X-Git-Url: http://ftp.safe.ca/?p=safe%2Fjmp%2Flinux-2.6;a=blobdiff_plain;f=fs%2Fnfsd%2Fvfs.c;h=ebf56c6040caa450676f66b2101b87cf1d4de180;hp=46f59d5365a0d49986512c54a25ecdc6daeb54f1;hb=9d2a3f31d6d7832cd441eeda08bc2266cdd5d972;hpb=5477549161480432d053565d2720f08626baf9e3

diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 46f59d5..ebf56c6 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -83,7 +83,6 @@ struct raparm_hbucket {
 	spinlock_t		pb_lock;
 } ____cacheline_aligned_in_smp;
 
-static struct raparms *		raparml;
 #define RAPARM_HASH_BITS	4
 #define RAPARM_HASH_SIZE	(1<<RAPARM_HASH_BITS)
 #define RAPARM_HASH_MASK	(RAPARM_HASH_SIZE-1)
@@ -117,10 +116,15 @@ nfsd_cross_mnt(struct svc_rqst *rqstp, struct dentry **dpp,
 	}
 	if ((exp->ex_flags & NFSEXP_CROSSMOUNT) || EX_NOHIDE(exp2)) {
 		/* successfully crossed mount point */
-		exp_put(exp);
-		*expp = exp2;
+		/*
+		 * This is subtle: dentry is *not* under mnt at this point.
+		 * The only reason we are safe is that original mnt is pinned
+		 * down by exp, so we should dput before putting exp.
+		 */
 		dput(dentry);
 		*dpp = mounts;
+		exp_put(exp);
+		*expp = exp2;
 	} else {
 		exp_put(exp2);
 		dput(mounts);
@@ -144,7 +148,7 @@ nfsd_lookup_dentry(struct svc_rqst *rqstp, struct svc_fh *fhp,
 	dprintk("nfsd: nfsd_lookup(fh %s, %.*s)\n", SVCFH_fmt(fhp), len,name);
 
 	/* Obtain dentry and export. */
-	err = fh_verify(rqstp, fhp, S_IFDIR, MAY_EXEC);
+	err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_EXEC);
 	if (err)
 		return err;
 
@@ -262,15 +266,14 @@ nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, struct iattr *iap,
 {
 	struct dentry	*dentry;
 	struct inode	*inode;
-	int		accmode = MAY_SATTR;
+	int		accmode = NFSD_MAY_SATTR;
 	int		ftype = 0;
-	int		imode;
 	__be32		err;
 	int		host_err;
 	int		size_change = 0;
 
 	if (iap->ia_valid & (ATTR_ATIME | ATTR_MTIME | ATTR_SIZE))
-		accmode |= MAY_WRITE|MAY_OWNER_OVERRIDE;
+		accmode |= NFSD_MAY_WRITE|NFSD_MAY_OWNER_OVERRIDE;
 	if (iap->ia_valid & ATTR_SIZE)
 		ftype = S_IFREG;
 
@@ -332,7 +335,8 @@ nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, struct iattr *iap,
 	 */
 	if (iap->ia_valid & ATTR_SIZE) {
 		if (iap->ia_size < inode->i_size) {
-			err = nfsd_permission(rqstp, fhp->fh_export, dentry, MAY_TRUNC|MAY_OWNER_OVERRIDE);
+			err = nfsd_permission(rqstp, fhp->fh_export, dentry,
+					NFSD_MAY_TRUNC|NFSD_MAY_OWNER_OVERRIDE);
 			if (err)
 				goto out;
 		}
@@ -357,28 +361,29 @@ nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, struct iattr *iap,
 			put_write_access(inode);
 			goto out_nfserr;
 		}
-		DQUOT_INIT(inode);
+		vfs_dq_init(inode);
 	}
 
-	imode = inode->i_mode;
+	/* sanitize the mode change */
 	if (iap->ia_valid & ATTR_MODE) {
 		iap->ia_mode &= S_IALLUGO;
-		imode = iap->ia_mode |= (imode & ~S_IALLUGO);
-		/* if changing uid/gid revoke setuid/setgid in mode */
-		if ((iap->ia_valid & ATTR_UID) && iap->ia_uid != inode->i_uid) {
-			iap->ia_valid |= ATTR_KILL_PRIV;
+		iap->ia_mode |= (inode->i_mode & ~S_IALLUGO);
+	}
+
+	/* Revoke setuid/setgid on chown */
+	if (!S_ISDIR(inode->i_mode) &&
+	    (((iap->ia_valid & ATTR_UID) && iap->ia_uid != inode->i_uid) ||
+	     ((iap->ia_valid & ATTR_GID) && iap->ia_gid != inode->i_gid))) {
+		iap->ia_valid |= ATTR_KILL_PRIV;
+		if (iap->ia_valid & ATTR_MODE) {
+			/* we're setting mode too, just clear the s*id bits */
 			iap->ia_mode &= ~S_ISUID;
+			if (iap->ia_mode & S_IXGRP)
+				iap->ia_mode &= ~S_ISGID;
+		} else {
+			/* set ATTR_KILL_* bits and let VFS handle it */
+			iap->ia_valid |= (ATTR_KILL_SUID | ATTR_KILL_SGID);
 		}
-		if ((iap->ia_valid & ATTR_GID) && iap->ia_gid != inode->i_gid)
-			iap->ia_mode &= ~S_ISGID;
-	} else {
-		/*
-		 * Revoke setuid/setgid bit on chown/chgrp
-		 */
-		if ((iap->ia_valid & ATTR_UID) && iap->ia_uid != inode->i_uid)
-			iap->ia_valid |= ATTR_KILL_SUID | ATTR_KILL_PRIV;
-		if ((iap->ia_valid & ATTR_GID) && iap->ia_gid != inode->i_gid)
-			iap->ia_valid |= ATTR_KILL_SGID;
 	}
 
