *
+ * Note: we do this in the *proc.c in order to ensure that
+ *       it works for things like exclusive creates too.
+ */
+void nfs_setattr_update_inode(struct inode *inode, struct iattr *attr)
+{
+	if ((attr->ia_valid & (ATTR_MODE|ATTR_UID|ATTR_GID)) != 0) {
+		spin_lock(&inode->i_lock);
+		if ((attr->ia_valid & ATTR_MODE) != 0) {
+			int mode = attr->ia_mode & S_IALLUGO;
+			mode |= inode->i_mode & ~S_IALLUGO;
+			inode->i_mode = mode;
+		}
+		if ((attr->ia_valid & ATTR_UID) != 0)
+			inode->i_uid = attr->ia_uid;
+		if ((attr->ia_valid & ATTR_GID) != 0)
+			inode->i_gid = attr->ia_gid;
+		NFS_I(inode)->cache_validity |= NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
+		spin_unlock(&inode->i_lock);
+	}
+	if ((attr->ia_valid & ATTR_SIZE) != 0) {
+		nfs_inc_stats(inode, NFSIOS_SETATTRTRUNC);
+		nfs_vmtruncate(inode, attr->ia_size);
+	}
+}
+
+int nfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
+{
+	struct inode *inode = dentry->d_inode;
+	int need_atime = NFS_I(inode)->cache_validity & NFS_INO_INVALID_ATIME;
+	int err = 0;
+
+	/* Flush out writes to the server in order to update c/mtime.  */
+	if (S_ISREG(inode->i_mode)) {
+		err = filemap_write_and_wait(inode->i_mapping);
+		if (err)
+			goto out;
+	}
+
+	/*
+	 * We may force a getattr if the user cares about atime.
+	 *
+	 * Note that we only have to check the vfsmount flags here:
+	 *  - NFS always sets S_NOATIME by so checking it would give a
+	 *    bogus result
+	 *  - NFS never sets MS_NOATIME or MS_NODIRATIME so there is
+	 *    no point in checking those.
+	 */
+ 	if ((mnt->mnt_flags & MNT_NOATIME) ||
+ 	    ((mnt->mnt_flags & MNT_NODIRATIME) && S_ISDIR(inode->i_mode)))
+		need_atime = 0;
+
+	if (need_atime)
+		err = __nfs_revalidate_inode(NFS_SERVER(inode), inode);
+	else
+		err = nfs_revalidate_inode(NFS_SERVER(inode), inode);
+	if (!err) {
+		generic_fillattr(inode, stat);
+		stat->ino = nfs_compat_user_ino64(NFS_FILEID(inode));
+	}
+out:
+	return err;
+}
+
+static void nfs_init_lock_context(struct nfs_lock_context *l_ctx)
+{
+	atomic_set(&l_ctx->count, 1);
+	l_ctx->lockowner = current->files;
+	l_ctx->pid = current->tgid;
+	INIT_LIST_HEAD(&l_ctx->list);
+}
+
+static struct nfs_lock_context *__nfs_find_lock_context(struct nfs_open_context *ctx)
+{
+	struct nfs_lock_context *pos;
+
+	list_for_each_entry(pos, &ctx->lock_context.list, list) {
+		if (pos->lockowner != current->files)
+			continue;
+		if (pos->pid != current->tgid)
+			continue;
+		atomic_inc(&pos->count);
+		return pos;
+	}
+	return NULL;
+}
+
+struct nfs_lock_context *nfs_get_lock_context(struct nfs_open_context *ctx)
+{
+	struct nfs_lock_context *res, *new = NULL;
+	struct inode *inode = ctx->dentry->d_inode;
+
+	spin_lock(&inode->i_lock);
+	res = __nfs_find_lock_context(ctx);
+	if (res == NULL) {
+		spin_unlock(&inode->i_lock);
+		new = kmalloc(sizeof(*new), GFP_KERNEL);
+		if (new == NULL)
+			return NULL;
+		nfs_init_lock_context(new);
+		spin_lock(&inode->i_lock);
+		res = __nfs_find_lock_context(ctx);
+		if (res == NULL) {
+			list_add_tail(&new->list, &ctx->lock_context.list);
+			new->open_context = ctx;
+			res = new;
+			new = NULL;
+		}
+	}
+	spin_unlock(&inode->i_lock);
+	kfree(new);
+	return res;
+}
+
+void nfs_put_lock_context(struct nfs_lock_context *l_ctx)
+{
+	struct nfs_open_context *ctx = l_ctx->open_context;
+	struct inode *inode = ctx->dentry->d_inode;
+
+	if (!atomic_dec_and_lock(&l_ctx->count, &inode->i_lock))
+		return;
+	list_del(&l_ctx->list);
+	spin_unlock(&inode->i_lock);
+	kfree(l_ctx);
+}
+
+/**
+ * nfs_close_context - Common close_context() routine NFSv2/v3
+ * @ctx: pointer to context
+ * @is_sync: is this a synchronous close
+ *
+ * always ensure that the attributes are up to date if we're mounted
+ * with close-to-open semantics
+ */
+void nfs_close_context(struct nfs_open_context *ctx, int is_sync)
+{
+	struct inode *inode;
+	struct nfs_server *server;
+
+	if (!(ctx->mode & FMODE_WRITE))
+		return;
+	if (!is_sync)
+		return;
+	inode = ctx->dentry->d_inode;
+	if (!list_empty(&NFS_I(inode)->open_files))
+		return;
+	server = NFS_SERVER(inode);
+	if (server->flags & NFS_MOUNT_NOCTO)
+		return;
+	nfs_revalidate_inode(server, inode);
+}
+
+struct nfs_open_context *alloc_nfs_open_context(struct dentry *dentry, fmode_t f_mode)
+{
+	struct nfs_open_context *ctx;
+	struct rpc_cred *cred = rpc_lookup_cred();
+	if (IS_ERR(cred))
+		return ERR_CAST(cred);
+
+	ctx = kmalloc(sizeof(*ctx), GFP_KERNEL);
+	if (!ctx) {
+		put_rpccred(cred);
+		return ERR_PTR(-ENOMEM);
+	}
+	nfs_sb_active(dentry->d_sb);
+	ctx->dentry = dget(dentry);
+	ctx->cred = cred;
+	ctx->state = NULL;
+	ctx->mode = f_mode;
+	ctx->flags = 0;
+	ctx->error = 0;
+	nfs_init_lock_context(&ctx->lock_context);
+	ctx->lock_context.open_context = ctx;
+	INIT_LIST_HEAD(&ctx->list);
+	return ctx;
+}
+
+struct nfs_open_context *get_nfs_open_context(struct nfs_open_context *ctx)
+{
+	if (ctx != NULL)
+		atomic_inc(&ctx->lock_context.count);
+	return ctx;
+}
+
+static void __put_nfs_open_context(struct nfs_open_context *ctx, int is_sync)
+{
+	struct inode *inode = ctx->dentry->d_inode;
+	struct super_block *sb = ctx->dentry->d_sb;
+
+	if (!list_empty(&ctx->list)) {
+		if (!atomic_dec_and_lock(&ctx->lock_context.count, &inode->i_lock))
+			return;
+		list_del(&ctx->list);
+		spin_unlock(&inode->i_lock);
+	} else if (!atomic_dec_and_test(&ctx->lock_context.count))
+		return;
+	if (inode != NULL)
+		NFS_PROTO(inode)->close_context(ctx, is_sync);
+	if (ctx->cred != NULL)
+		put_rpccred(ctx->cred);
+	dput(ctx->dentry);
+	nfs_sb_deactive(sb);
+	kfree(ctx);
+}
+
+void put_nfs_open_context(struct nfs_open_context *ctx)
+{
+	__put_nfs_open_context(ctx, 0);
+}
+
+/*
+ * Ensure that mmap has a recent RPC credential for use when writing out
+ * shared pages
+ */
+void nfs_file_set_open_context(struct file *filp, struct nfs_open_context *ctx)
+{
+	struct inode *inode = filp->f_path.dentry->d_inode;
+	struct nfs_inode *nfsi = NFS_I(inode);
+
+	filp->private_data = get_nfs_open_context(ctx);
+	spin_lock(&inode->i_lock);
+	list_add(&ctx->list, &nfsi->open_files);
+	spin_unlock(&inode->i_lock);
+}
+
+/*
+ * Given an inode, search for an open context with the desired characteristics
+ */
+struct nfs_open_context *nfs_find_open_context(struct inode *inode, struct rpc_cred *cred, fmode_t mode)
+{
+	struct nfs_inode *nfsi = NFS_I(inode);
+	struct nfs_open_context *pos, *ctx = NULL;
+
+	spin_lock(&inode->i_lock);
+	list_for_each_entry(pos, &nfsi->open_files, list) {
+		if (cred != NULL && pos->cred != cred)
+			continue;
+		if ((pos->mode & (FMODE_READ|FMODE_WRITE)) != mode)
+			continue;
+		ctx = get_nfs_open_context(pos);
+		break;
+	}
+	spin_unlock(&inode->i_lock);
+	return ctx;
+}
+
+static void nfs_file_clear_open_context(struct file *filp)
+{
+	struct inode *inode = filp->f_path.dentry->d_inode;
+	struct nfs_open_context *ctx = nfs_file_open_context(filp);
+
+	if (ctx) {
+		filp->private_data = NULL;
+		spin_lock(&inode->i_lock);
+		list_move_tail(&ctx->list, &NFS_I(inode)->open_files);
+		spin_unlock(&inode->i_lock);
+		__put_nfs_open_context(ctx, filp->f_flags & O_DIRECT ? 0 : 1);
+	}
+}
+
+/*
+ * These allocate and release file read/write context information.
+ */
+int nfs_open(struct inode *inode, struct file *filp)
+{
+	struct nfs_open_context *ctx;
+
+	ctx = alloc_nfs_open_context(filp->f_path.dentry, filp->f_mode);
+	if (IS_ERR(ctx))
+		return PTR_ERR(ctx);
+	nfs_file_set_open_context(filp, ctx);
+	put_nfs_open_context(ctx);
+	nfs_fscache_set_inode_cookie(inode, filp);
+	return 0;
+}
+
+int nfs_release(struct inode *inode, struct file *filp)
+{
+	nfs_file_clear_open_context(filp);
+	return 0;
+}
+
+/*
+ * This function is called whenever some part of NFS notices that
+ * the cached attributes have to be refreshed.
+ */
+int
+__nfs_revalidate_inode(struct nfs_server *server, struct inode *inode)
+{
+	int		 status = -ESTALE;
+	struct nfs_fattr *fattr = NULL;
+	struct nfs_inode *nfsi = NFS_I(inode);
+
+	dfprintk(PAGECACHE, "NFS: revalidating (%s/%Ld)\n",
+		inode->i_sb->s_id, (long long)NFS_FILEID(inode));
+
+	if (is_bad_inode(inode))
+		goto out;
+	if (NFS_STALE(inode))
+		goto out;
+
+	status = -ENOMEM;
+	fattr = nfs_alloc_fattr();
+	if (fattr == NULL)
+		goto out;
+
+	nfs_inc_stats(inode, NFSIOS_INODEREVALIDATE);
+	status = NFS_PROTO(inode)->getattr(server, NFS_FH(inode), fattr);
+	if (status != 0) {
+		dfprintk(PAGECACHE, "nfs_revalidate_inode: (%s/%Ld) getattr failed, error=%d\n",
+			 inode->i_sb->s_id,
+			 (long long)NFS_FILEID(inode), status);
+		if (status == -ESTALE) {
+			nfs_zap_caches(inode);
+			if (!S_ISDIR(inode->i_mode))
+				set_bit(NFS_INO_STALE, &NFS_I(inode)->flags);
+		}
+		goto out;
+	}
+
+	status = nfs_refresh_inode(inode, fattr);
+	if (status) {
+		dfprintk(PAGECACHE, "nfs_revalidate_inode: (%s/%Ld) refresh failed, error=%d\n",
+			 inode->i_sb->s_id,
+			 (long long)NFS_FILEID(inode), status);
+		goto out;
+	}
+
+	if (nfsi->cache_validity & NFS_INO_INVALID_ACL)
+		nfs_zap_acl_cache(inode);
+
+	dfprintk(PAGECACHE, "NFS: (%s/%Ld) revalidation complete\n",
+		inode->i_sb->s_id,
+		(long long)NFS_FILEID(inode));
+
+ out:
+	nfs_free_fattr(fattr);
+	return status;
+}
+
+int nfs_attribute_timeout(struct inode *inode)
+{
+	struct nfs_inode *nfsi = NFS_I(inode);
+
+	return !time_in_range_open(jiffies, nfsi->read_cache_jiffies, nfsi->read_cache_jiffies + nfsi->attrtimeo);
+}
+
+static int nfs_attribute_cache_expired(struct inode *inode)
+{
+	if (nfs_have_delegated_attributes(inode))
+		return 0;
+	return nfs_attribute_timeout(inode);
+}
+
+/**
+ * nfs_revalidate_inode - Revalidate the inode attributes
+ * @server - pointer to nfs_server struct
+ * @inode - pointer to inode struct
+ *
+ * Updates inode attribute information by retrieving the data from the server.