 	/* Change the attributes. */
@@ -411,6 +416,7 @@ out_nfserr:
 static ssize_t nfsd_getxattr(struct dentry *dentry, char *key, void **buf)
 {
 	ssize_t buflen;
+	ssize_t ret;
 
 	buflen = vfs_getxattr(dentry, key, NULL, 0);
 	if (buflen <= 0)
@@ -420,7 +426,10 @@ static ssize_t nfsd_getxattr(struct dentry *dentry, char *key, void **buf)
 	if (!*buf)
 		return -ENOMEM;
 
-	return vfs_getxattr(dentry, key, *buf, buflen);
+	ret = vfs_getxattr(dentry, key, *buf, buflen);
+	if (ret < 0)
+		kfree(*buf);
+	return ret;
 }
 #endif
 
@@ -463,7 +472,7 @@ nfsd4_set_nfs4_acl(struct svc_rqst *rqstp, struct svc_fh *fhp,
 	unsigned int flags = 0;
 
 	/* Get inode */
-	error = fh_verify(rqstp, fhp, 0 /* S_IFREG */, MAY_SATTR);
+	error = fh_verify(rqstp, fhp, 0 /* S_IFREG */, NFSD_MAY_SATTR);
 	if (error)
 		return error;
 
@@ -564,20 +573,20 @@ struct accessmap {
 	int		how;
 };
 static struct accessmap	nfs3_regaccess[] = {
-    {	NFS3_ACCESS_READ,	MAY_READ			},
-    {	NFS3_ACCESS_EXECUTE,	MAY_EXEC			},
-    {	NFS3_ACCESS_MODIFY,	MAY_WRITE|MAY_TRUNC		},
-    {	NFS3_ACCESS_EXTEND,	MAY_WRITE			},
+    {	NFS3_ACCESS_READ,	NFSD_MAY_READ			},
+    {	NFS3_ACCESS_EXECUTE,	NFSD_MAY_EXEC			},
+    {	NFS3_ACCESS_MODIFY,	NFSD_MAY_WRITE|NFSD_MAY_TRUNC	},
+    {	NFS3_ACCESS_EXTEND,	NFSD_MAY_WRITE			},
 
     {	0,			0				}
 };
 
 static struct accessmap	nfs3_diraccess[] = {
-    {	NFS3_ACCESS_READ,	MAY_READ			},
-    {	NFS3_ACCESS_LOOKUP,	MAY_EXEC			},
-    {	NFS3_ACCESS_MODIFY,	MAY_EXEC|MAY_WRITE|MAY_TRUNC	},
-    {	NFS3_ACCESS_EXTEND,	MAY_EXEC|MAY_WRITE		},
-    {	NFS3_ACCESS_DELETE,	MAY_REMOVE			},
+    {	NFS3_ACCESS_READ,	NFSD_MAY_READ			},
+    {	NFS3_ACCESS_LOOKUP,	NFSD_MAY_EXEC			},
+    {	NFS3_ACCESS_MODIFY,	NFSD_MAY_EXEC|NFSD_MAY_WRITE|NFSD_MAY_TRUNC},
+    {	NFS3_ACCESS_EXTEND,	NFSD_MAY_EXEC|NFSD_MAY_WRITE	},
+    {	NFS3_ACCESS_DELETE,	NFSD_MAY_REMOVE			},
 
     {	0,			0				}
 };
@@ -590,10 +599,10 @@ static struct accessmap	nfs3_anyaccess[] = {
 	 * mainly at mode bits, and we make sure to ignore read-only
 	 * filesystem checks
 	 */
-    {	NFS3_ACCESS_READ,	MAY_READ			},
-    {	NFS3_ACCESS_EXECUTE,	MAY_EXEC			},
-    {	NFS3_ACCESS_MODIFY,	MAY_WRITE|MAY_LOCAL_ACCESS	},
-    {	NFS3_ACCESS_EXTEND,	MAY_WRITE|MAY_LOCAL_ACCESS	},
+    {	NFS3_ACCESS_READ,	NFSD_MAY_READ			},
+    {	NFS3_ACCESS_EXECUTE,	NFSD_MAY_EXEC			},
+    {	NFS3_ACCESS_MODIFY,	NFSD_MAY_WRITE|NFSD_MAY_LOCAL_ACCESS	},
+    {	NFS3_ACCESS_EXTEND,	NFSD_MAY_WRITE|NFSD_MAY_LOCAL_ACCESS	},
 