+ */
+int nfs_revalidate_inode(struct nfs_server *server, struct inode *inode)
+{
+	if (!(NFS_I(inode)->cache_validity & NFS_INO_INVALID_ATTR)
+			&& !nfs_attribute_cache_expired(inode))
+		return NFS_STALE(inode) ? -ESTALE : 0;
+	return __nfs_revalidate_inode(server, inode);
+}
+
+static int nfs_invalidate_mapping(struct inode *inode, struct address_space *mapping)
+{
+	struct nfs_inode *nfsi = NFS_I(inode);
+	
+	if (mapping->nrpages != 0) {
+		int ret = invalidate_inode_pages2(mapping);
+		if (ret < 0)
+			return ret;
+	}
+	spin_lock(&inode->i_lock);
+	nfsi->cache_validity &= ~NFS_INO_INVALID_DATA;
+	if (S_ISDIR(inode->i_mode))
+		memset(nfsi->cookieverf, 0, sizeof(nfsi->cookieverf));
+	spin_unlock(&inode->i_lock);
+	nfs_inc_stats(inode, NFSIOS_DATAINVALIDATE);
+	nfs_fscache_reset_inode_cookie(inode);
+	dfprintk(PAGECACHE, "NFS: (%s/%Ld) data cache invalidated\n",
+			inode->i_sb->s_id, (long long)NFS_FILEID(inode));
+	return 0;
+}
+
+/**
+ * nfs_revalidate_mapping - Revalidate the pagecache
+ * @inode - pointer to host inode
+ * @mapping - pointer to mapping
+ */
+int nfs_revalidate_mapping(struct inode *inode, struct address_space *mapping)
+{
+	struct nfs_inode *nfsi = NFS_I(inode);
+	int ret = 0;
+
+	if ((nfsi->cache_validity & NFS_INO_REVAL_PAGECACHE)
+			|| nfs_attribute_cache_expired(inode)
+			|| NFS_STALE(inode)) {
+		ret = __nfs_revalidate_inode(NFS_SERVER(inode), inode);
+		if (ret < 0)
+			goto out;
+	}
+	if (nfsi->cache_validity & NFS_INO_INVALID_DATA)
+		ret = nfs_invalidate_mapping(inode, mapping);
+out:
+	return ret;
+}
+
+static unsigned long nfs_wcc_update_inode(struct inode *inode, struct nfs_fattr *fattr)
+{
+	struct nfs_inode *nfsi = NFS_I(inode);
+	unsigned long ret = 0;
+
+	if ((fattr->valid & NFS_ATTR_FATTR_PRECHANGE)
+			&& (fattr->valid & NFS_ATTR_FATTR_CHANGE)
+			&& inode->i_version == fattr->pre_change_attr) {
+		inode->i_version = fattr->change_attr;
+		if (S_ISDIR(inode->i_mode))
+			nfsi->cache_validity |= NFS_INO_INVALID_DATA;
+		ret |= NFS_INO_INVALID_ATTR;
+	}
+	/* If we have atomic WCC data, we may update some attributes */
+	if ((fattr->valid & NFS_ATTR_FATTR_PRECTIME)
+			&& (fattr->valid & NFS_ATTR_FATTR_CTIME)
+			&& timespec_equal(&inode->i_ctime, &fattr->pre_ctime)) {
+		memcpy(&inode->i_ctime, &fattr->ctime, sizeof(inode->i_ctime));
+		ret |= NFS_INO_INVALID_ATTR;
+	}
+
+	if ((fattr->valid & NFS_ATTR_FATTR_PREMTIME)
+			&& (fattr->valid & NFS_ATTR_FATTR_MTIME)
+			&& timespec_equal(&inode->i_mtime, &fattr->pre_mtime)) {
+		memcpy(&inode->i_mtime, &fattr->mtime, sizeof(inode->i_mtime));
+		if (S_ISDIR(inode->i_mode))
+			nfsi->cache_validity |= NFS_INO_INVALID_DATA;
+		ret |= NFS_INO_INVALID_ATTR;
+	}
+	if ((fattr->valid & NFS_ATTR_FATTR_PRESIZE)
+			&& (fattr->valid & NFS_ATTR_FATTR_SIZE)
+			&& i_size_read(inode) == nfs_size_to_loff_t(fattr->pre_size)
+			&& nfsi->npages == 0) {
+		i_size_write(inode, nfs_size_to_loff_t(fattr->size));
+		ret |= NFS_INO_INVALID_ATTR;
+	}
+	return ret;
+}
+
+/**
+ * nfs_check_inode_attributes - verify consistency of the inode attribute cache
+ * @inode - pointer to inode
+ * @fattr - updated attributes
+ *
+ * Verifies the attribute cache. If we have just changed the attributes,
+ * so that fattr carries weak cache consistency data, then it may
+ * also update the ctime/mtime/change_attribute.