     {	0,			0				}
 };
@@ -607,7 +616,7 @@ nfsd_access(struct svc_rqst *rqstp, struct svc_fh *fhp, u32 *access, u32 *suppor
 	u32			query, result = 0, sresult = 0;
 	__be32			error;
 
-	error = fh_verify(rqstp, fhp, 0, MAY_NOP);
+	error = fh_verify(rqstp, fhp, 0, NFSD_MAY_NOP);
 	if (error)
 		goto out;
 
@@ -668,6 +677,7 @@ __be32
 nfsd_open(struct svc_rqst *rqstp, struct svc_fh *fhp, int type,
 			int access, struct file **filp)
 {
+	const struct cred *cred = current_cred();
 	struct dentry	*dentry;
 	struct inode	*inode;
 	int		flags = O_RDONLY|O_LARGEFILE;
@@ -679,7 +689,7 @@ nfsd_open(struct svc_rqst *rqstp, struct svc_fh *fhp, int type,
 	 * and (hopefully) checked permission - so allow OWNER_OVERRIDE
 	 * in case a chmod has now revoked permission.
 	 */
-	err = fh_verify(rqstp, fhp, type, access | MAY_OWNER_OVERRIDE);
+	err = fh_verify(rqstp, fhp, type, access | NFSD_MAY_OWNER_OVERRIDE);
 	if (err)
 		goto out;
 
@@ -690,7 +700,7 @@ nfsd_open(struct svc_rqst *rqstp, struct svc_fh *fhp, int type,
 	 * or any access when mandatory locking enabled
 	 */
 	err = nfserr_perm;
-	if (IS_APPEND(inode) && (access & MAY_WRITE))
+	if (IS_APPEND(inode) && (access & NFSD_MAY_WRITE))
 		goto out;
 	/*
 	 * We must ignore files (but only files) which might have mandatory
@@ -707,22 +717,22 @@ nfsd_open(struct svc_rqst *rqstp, struct svc_fh *fhp, int type,
 	 * Check to see if there are any leases on this file.
 	 * This may block while leases are broken.
 	 */
-	host_err = break_lease(inode, O_NONBLOCK | ((access & MAY_WRITE) ? FMODE_WRITE : 0));
+	host_err = break_lease(inode, O_NONBLOCK | ((access & NFSD_MAY_WRITE) ? FMODE_WRITE : 0));
 	if (host_err == -EWOULDBLOCK)
 		host_err = -ETIMEDOUT;
 	if (host_err) /* NOMEM or WOULDBLOCK */
 		goto out_nfserr;
 
-	if (access & MAY_WRITE) {
-		if (access & MAY_READ)
+	if (access & NFSD_MAY_WRITE) {
+		if (access & NFSD_MAY_READ)
 			flags = O_RDWR|O_LARGEFILE;
 		else
 			flags = O_WRONLY|O_LARGEFILE;
 
-		DQUOT_INIT(inode);
+		vfs_dq_init(inode);
 	}
 	*filp = dentry_open(dget(dentry), mntget(fhp->fh_export->ex_path.mnt),
-				flags);
+			    flags, cred);
 	if (IS_ERR(*filp))
 		host_err = PTR_ERR(*filp);
 out_nfserr:
@@ -760,7 +770,6 @@ static inline int nfsd_dosync(struct file *filp, struct dentry *dp,
 
 	return err;
 }
-	
 
 static int
 nfsd_sync(struct file *filp)
@@ -957,7 +966,7 @@ static void kill_suid(struct dentry *dentry)
 static __be32
 nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file,
 				loff_t offset, struct kvec *vec, int vlen,
-	   			unsigned long cnt, int *stablep)
+				unsigned long *cnt, int *stablep)
 {
 	struct svc_export	*exp;
 	struct dentry		*dentry;
@@ -966,12 +975,13 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file,
 	__be32			err = 0;
 	int			host_err;
 	int			stable = *stablep;
+	int			use_wgather;
 
 #ifdef MSNFS
 	err = nfserr_perm;
 
 	if ((fhp->fh_export->ex_flags & NFSEXP_MSNFS) &&
-		(!lock_may_write(file->f_path.dentry->d_inode, offset, cnt)))
+		(!lock_may_write(file->f_path.dentry->d_inode, offset, *cnt)))
 		goto out;
 #endif
 
@@ -984,26 +994,31 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file,
 	 *  -	the sync export option has been set, or
 	 *  -	the client requested O_SYNC behavior (NFSv3 feature).
 	 *  -   The file system doesn't support fsync().
-	 * When gathered writes have been configured for this volume,
+	 * When NFSv2 gathered writes have been configured for this volume,
 	 * flushing the data to disk is handled separately below.
 	 */
+	use_wgather = (rqstp->rq_vers == 2) && EX_WGATHER(exp);
 