+ */
+static int nfs_check_inode_attributes(struct inode *inode, struct nfs_fattr *fattr)
+{
+	struct nfs_inode *nfsi = NFS_I(inode);
+	loff_t cur_size, new_isize;
+	unsigned long invalid = 0;
+
+
+	/* Has the inode gone and changed behind our back? */
+	if ((fattr->valid & NFS_ATTR_FATTR_FILEID) && nfsi->fileid != fattr->fileid)
+		return -EIO;
+	if ((fattr->valid & NFS_ATTR_FATTR_TYPE) && (inode->i_mode & S_IFMT) != (fattr->mode & S_IFMT))
+		return -EIO;
+
+	if ((fattr->valid & NFS_ATTR_FATTR_CHANGE) != 0 &&
+			inode->i_version != fattr->change_attr)
+		invalid |= NFS_INO_INVALID_ATTR|NFS_INO_REVAL_PAGECACHE;
+
+	/* Verify a few of the more important attributes */
+	if ((fattr->valid & NFS_ATTR_FATTR_MTIME) && !timespec_equal(&inode->i_mtime, &fattr->mtime))
+		invalid |= NFS_INO_INVALID_ATTR|NFS_INO_REVAL_PAGECACHE;
+
+	if (fattr->valid & NFS_ATTR_FATTR_SIZE) {
+		cur_size = i_size_read(inode);
+		new_isize = nfs_size_to_loff_t(fattr->size);
+		if (cur_size != new_isize && nfsi->npages == 0)
+			invalid |= NFS_INO_INVALID_ATTR|NFS_INO_REVAL_PAGECACHE;
+	}
+
+	/* Have any file permissions changed? */
+	if ((fattr->valid & NFS_ATTR_FATTR_MODE) && (inode->i_mode & S_IALLUGO) != (fattr->mode & S_IALLUGO))
+		invalid |= NFS_INO_INVALID_ATTR | NFS_INO_INVALID_ACCESS | NFS_INO_INVALID_ACL;
+	if ((fattr->valid & NFS_ATTR_FATTR_OWNER) && inode->i_uid != fattr->uid)
+		invalid |= NFS_INO_INVALID_ATTR | NFS_INO_INVALID_ACCESS | NFS_INO_INVALID_ACL;
+	if ((fattr->valid & NFS_ATTR_FATTR_GROUP) && inode->i_gid != fattr->gid)
+		invalid |= NFS_INO_INVALID_ATTR | NFS_INO_INVALID_ACCESS | NFS_INO_INVALID_ACL;
+
+	/* Has the link count changed? */
+	if ((fattr->valid & NFS_ATTR_FATTR_NLINK) && inode->i_nlink != fattr->nlink)
+		invalid |= NFS_INO_INVALID_ATTR;
+
+	if ((fattr->valid & NFS_ATTR_FATTR_ATIME) && !timespec_equal(&inode->i_atime, &fattr->atime))
+		invalid |= NFS_INO_INVALID_ATIME;
+
+	if (invalid != 0)
+		nfsi->cache_validity |= invalid;
+
+	nfsi->read_cache_jiffies = fattr->time_start;
+	return 0;
+}
+
+static int nfs_ctime_need_update(const struct inode *inode, const struct nfs_fattr *fattr)
+{
+	if (!(fattr->valid & NFS_ATTR_FATTR_CTIME))
+		return 0;
+	return timespec_compare(&fattr->ctime, &inode->i_ctime) > 0;
+}
+
+static int nfs_size_need_update(const struct inode *inode, const struct nfs_fattr *fattr)
+{
+	if (!(fattr->valid & NFS_ATTR_FATTR_SIZE))
+		return 0;
+	return nfs_size_to_loff_t(fattr->size) > i_size_read(inode);
+}
+
+static atomic_long_t nfs_attr_generation_counter;
+
+static unsigned long nfs_read_attr_generation_counter(void)
+{
+	return atomic_long_read(&nfs_attr_generation_counter);
+}
+
+unsigned long nfs_inc_attr_generation_counter(void)
+{
+	return atomic_long_inc_return(&nfs_attr_generation_counter);
+}
+
+void nfs_fattr_init(struct nfs_fattr *fattr)
+{
+	fattr->valid = 0;
+	fattr->time_start = jiffies;
+	fattr->gencount = nfs_inc_attr_generation_counter();
+	fattr->owner_name = NULL;
+	fattr->group_name = NULL;
+}
+
+struct nfs_fattr *nfs_alloc_fattr(void)
+{
+	struct nfs_fattr *fattr;
+
+	fattr = kmalloc(sizeof(*fattr), GFP_NOFS);
+	if (fattr != NULL)
+		nfs_fattr_init(fattr);
+	return fattr;
+}
+
+struct nfs_fh *nfs_alloc_fhandle(void)
+{
+	struct nfs_fh *fh;
+
+	fh = kmalloc(sizeof(struct nfs_fh), GFP_NOFS);
+	if (fh != NULL)
+		fh->size = 0;
+	return fh;
+}
+
+#ifdef NFS_DEBUG
+/*
+ * _nfs_display_fhandle_hash - calculate the crc32 hash for the filehandle
+ *                             in the same way that wireshark does
+ *
+ * @fh: file handle
+ *
+ * For debugging only.
+ */
+u32 _nfs_display_fhandle_hash(const struct nfs_fh *fh)
+{
+	/* wireshark uses 32-bit AUTODIN crc and does a bitwise
+	 * not on the result */
+	return ~crc32(0xFFFFFFFF, &fh->data[0], fh->size);
+}
+
+/*
+ * _nfs_display_fhandle - display an NFS file handle on the console
+ *
+ * @fh: file handle to display
+ * @caption: display caption
+ *
+ * For debugging only.
+ */
+void _nfs_display_fhandle(const struct nfs_fh *fh, const char *caption)
+{
+	unsigned short i;
+
+	if (fh == NULL || fh->size == 0) {
+		printk(KERN_DEFAULT "%s at %p is empty\n", caption, fh);
+		return;
+	}
+
+	printk(KERN_DEFAULT "%s at %p is %u bytes, crc: 0x%08x:\n",
+	       caption, fh, fh->size, _nfs_display_fhandle_hash(fh));
+	for (i = 0; i < fh->size; i += 16) {
+		__be32 *pos = (__be32 *)&fh->data[i];
+
+		switch ((fh->size - i - 1) >> 2) {
+		case 0:
+			printk(KERN_DEFAULT " %08x\n",
+				be32_to_cpup(pos));
+			break;
+		case 1:
+			printk(KERN_DEFAULT " %08x %08x\n",
+				be32_to_cpup(pos), be32_to_cpup(pos + 1));
+			break;
+		case 2:
+			printk(KERN_DEFAULT " %08x %08x %08x\n",
+				be32_to_cpup(pos), be32_to_cpup(pos + 1),
+				be32_to_cpup(pos + 2));
+			break;
+		default:
+			printk(KERN_DEFAULT " %08x %08x %08x %08x\n",
+				be32_to_cpup(pos), be32_to_cpup(pos + 1),
+				be32_to_cpup(pos + 2), be32_to_cpup(pos + 3));
+		}
+	}
+}
+#endif
+
+/**
+ * nfs_inode_attrs_need_update - check if the inode attributes need updating
+ * @inode - pointer to inode
+ * @fattr - attributes
+ *
+ * Attempt to divine whether or not an RPC call reply carrying stale
+ * attributes got scheduled after another call carrying updated ones.
+ *
+ * To do so, the function first assumes that a more recent ctime means
+ * that the attributes in fattr are newer, however it also attempt to
+ * catch the case where ctime either didn't change, or went backwards
+ * (if someone reset the clock on the server) by looking at whether
+ * or not this RPC call was started after the inode was last updated.
+ * Note also the check for wraparound of 'attr_gencount'
+ *
+ * The function returns 'true' if it thinks the attributes in 'fattr' are
+ * more recent than the ones cached in the inode.
+ *
+ */
+static int nfs_inode_attrs_need_update(const struct inode *inode, const struct nfs_fattr *fattr)
+{
+	const struct nfs_inode *nfsi = NFS_I(inode);
+
+	return ((long)fattr->gencount - (long)nfsi->attr_gencount) > 0 ||
+		nfs_ctime_need_update(inode, fattr) ||
+		nfs_size_need_update(inode, fattr) ||
+		((long)nfsi->attr_gencount - (long)nfs_read_attr_generation_counter() > 0);
+}
+
+static int nfs_refresh_inode_locked(struct inode *inode, struct nfs_fattr *fattr)
+{
+	if (nfs_inode_attrs_need_update(inode, fattr))
+		return nfs_update_inode(inode, fattr);
+	return nfs_check_inode_attributes(inode, fattr);
+}
+
+/**
+ * nfs_refresh_inode - try to update the inode attribute cache
+ * @inode - pointer to inode
+ * @fattr - updated attributes
+ *
+ * Check that an RPC call that returned attributes has not overlapped with
+ * other recent updates of the inode metadata, then decide whether it is
+ * safe to do a full update of the inode attributes, or whether just to
+ * call nfs_check_inode_attributes.
+ */
+int nfs_refresh_inode(struct inode *inode, struct nfs_fattr *fattr)
+{
+	int status;
+
+	if ((fattr->valid & NFS_ATTR_FATTR) == 0)
+		return 0;
+	spin_lock(&inode->i_lock);
+	status = nfs_refresh_inode_locked(inode, fattr);
+	spin_unlock(&inode->i_lock);
+
+	return status;
+}
+
+static int nfs_post_op_update_inode_locked(struct inode *inode, struct nfs_fattr *fattr)
+{
+	struct nfs_inode *nfsi = NFS_I(inode);
+
+	nfsi->cache_validity |= NFS_INO_INVALID_ATTR|NFS_INO_REVAL_PAGECACHE;
+	if (S_ISDIR(inode->i_mode))
+		nfsi->cache_validity |= NFS_INO_INVALID_DATA;
+	if ((fattr->valid & NFS_ATTR_FATTR) == 0)
+		return 0;
+	return nfs_refresh_inode_locked(inode, fattr);
+}
+
+/**
+ * nfs_post_op_update_inode - try to update the inode attribute cache
+ * @inode - pointer to inode
+ * @fattr - updated attributes
+ *
+ * After an operation that has changed the inode metadata, mark the
+ * attribute cache as being invalid, then try to update it.
+ *
+ * NB: if the server didn't return any post op attributes, this
+ * function will force the retrieval of attributes before the next
+ * NFS request.  Thus it should be used only for operations that
+ * are expected to change one or more attributes, to avoid
+ * unnecessary NFS requests and trips through nfs_update_inode().
+ */
+int nfs_post_op_update_inode(struct inode *inode, struct nfs_fattr *fattr)
+{
+	int status;
+
+	spin_lock(&inode->i_lock);
+	status = nfs_post_op_update_inode_locked(inode, fattr);
+	spin_unlock(&inode->i_lock);
+	return status;
+}
+
+/**
+ * nfs_post_op_update_inode_force_wcc - try to update the inode attribute cache
+ * @inode - pointer to inode
+ * @fattr - updated attributes
+ *
+ * After an operation that has changed the inode metadata, mark the
+ * attribute cache as being invalid, then try to update it. Fake up
+ * weak cache consistency data, if none exist.
+ *
+ * This function is mainly designed to be used by the ->write_done() functions.
+ */
+int nfs_post_op_update_inode_force_wcc(struct inode *inode, struct nfs_fattr *fattr)
+{
+	int status;
+
+	spin_lock(&inode->i_lock);
+	/* Don't do a WCC update if these attributes are already stale */
+	if ((fattr->valid & NFS_ATTR_FATTR) == 0 ||
+			!nfs_inode_attrs_need_update(inode, fattr)) {
+		fattr->valid &= ~(NFS_ATTR_FATTR_PRECHANGE
+				| NFS_ATTR_FATTR_PRESIZE
+				| NFS_ATTR_FATTR_PREMTIME
+				| NFS_ATTR_FATTR_PRECTIME);
+		goto out_noforce;
+	}
+	if ((fattr->valid & NFS_ATTR_FATTR_CHANGE) != 0 &&
+			(fattr->valid & NFS_ATTR_FATTR_PRECHANGE) == 0) {
+		fattr->pre_change_attr = inode->i_version;
+		fattr->valid |= NFS_ATTR_FATTR_PRECHANGE;
+	}
+	if ((fattr->valid & NFS_ATTR_FATTR_CTIME) != 0 &&
+			(fattr->valid & NFS_ATTR_FATTR_PRECTIME) == 0) {
+		memcpy(&fattr->pre_ctime, &inode->i_ctime, sizeof(fattr->pre_ctime));
+		fattr->valid |= NFS_ATTR_FATTR_PRECTIME;
+	}
+	if ((fattr->valid & NFS_ATTR_FATTR_MTIME) != 0 &&
+			(fattr->valid & NFS_ATTR_FATTR_PREMTIME) == 0) {
+		memcpy(&fattr->pre_mtime, &inode->i_mtime, sizeof(fattr->pre_mtime));
+		fattr->valid |= NFS_ATTR_FATTR_PREMTIME;
+	}
+	if ((fattr->valid & NFS_ATTR_FATTR_SIZE) != 0 &&
+			(fattr->valid & NFS_ATTR_FATTR_PRESIZE) == 0) {
+		fattr->pre_size = i_size_read(inode);
+		fattr->valid |= NFS_ATTR_FATTR_PRESIZE;
+	}
+out_noforce:
+	status = nfs_post_op_update_inode_locked(inode, fattr);
+	spin_unlock(&inode->i_lock);
+	return status;
+}
+
+/*
+ * Many nfs protocol calls return the new file attributes after
+ * an operation.  Here we update the inode to reflect the state
+ * of the server's inode.