-	if (file->f_op->fsync == 0) {/* COMMIT3 cannot work */
+	if (!file->f_op->fsync) {/* COMMIT3 cannot work */
 	       stable = 2;
 	       *stablep = 2; /* FILE_SYNC */
 	}
 
 	if (!EX_ISSYNC(exp))
 		stable = 0;
-	if (stable && !EX_WGATHER(exp))
+	if (stable && !use_wgather) {
+		spin_lock(&file->f_lock);
 		file->f_flags |= O_SYNC;
+		spin_unlock(&file->f_lock);
+	}
 
 	/* Write the data. */
 	oldfs = get_fs(); set_fs(KERNEL_DS);
 	host_err = vfs_writev(file, (struct iovec __user *)vec, vlen, &offset);
 	set_fs(oldfs);
 	if (host_err >= 0) {
-		nfsdstats.io_write += cnt;
+		*cnt = host_err;
+		nfsdstats.io_write += host_err;
 		fsnotify_modify(file->f_path.dentry);
 	}
 
@@ -1011,7 +1026,7 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file,
 	if (host_err >= 0 && (inode->i_mode & (S_ISUID | S_ISGID)))
 		kill_suid(dentry);
 
-	if (host_err >= 0 && stable) {
+	if (host_err >= 0 && stable && use_wgather) {
 		static ino_t	last_ino;
 		static dev_t	last_dev;
 
@@ -1027,21 +1042,16 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file,
 		 * nice and simple solution (IMHO), and it seems to
 		 * work:-)
 		 */
-		if (EX_WGATHER(exp)) {
-			if (atomic_read(&inode->i_writecount) > 1
-			    || (last_ino == inode->i_ino && last_dev == inode->i_sb->s_dev)) {
-				dprintk("nfsd: write defer %d\n", task_pid_nr(current));
-				msleep(10);
-				dprintk("nfsd: write resume %d\n", task_pid_nr(current));
-			}
+		if (atomic_read(&inode->i_writecount) > 1
+		    || (last_ino == inode->i_ino && last_dev == inode->i_sb->s_dev)) {
+			dprintk("nfsd: write defer %d\n", task_pid_nr(current));
+			msleep(10);
+			dprintk("nfsd: write resume %d\n", task_pid_nr(current));
+		}
 
-			if (inode->i_state & I_DIRTY) {
-				dprintk("nfsd: write sync %d\n", task_pid_nr(current));
-				host_err=nfsd_sync(file);
-			}
-#if 0
-			wake_up(&inode->i_wait);
-#endif
+		if (inode->i_state & I_DIRTY) {
+			dprintk("nfsd: write sync %d\n", task_pid_nr(current));
+			host_err=nfsd_sync(file);
 		}
 		last_ino = inode->i_ino;
 		last_dev = inode->i_sb->s_dev;
@@ -1050,7 +1060,7 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file,
 	dprintk("nfsd: write complete host_err=%d\n", host_err);
 	if (host_err >= 0)
 		err = 0;
-	else 
+	else
 		err = nfserrno(host_err);
 out:
 	return err;
@@ -1070,12 +1080,12 @@ nfsd_read(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file,
 
 	if (file) {
 		err = nfsd_permission(rqstp, fhp->fh_export, fhp->fh_dentry,
-				MAY_READ|MAY_OWNER_OVERRIDE);
+				NFSD_MAY_READ|NFSD_MAY_OWNER_OVERRIDE);
 		if (err)
 			goto out;
 		err = nfsd_vfs_read(rqstp, fhp, file, offset, vec, vlen, count);
 	} else {
-		err = nfsd_open(rqstp, fhp, S_IFREG, MAY_READ, &file);
+		err = nfsd_open(rqstp, fhp, S_IFREG, NFSD_MAY_READ, &file);
 		if (err)
 			goto out;
 		err = nfsd_vfs_read(rqstp, fhp, file, offset, vec, vlen, count);
@@ -1092,20 +1102,20 @@ out:
  */
 __be32
 nfsd_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file,
-		loff_t offset, struct kvec *vec, int vlen, unsigned long cnt,
+		loff_t offset, struct kvec *vec, int vlen, unsigned long *cnt,
 		int *stablep)
 {
 	__be32			err = 0;
 
 	if (file) {
 		err = nfsd_permission(rqstp, fhp->fh_export, fhp->fh_dentry,
-				MAY_WRITE|MAY_OWNER_OVERRIDE);
+				NFSD_MAY_WRITE|NFSD_MAY_OWNER_OVERRIDE);
 		if (err)
 			goto out;
 		err = nfsd_vfs_write(rqstp, fhp, file, offset, vec, vlen, cnt,
 				stablep);
 	} else {
-		err = nfsd_open(rqstp, fhp, S_IFREG, MAY_WRITE, &file);
+		err = nfsd_open(rqstp, fhp, S_IFREG, NFSD_MAY_WRITE, &file);
 		if (err)
 			goto out;
 
@@ -1137,7 +1147,8 @@ nfsd_commit(struct svc_rqst *rqstp, struct svc_fh *fhp,
 	if ((u64)count > ~(u64)offset)
 		return nfserr_inval;
 