+ *
+ * This is a bit tricky because we have to make sure all dirty pages
+ * have been sent off to the server before calling invalidate_inode_pages.
+ * To make sure no other process adds more write requests while we try
+ * our best to flush them, we make them sleep during the attribute refresh.
+ *
+ * A very similar scenario holds for the dir cache.
+ */
+static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
+{
+	struct nfs_server *server;
+	struct nfs_inode *nfsi = NFS_I(inode);
+	loff_t cur_isize, new_isize;
+	unsigned long invalid = 0;
+	unsigned long now = jiffies;
+	unsigned long save_cache_validity;
+
+	dfprintk(VFS, "NFS: %s(%s/%ld fh_crc=0x%08x ct=%d info=0x%x)\n",
+			__func__, inode->i_sb->s_id, inode->i_ino,
+			nfs_display_fhandle_hash(NFS_FH(inode)),
+			atomic_read(&inode->i_count), fattr->valid);
+
+	if ((fattr->valid & NFS_ATTR_FATTR_FILEID) && nfsi->fileid != fattr->fileid)
+		goto out_fileid;
+
+	/*
+	 * Make sure the inode's type hasn't changed.
+	 */
+	if ((fattr->valid & NFS_ATTR_FATTR_TYPE) && (inode->i_mode & S_IFMT) != (fattr->mode & S_IFMT))
+		goto out_changed;
+
+	server = NFS_SERVER(inode);
+	/* Update the fsid? */
+	if (S_ISDIR(inode->i_mode) && (fattr->valid & NFS_ATTR_FATTR_FSID) &&
+			!nfs_fsid_equal(&server->fsid, &fattr->fsid) &&
+			!IS_AUTOMOUNT(inode))
+		server->fsid = fattr->fsid;
+
+	/*
+	 * Update the read time so we don't revalidate too often.
+	 */
+	nfsi->read_cache_jiffies = fattr->time_start;
+
+	save_cache_validity = nfsi->cache_validity;
+	nfsi->cache_validity &= ~(NFS_INO_INVALID_ATTR
+			| NFS_INO_INVALID_ATIME
+			| NFS_INO_REVAL_FORCED
+			| NFS_INO_REVAL_PAGECACHE);
+
+	/* Do atomic weak cache consistency updates */
+	invalid |= nfs_wcc_update_inode(inode, fattr);
+
+	/* More cache consistency checks */
+	if (fattr->valid & NFS_ATTR_FATTR_CHANGE) {
+		if (inode->i_version != fattr->change_attr) {
+			dprintk("NFS: change_attr change on server for file %s/%ld\n",
+					inode->i_sb->s_id, inode->i_ino);
+			invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
+			if (S_ISDIR(inode->i_mode))
+				nfs_force_lookup_revalidate(inode);
+			inode->i_version = fattr->change_attr;
+		}
+	} else if (server->caps & NFS_CAP_CHANGE_ATTR)
+		invalid |= save_cache_validity;
+
+	if (fattr->valid & NFS_ATTR_FATTR_MTIME) {
+		/* NFSv2/v3: Check if the mtime agrees */
+		if (!timespec_equal(&inode->i_mtime, &fattr->mtime)) {
+			dprintk("NFS: mtime change on server for file %s/%ld\n",
+					inode->i_sb->s_id, inode->i_ino);
+			invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA;
+			if (S_ISDIR(inode->i_mode))
+				nfs_force_lookup_revalidate(inode);
+			memcpy(&inode->i_mtime, &fattr->mtime, sizeof(inode->i_mtime));
+		}
+	} else if (server->caps & NFS_CAP_MTIME)
+		invalid |= save_cache_validity & (NFS_INO_INVALID_ATTR
+				| NFS_INO_INVALID_DATA
+				| NFS_INO_REVAL_PAGECACHE
+				| NFS_INO_REVAL_FORCED);
+
+	if (fattr->valid & NFS_ATTR_FATTR_CTIME) {
+		/* If ctime has changed we should definitely clear access+acl caches */
+		if (!timespec_equal(&inode->i_ctime, &fattr->ctime)) {
+			invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
+			/* and probably clear data for a directory too as utimes can cause
+			 * havoc with our cache.
+			 */
+			if (S_ISDIR(inode->i_mode)) {
+				invalid |= NFS_INO_INVALID_DATA;
+				nfs_force_lookup_revalidate(inode);
+			}
+			memcpy(&inode->i_ctime, &fattr->ctime, sizeof(inode->i_ctime));
+		}
+	} else if (server->caps & NFS_CAP_CTIME)
+		invalid |= save_cache_validity & (NFS_INO_INVALID_ATTR
+				| NFS_INO_INVALID_ACCESS
+				| NFS_INO_INVALID_ACL
+				| NFS_INO_REVAL_FORCED);
+
+	/* Check if our cached file size is stale */
+	if (fattr->valid & NFS_ATTR_FATTR_SIZE) {
+		new_isize = nfs_size_to_loff_t(fattr->size);
+		cur_isize = i_size_read(inode);
+		if (new_isize != cur_isize) {
+			/* Do we perhaps have any outstanding writes, or has
+			 * the file grown beyond our last write? */
+			if ((nfsi->npages == 0 && !test_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) ||
+			     new_isize > cur_isize) {
+				i_size_write(inode, new_isize);
+				invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA;
+			}
+			dprintk("NFS: isize change on server for file %s/%ld "
+					"(%Ld to %Ld)\n",
+					inode->i_sb->s_id,
+					inode->i_ino,
+					(long long)cur_isize,
+					(long long)new_isize);
+		}
+	} else
+		invalid |= save_cache_validity & (NFS_INO_INVALID_ATTR
+				| NFS_INO_REVAL_PAGECACHE
+				| NFS_INO_REVAL_FORCED);
+
+
+	if (fattr->valid & NFS_ATTR_FATTR_ATIME)
+		memcpy(&inode->i_atime, &fattr->atime, sizeof(inode->i_atime));
+	else if (server->caps & NFS_CAP_ATIME)
+		invalid |= save_cache_validity & (NFS_INO_INVALID_ATIME
+				| NFS_INO_REVAL_FORCED);
+
+	if (fattr->valid & NFS_ATTR_FATTR_MODE) {
+		if ((inode->i_mode & S_IALLUGO) != (fattr->mode & S_IALLUGO)) {
+			umode_t newmode = inode->i_mode & S_IFMT;
+			newmode |= fattr->mode & S_IALLUGO;
+			inode->i_mode = newmode;
+			invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
+		}
+	} else if (server->caps & NFS_CAP_MODE)
+		invalid |= save_cache_validity & (NFS_INO_INVALID_ATTR
+				| NFS_INO_INVALID_ACCESS
+				| NFS_INO_INVALID_ACL
+				| NFS_INO_REVAL_FORCED);
+
+	if (fattr->valid & NFS_ATTR_FATTR_OWNER) {
+		if (inode->i_uid != fattr->uid) {
+			invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
+			inode->i_uid = fattr->uid;
+		}
+	} else if (server->caps & NFS_CAP_OWNER)
+		invalid |= save_cache_validity & (NFS_INO_INVALID_ATTR
+				| NFS_INO_INVALID_ACCESS
+				| NFS_INO_INVALID_ACL
+				| NFS_INO_REVAL_FORCED);
+
+	if (fattr->valid & NFS_ATTR_FATTR_GROUP) {
+		if (inode->i_gid != fattr->gid) {
+			invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
+			inode->i_gid = fattr->gid;
+		}
+	} else if (server->caps & NFS_CAP_OWNER_GROUP)
+		invalid |= save_cache_validity & (NFS_INO_INVALID_ATTR
+				| NFS_INO_INVALID_ACCESS
+				| NFS_INO_INVALID_ACL
+				| NFS_INO_REVAL_FORCED);
+
+	if (fattr->valid & NFS_ATTR_FATTR_NLINK) {
+		if (inode->i_nlink != fattr->nlink) {
+			invalid |= NFS_INO_INVALID_ATTR;
+			if (S_ISDIR(inode->i_mode))
+				invalid |= NFS_INO_INVALID_DATA;
+			set_nlink(inode, fattr->nlink);
+		}
+	} else if (server->caps & NFS_CAP_NLINK)
+		invalid |= save_cache_validity & (NFS_INO_INVALID_ATTR
+				| NFS_INO_REVAL_FORCED);
+
+	if (fattr->valid & NFS_ATTR_FATTR_SPACE_USED) {
+		/*
+		 * report the blocks in 512byte units
+		 */
+		inode->i_blocks = nfs_calc_block_size(fattr->du.nfs3.used);
+ 	}
+	if (fattr->valid & NFS_ATTR_FATTR_BLOCKS_USED)
+		inode->i_blocks = fattr->du.nfs2.blocks;
+
+	/* Update attrtimeo value if we're out of the unstable period */
+	if (invalid & NFS_INO_INVALID_ATTR) {
+		nfs_inc_stats(inode, NFSIOS_ATTRINVALIDATE);
+		nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
+		nfsi->attrtimeo_timestamp = now;
+		nfsi->attr_gencount = nfs_inc_attr_generation_counter();
+	} else {
+		if (!time_in_range_open(now, nfsi->attrtimeo_timestamp, nfsi->attrtimeo_timestamp + nfsi->attrtimeo)) {
+			if ((nfsi->attrtimeo <<= 1) > NFS_MAXATTRTIMEO(inode))
+				nfsi->attrtimeo = NFS_MAXATTRTIMEO(inode);
+			nfsi->attrtimeo_timestamp = now;
+		}
+	}
+	invalid &= ~NFS_INO_INVALID_ATTR;
+	/* Don't invalidate the data if we were to blame */
+	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)
+				|| S_ISLNK(inode->i_mode)))
+		invalid &= ~NFS_INO_INVALID_DATA;
+	if (!nfs_have_delegation(inode, FMODE_READ) ||
+			(save_cache_validity & NFS_INO_REVAL_FORCED))
+		nfsi->cache_validity |= invalid;
+
+	return 0;
+ out_changed:
+	/*
+	 * Big trouble! The inode has become a different object.
+	 */
+	printk(KERN_DEBUG "NFS: %s: inode %ld mode changed, %07o to %07o\n",
+			__func__, inode->i_ino, inode->i_mode, fattr->mode);
+ out_err:
+	/*
+	 * No need to worry about unhashing the dentry, as the
+	 * lookup validation will know that the inode is bad.
+	 * (But we fall through to invalidate the caches.)
+	 */
+	nfs_invalidate_inode(inode);
+	return -ESTALE;
+
+ out_fileid:
+	printk(KERN_ERR "NFS: server %s error: fileid changed\n"
+		"fsid %s: expected fileid 0x%Lx, got 0x%Lx\n",
+		NFS_SERVER(inode)->nfs_client->cl_hostname, inode->i_sb->s_id,
+		(long long)nfsi->fileid, (long long)fattr->fileid);
+	goto out_err;
+}
+
+
+#ifdef CONFIG_NFS_V4
+
+/*
+ * Clean out any remaining NFSv4 state that might be left over due
+ * to open() calls that passed nfs_atomic_lookup, but failed to call
+ * nfs_open().