-	if ((err = nfsd_open(rqstp, fhp, S_IFREG, MAY_WRITE, &file)) != 0)
+	err = nfsd_open(rqstp, fhp, S_IFREG, NFSD_MAY_WRITE, &file);
+	if (err)
 		return err;
 	if (EX_ISSYNC(fhp->fh_export)) {
 		if (file->f_op && file->f_op->fsync) {
@@ -1152,7 +1163,7 @@ nfsd_commit(struct svc_rqst *rqstp, struct svc_fh *fhp,
 }
 #endif /* CONFIG_NFSD_V3 */
 
-__be32
+static __be32
 nfsd_create_setattr(struct svc_rqst *rqstp, struct svc_fh *resfhp,
 			struct iattr *iap)
 {
@@ -1165,13 +1176,28 @@ nfsd_create_setattr(struct svc_rqst *rqstp, struct svc_fh *resfhp,
 	 * send along the gid on create when it tries to implement
 	 * setgid directories via NFS:
 	 */
-	if (current->fsuid != 0)
+	if (current_fsuid() != 0)
 		iap->ia_valid &= ~(ATTR_UID|ATTR_GID);
 	if (iap->ia_valid)
 		return nfsd_setattr(rqstp, resfhp, iap, 0, (time_t)0);
 	return 0;
 }
 
+/* HPUX client sometimes creates a file in mode 000, and sets size to 0.
+ * setting size to 0 may fail for some specific file systems by the permission
+ * checking which requires WRITE permission but the mode is 000.
+ * we ignore the resizing(to 0) on the just new created file, since the size is
+ * 0 after file created.
+ *
+ * call this only after vfs_create() is called.
+ * */
+static void
+nfsd_check_ignore_resizing(struct iattr *iap)
+{
+	if ((iap->ia_valid & ATTR_SIZE) && (iap->ia_size == 0))
+		iap->ia_valid &= ~ATTR_SIZE;
+}
+
 /*
  * Create a file (regular, directory, device, fifo); UNIX sockets 
  * not yet implemented.
@@ -1198,7 +1224,7 @@ nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp,
 	if (isdotent(fname, flen))
 		goto out;
 
-	err = fh_verify(rqstp, fhp, S_IFDIR, MAY_CREATE);
+	err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_CREATE);
 	if (err)
 		goto out;
 
@@ -1206,7 +1232,7 @@ nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp,
 	dirp = dentry->d_inode;
 
 	err = nfserr_notdir;
-	if(!dirp->i_op || !dirp->i_op->lookup)
+	if (!dirp->i_op->lookup)
 		goto out;
 	/*
 	 * Check whether the response file handle has been verified yet.
@@ -1249,6 +1275,17 @@ nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp,
 		iap->ia_mode = 0;
 	iap->ia_mode = (iap->ia_mode & S_IALLUGO) | type;
 
+	err = nfserr_inval;
+	if (!S_ISREG(type) && !S_ISDIR(type) && !special_file(type)) {
+		printk(KERN_WARNING "nfsd: bad file type %o in nfsd_create\n",
+		       type);
+		goto out;
+	}
+
+	host_err = mnt_want_write(fhp->fh_export->ex_path.mnt);
+	if (host_err)
+		goto out_nfserr;
+
 	/*
 	 * Get the dir op function pointer.
 	 */
@@ -1256,6 +1293,8 @@ nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp,
 	switch (type) {
 	case S_IFREG:
 		host_err = vfs_create(dirp, dchild, iap->ia_mode, NULL);
+		if (!host_err)
+			nfsd_check_ignore_resizing(iap);
 		break;
 	case S_IFDIR:
 		host_err = vfs_mkdir(dirp, dchild, iap->ia_mode);
@@ -1266,22 +1305,21 @@ nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp,
 	case S_IFSOCK:
 		host_err = vfs_mknod(dirp, dchild, iap->ia_mode, rdev);
 		break;
-	default:
-	        printk("nfsd: bad file type %o in nfsd_create\n", type);
-		host_err = -EINVAL;
 	}
-	if (host_err < 0)
+	if (host_err < 0) {
+		mnt_drop_write(fhp->fh_export->ex_path.mnt);
 		goto out_nfserr;
+	}
 
 	if (EX_ISSYNC(fhp->fh_export)) {
 		err = nfserrno(nfsd_sync_dir(dentry));
 		write_inode_now(dchild->d_inode, 1);
 	}
 
-
 	err2 = nfsd_create_setattr(rqstp, resfhp, iap);
 	if (err2)
 		err = err2;
+	mnt_drop_write(fhp->fh_export->ex_path.mnt);
 	/*
 	 * Update the file handle to get the new inode info.
 	 */
@@ -1322,7 +1360,7 @@ nfsd_create_v3(struct svc_rqst *rqstp, struct svc_fh *fhp,
 		goto out;
 	if (!(iap->ia_valid & ATTR_MODE))
 		iap->ia_mode = 0;
-	err = fh_verify(rqstp, fhp, S_IFDIR, MAY_CREATE);
+	err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_CREATE);
 	if (err)
 		goto out;
 