+ */
+void nfs4_evict_inode(struct inode *inode)
+{
+	truncate_inode_pages(&inode->i_data, 0);
+	end_writeback(inode);
+	pnfs_return_layout(inode);
+	pnfs_destroy_layout(NFS_I(inode));
+	/* If we are holding a delegation, return it! */
+	nfs_inode_return_delegation_noreclaim(inode);
+	/* First call standard NFS clear_inode() code */
+	nfs_clear_inode(inode);
+}
+#endif
+
+struct inode *nfs_alloc_inode(struct super_block *sb)
+{
+	struct nfs_inode *nfsi;
+	nfsi = (struct nfs_inode *)kmem_cache_alloc(nfs_inode_cachep, GFP_KERNEL);
+	if (!nfsi)
+		return NULL;
+	nfsi->flags = 0UL;
+	nfsi->cache_validity = 0UL;
+#ifdef CONFIG_NFS_V3_ACL
+	nfsi->acl_access = ERR_PTR(-EAGAIN);
+	nfsi->acl_default = ERR_PTR(-EAGAIN);
+#endif
+#ifdef CONFIG_NFS_V4
+	nfsi->nfs4_acl = NULL;
+#endif /* CONFIG_NFS_V4 */
+	return &nfsi->vfs_inode;
+}
+
+static void nfs_i_callback(struct rcu_head *head)
+{
+	struct inode *inode = container_of(head, struct inode, i_rcu);
+	kmem_cache_free(nfs_inode_cachep, NFS_I(inode));
+}
+
+void nfs_destroy_inode(struct inode *inode)
+{
+	call_rcu(&inode->i_rcu, nfs_i_callback);
+}
+
+static inline void nfs4_init_once(struct nfs_inode *nfsi)
+{
+#ifdef CONFIG_NFS_V4
+	INIT_LIST_HEAD(&nfsi->open_states);
+	nfsi->delegation = NULL;
+	nfsi->delegation_state = 0;
+	init_rwsem(&nfsi->rwsem);
+	nfsi->layout = NULL;
+	atomic_set(&nfsi->commits_outstanding, 0);
+#endif
+}
+
+static void init_once(void *foo)
+{
+	struct nfs_inode *nfsi = (struct nfs_inode *) foo;
+
+	inode_init_once(&nfsi->vfs_inode);
+	INIT_LIST_HEAD(&nfsi->open_files);
+	INIT_LIST_HEAD(&nfsi->access_cache_entry_lru);
+	INIT_LIST_HEAD(&nfsi->access_cache_inode_lru);
+	INIT_LIST_HEAD(&nfsi->commit_list);
+	nfsi->npages = 0;
+	nfsi->ncommit = 0;
+	atomic_set(&nfsi->silly_count, 1);
+	INIT_HLIST_HEAD(&nfsi->silly_list);
+	init_waitqueue_head(&nfsi->waitqueue);
+	nfs4_init_once(nfsi);
+}
+
+static int __init nfs_init_inodecache(void)
+{
+	nfs_inode_cachep = kmem_cache_create("nfs_inode_cache",
+					     sizeof(struct nfs_inode),
+					     0, (SLAB_RECLAIM_ACCOUNT|
+						SLAB_MEM_SPREAD),
+					     init_once);
+	if (nfs_inode_cachep == NULL)
+		return -ENOMEM;
+
+	return 0;
+}
+
+static void nfs_destroy_inodecache(void)
+{
+	kmem_cache_destroy(nfs_inode_cachep);
+}
+
+struct workqueue_struct *nfsiod_workqueue;
+
+/*
+ * start up the nfsiod workqueue
+ */
+static int nfsiod_start(void)
+{
+	struct workqueue_struct *wq;
+	dprintk("RPC:       creating workqueue nfsiod\n");
+	wq = alloc_workqueue("nfsiod", WQ_MEM_RECLAIM, 0);
+	if (wq == NULL)
+		return -ENOMEM;
+	nfsiod_workqueue = wq;
+	return 0;
+}
+
+/*
+ * Destroy the nfsiod workqueue
+ */
+static void nfsiod_stop(void)
+{
+	struct workqueue_struct *wq;
+
+	wq = nfsiod_workqueue;
+	if (wq == NULL)
+		return;
+	nfsiod_workqueue = NULL;
+	destroy_workqueue(wq);
+}
+
+int nfs_net_id;
+EXPORT_SYMBOL_GPL(nfs_net_id);
+
+static int nfs_net_init(struct net *net)
+{
+	nfs_clients_init(net);
+	return nfs_dns_resolver_cache_init(net);
+}
+
+static void nfs_net_exit(struct net *net)
+{
+	nfs_dns_resolver_cache_destroy(net);
+	nfs_cleanup_cb_ident_idr(net);
+}
+
+static struct pernet_operations nfs_net_ops = {
+	.init = nfs_net_init,
+	.exit = nfs_net_exit,
+	.id   = &nfs_net_id,
+	.size = sizeof(struct nfs_net),
+};
+
+/*
+ * Initialize NFS
+ */
+static int __init init_nfs_fs(void)
+{
+	int err;
+
+	err = nfs_idmap_init();
+	if (err < 0)
+		goto out10;
+
+	err = nfs_dns_resolver_init();
+	if (err < 0)
+		goto out9;
+
+	err = register_pernet_subsys(&nfs_net_ops);
+	if (err < 0)
+		goto out8;
+
+	err = nfs_fscache_register();
+	if (err < 0)
+		goto out7;
+
+	err = nfsiod_start();
+	if (err)
+		goto out6;
+
+	err = nfs_fs_proc_init();
+	if (err)
+		goto out5;
+
+	err = nfs_init_nfspagecache();
+	if (err)
+		goto out4;
+
+	err = nfs_init_inodecache();
+	if (err)
+		goto out3;
+
+	err = nfs_init_readpagecache();
+	if (err)
+		goto out2;
+
+	err = nfs_init_writepagecache();
+	if (err)
+		goto out1;
+
+	err = nfs_init_directcache();
+	if (err)
+		goto out0;
+
+#ifdef CONFIG_PROC_FS
+	rpc_proc_register(&init_net, &nfs_rpcstat);
+#endif
+	if ((err = register_nfs_fs()) != 0)
+		goto out;
+	return 0;
+out:
+#ifdef CONFIG_PROC_FS
+	rpc_proc_unregister(&init_net, "nfs");
+#endif
+	nfs_destroy_directcache();
+out0:
+	nfs_destroy_writepagecache();
+out1:
+	nfs_destroy_readpagecache();
+out2:
+	nfs_destroy_inodecache();
+out3:
+	nfs_destroy_nfspagecache();
+out4:
+	nfs_fs_proc_exit();
+out5:
+	nfsiod_stop();
+out6:
+	nfs_fscache_unregister();
+out7:
+	unregister_pernet_subsys(&nfs_net_ops);
+out8:
+	nfs_dns_resolver_destroy();
+out9:
+	nfs_idmap_quit();
+out10:
+	return err;
+}
+
+static void __exit exit_nfs_fs(void)
+{
+	nfs_destroy_directcache();
+	nfs_destroy_writepagecache();
+	nfs_destroy_readpagecache();
+	nfs_destroy_inodecache();
+	nfs_destroy_nfspagecache();
+	nfs_fscache_unregister();
+	unregister_pernet_subsys(&nfs_net_ops);
+	nfs_dns_resolver_destroy();
+	nfs_idmap_quit();
+#ifdef CONFIG_PROC_FS
+	rpc_proc_unregister(&init_net, "nfs");
+#endif
+	unregister_nfs_fs();
+	nfs_fs_proc_exit();
+	nfsiod_stop();
+}
+
+/* Not quite true; I just maintain it */
+MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
+MODULE_LICENSE("GPL");
+module_param(enable_ino64, bool, 0644);
+
+module_init(init_nfs_fs)
+module_exit(exit_nfs_fs)