@@ -1332,7 +1370,7 @@ nfsd_create_v3(struct svc_rqst *rqstp, struct svc_fh *fhp,
 	/* Get all the sanity checks out of the way before
 	 * we lock the parent. */
 	err = nfserr_notdir;
-	if(!dirp->i_op || !dirp->i_op->lookup)
+	if (!dirp->i_op->lookup)
 		goto out;
 	fh_lock_nested(fhp, I_MUTEX_PARENT);
 
@@ -1359,6 +1397,9 @@ nfsd_create_v3(struct svc_rqst *rqstp, struct svc_fh *fhp,
 		v_atime = verifier[1]&0x7fffffff;
 	}
 	
+	host_err = mnt_want_write(fhp->fh_export->ex_path.mnt);
+	if (host_err)
+		goto out_nfserr;
 	if (dchild->d_inode) {
 		err = 0;
 
@@ -1390,12 +1431,15 @@ nfsd_create_v3(struct svc_rqst *rqstp, struct svc_fh *fhp,
 		case NFS3_CREATE_GUARDED:
 			err = nfserr_exist;
 		}
+		mnt_drop_write(fhp->fh_export->ex_path.mnt);
 		goto out;
 	}
 
 	host_err = vfs_create(dirp, dchild, iap->ia_mode, NULL);
-	if (host_err < 0)
+	if (host_err < 0) {
+		mnt_drop_write(fhp->fh_export->ex_path.mnt);
 		goto out_nfserr;
+	}
 	if (created)
 		*created = 1;
 
@@ -1404,6 +1448,8 @@ nfsd_create_v3(struct svc_rqst *rqstp, struct svc_fh *fhp,
 		/* setattr will sync the child (or not) */
 	}
 
+	nfsd_check_ignore_resizing(iap);
+
 	if (createmode == NFS3_CREATE_EXCLUSIVE) {
 		/* Cram the verifier into atime/mtime */
 		iap->ia_valid = ATTR_MTIME|ATTR_ATIME
@@ -1420,6 +1466,7 @@ nfsd_create_v3(struct svc_rqst *rqstp, struct svc_fh *fhp,
 	if (err2)
 		err = err2;
 
+	mnt_drop_write(fhp->fh_export->ex_path.mnt);
 	/*
 	 * Update the filehandle to get the new inode info.
 	 */
@@ -1452,7 +1499,7 @@ nfsd_readlink(struct svc_rqst *rqstp, struct svc_fh *fhp, char *buf, int *lenp)
 	__be32		err;
 	int		host_err;
 
-	err = fh_verify(rqstp, fhp, S_IFLNK, MAY_NOP);
+	err = fh_verify(rqstp, fhp, S_IFLNK, NFSD_MAY_NOP);
 	if (err)
 		goto out;
 
@@ -1460,7 +1507,7 @@ nfsd_readlink(struct svc_rqst *rqstp, struct svc_fh *fhp, char *buf, int *lenp)
 	inode = dentry->d_inode;
 
 	err = nfserr_inval;
-	if (!inode->i_op || !inode->i_op->readlink)
+	if (!inode->i_op->readlink)
 		goto out;
 
 	touch_atime(fhp->fh_export->ex_path.mnt, dentry);
@@ -1498,7 +1545,6 @@ nfsd_symlink(struct svc_rqst *rqstp, struct svc_fh *fhp,
 	struct dentry	*dentry, *dnew;
 	__be32		err, cerr;
 	int		host_err;
-	umode_t		mode;
 
 	err = nfserr_noent;
 	if (!flen || !plen)
@@ -1507,7 +1553,7 @@ nfsd_symlink(struct svc_rqst *rqstp, struct svc_fh *fhp,
 	if (isdotent(fname, flen))
 		goto out;
 
-	err = fh_verify(rqstp, fhp, S_IFDIR, MAY_CREATE);
+	err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_CREATE);
 	if (err)
 		goto out;
 	fh_lock(fhp);
@@ -1517,10 +1563,9 @@ nfsd_symlink(struct svc_rqst *rqstp, struct svc_fh *fhp,
 	if (IS_ERR(dnew))
 		goto out_nfserr;
 
-	mode = S_IALLUGO;
-	/* Only the MODE ATTRibute is even vaguely meaningful */
-	if (iap && (iap->ia_valid & ATTR_MODE))
-		mode = iap->ia_mode & S_IALLUGO;
+	host_err = mnt_want_write(fhp->fh_export->ex_path.mnt);
+	if (host_err)
+		goto out_nfserr;
 
 	if (unlikely(path[plen] != 0)) {
 		char *path_alloced = kmalloc(plen+1, GFP_KERNEL);
@@ -1529,11 +1574,11 @@ nfsd_symlink(struct svc_rqst *rqstp, struct svc_fh *fhp,
 		else {
 			strncpy(path_alloced, path, plen);
 			path_alloced[plen] = 0;
-			host_err = vfs_symlink(dentry->d_inode, dnew, path_alloced, mode);
+			host_err = vfs_symlink(dentry->d_inode, dnew, path_alloced);
 			kfree(path_alloced);
 		}
 	} else
-		host_err = vfs_symlink(dentry->d_inode, dnew, path, mode);
+		host_err = vfs_symlink(dentry->d_inode, dnew, path);
 
 	if (!host_err) {
 		if (EX_ISSYNC(fhp->fh_export))
@@ -1542,6 +1587,8 @@ nfsd_symlink(struct svc_rqst *rqstp, struct svc_fh *fhp,
 	err = nfserrno(host_err);
 	fh_unlock(fhp);
 
+	mnt_drop_write(fhp->fh_export->ex_path.mnt);
+
 	cerr = fh_compose(resfhp, fhp->fh_export, dnew, fhp);
 	dput(dnew);
 	if (err==0) err = cerr;
@@ -1566,10 +1613,10 @@ nfsd_link(struct svc_rqst *rqstp, struct svc_fh *ffhp,
 	__be32		err;
 	int		host_err;
 
-	err = fh_verify(rqstp, ffhp, S_IFDIR, MAY_CREATE);
+	err = fh_verify(rqstp, ffhp, S_IFDIR, NFSD_MAY_CREATE);
 	if (err)
 		goto out;
-	err = fh_verify(rqstp, tfhp, -S_IFDIR, MAY_NOP);
+	err = fh_verify(rqstp, tfhp, -S_IFDIR, NFSD_MAY_NOP);
 	if (err)
 		goto out;
 
@@ -1592,6 +1639,11 @@ nfsd_link(struct svc_rqst *rqstp, struct svc_fh *ffhp,
 	dold = tfhp->fh_dentry;
 	dest = dold->d_inode;
 
+	host_err = mnt_want_write(tfhp->fh_export->ex_path.mnt);
+	if (host_err) {
+		err = nfserrno(host_err);
+		goto out_dput;
+	}
 	host_err = vfs_link(dold, dirp, dnew);
 	if (!host_err) {
 		if (EX_ISSYNC(ffhp->fh_export)) {
@@ -1605,7 +1657,8 @@ nfsd_link(struct svc_rqst *rqstp, struct svc_fh *ffhp,
 		else
 			err = nfserrno(host_err);
 	}
-
+	mnt_drop_write(tfhp->fh_export->ex_path.mnt);
+out_dput:
 	dput(dnew);
 out_unlock:
 	fh_unlock(ffhp);
@@ -1630,10 +1683,10 @@ nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen,
 	__be32		err;
 	int		host_err;
 
-	err = fh_verify(rqstp, ffhp, S_IFDIR, MAY_REMOVE);
+	err = fh_verify(rqstp, ffhp, S_IFDIR, NFSD_MAY_REMOVE);
 	if (err)
 		goto out;
-	err = fh_verify(rqstp, tfhp, S_IFDIR, MAY_CREATE);
+	err = fh_verify(rqstp, tfhp, S_IFDIR, NFSD_MAY_CREATE);
 	if (err)
 		goto out;
 
@@ -1678,13 +1731,20 @@ nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen,
 	if (ndentry == trap)
 		goto out_dput_new;
 
-#ifdef MSNFS
-	if ((ffhp->fh_export->ex_flags & NFSEXP_MSNFS) &&
+	if (svc_msnfs(ffhp) &&
 		((atomic_read(&odentry->d_count) > 1)
 		 || (atomic_read(&ndentry->d_count) > 1))) {
 			host_err = -EPERM;
-	} else
-#endif
+			goto out_dput_new;
+	}
+
+	host_err = -EXDEV;
+	if (ffhp->fh_export->ex_path.mnt != tfhp->fh_export->ex_path.mnt)
+		goto out_dput_new;
+	host_err = mnt_want_write(ffhp->fh_export->ex_path.mnt);
+	if (host_err)
+		goto out_dput_new;
+
 	host_err = vfs_rename(fdir, odentry, tdir, ndentry);
 	if (!host_err && EX_ISSYNC(tfhp->fh_export)) {
 		host_err = nfsd_sync_dir(tdentry);
@@ -1692,6 +1752,8 @@ nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen,
 			host_err = nfsd_sync_dir(fdentry);
 	}
 
+	mnt_drop_write(ffhp->fh_export->ex_path.mnt);
+
  out_dput_new:
 	dput(ndentry);
  out_dput_old:
@@ -1728,7 +1790,7 @@ nfsd_unlink(struct svc_rqst *rqstp, struct svc_fh *fhp, int type,
 	err = nfserr_acces;
 	if (!flen || isdotent(fname, flen))
 		goto out;
-	err = fh_verify(rqstp, fhp, S_IFDIR, MAY_REMOVE);
+	err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_REMOVE);
 	if (err)
 		goto out;
 
@@ -1750,6 +1812,10 @@ nfsd_unlink(struct svc_rqst *rqstp, struct svc_fh *fhp, int type,
 	if (!type)
 		type = rdentry->d_inode->i_mode & S_IFMT;
 
+	host_err = mnt_want_write(fhp->fh_export->ex_path.mnt);
+	if (host_err)
+		goto out_nfserr;
+
 	if (type != S_IFDIR) { /* It's UNLINK */
 #ifdef MSNFS
 		if ((fhp->fh_export->ex_flags & NFSEXP_MSNFS) &&
@@ -1765,10 +1831,12 @@ nfsd_unlink(struct svc_rqst *rqstp, struct svc_fh *fhp, int type,
 	dput(rdentry);
 
 	if (host_err)
-		goto out_nfserr;
+		goto out_drop;
 	if (EX_ISSYNC(fhp->fh_export))
 		host_err = nfsd_sync_dir(dentry);
 
+out_drop:
+	mnt_drop_write(fhp->fh_export->ex_path.mnt);
 out_nfserr:
 	err = nfserrno(host_err);
 out:
@@ -1776,6 +1844,126 @@ out:
 }
 
 /*
+ * We do this buffering because we must not call back into the file
+ * system's ->lookup() method from the filldir callback. That may well
+ * deadlock a number of file systems.
+ *
+ * This is based heavily on the implementation of same in XFS.
+ */
+struct buffered_dirent {
+	u64		ino;
+	loff_t		offset;
+	int		namlen;
+	unsigned int	d_type;
+	char		name[];
+};
+
+struct readdir_data {
+	char		*dirent;
+	size_t		used;
+	int		full;
+};
+
+static int nfsd_buffered_filldir(void *__buf, const char *name, int namlen,
+				 loff_t offset, u64 ino, unsigned int d_type)
+{
+	struct readdir_data *buf = __buf;
+	struct buffered_dirent *de = (void *)(buf->dirent + buf->used);
+	unsigned int reclen;
+
+	reclen = ALIGN(sizeof(struct buffered_dirent) + namlen, sizeof(u64));
+	if (buf->used + reclen > PAGE_SIZE) {
+		buf->full = 1;
+		return -EINVAL;
+	}
+
+	de->namlen = namlen;
+	de->offset = offset;
+	de->ino = ino;
+	de->d_type = d_type;
+	memcpy(de->name, name, namlen);
+	buf->used += reclen;
+
+	return 0;
+}
+
+static __be32 nfsd_buffered_readdir(struct file *file, filldir_t func,
+				    struct readdir_cd *cdp, loff_t *offsetp)
+{
+	struct readdir_data buf;
+	struct buffered_dirent *de;
+	int host_err;
+	int size;
+	loff_t offset;
+
+	buf.dirent = (void *)__get_free_page(GFP_KERNEL);
+	if (!buf.dirent)
+		return nfserrno(-ENOMEM);
+
+	offset = *offsetp;
+
+	while (1) {
+		struct inode *dir_inode = file->f_path.dentry->d_inode;
+		unsigned int reclen;
+
+		cdp->err = nfserr_eof; /* will be cleared on successful read */
+		buf.used = 0;
+		buf.full = 0;
+
+		host_err = vfs_readdir(file, nfsd_buffered_filldir, &buf);
+		if (buf.full)
+			host_err = 0;
+
+		if (host_err < 0)
+			break;
+
+		size = buf.used;
+
+		if (!size)
+			break;
+
+		/*
+		 * Various filldir functions may end up calling back into
+		 * lookup_one_len() and the file system's ->lookup() method.
+		 * These expect i_mutex to be held, as it would within readdir.
+		 */
+		host_err = mutex_lock_killable(&dir_inode->i_mutex);
+		if (host_err)
+			break;
+
+		de = (struct buffered_dirent *)buf.dirent;
+		while (size > 0) {
+			offset = de->offset;
+
+			if (func(cdp, de->name, de->namlen, de->offset,
+				 de->ino, de->d_type))
+				break;
+
+			if (cdp->err != nfs_ok)
+				break;
+
+			reclen = ALIGN(sizeof(*de) + de->namlen,
+				       sizeof(u64));
+			size -= reclen;
+			de = (struct buffered_dirent *)((char *)de + reclen);
+		}
+		mutex_unlock(&dir_inode->i_mutex);
+		if (size > 0) /* We bailed out early */
+			break;
+
+		offset = vfs_llseek(file, 0, SEEK_CUR);
+	}
+
+	free_page((unsigned long)(buf.dirent));
+
+	if (host_err)
+		return nfserrno(host_err);
+
+	*offsetp = offset;
+	return cdp->err;
+}
+
+/*
  * Read entries from a directory.
  * The  NFSv3/4 verifier we ignore for now.
  */
@@ -1784,11 +1972,10 @@ nfsd_readdir(struct svc_rqst *rqstp, struct svc_fh *fhp, loff_t *offsetp,
 	     struct readdir_cd *cdp, filldir_t func)
 {
 	__be32		err;
-	int 		host_err;
 	struct file	*file;
 	loff_t		offset = *offsetp;
 
-	err = nfsd_open(rqstp, fhp, S_IFDIR, MAY_READ, &file);
+	err = nfsd_open(rqstp, fhp, S_IFDIR, NFSD_MAY_READ, &file);
 	if (err)
 		goto out;
 
@@ -1798,21 +1985,7 @@ nfsd_readdir(struct svc_rqst *rqstp, struct svc_fh *fhp, loff_t *offsetp,
 		goto out_close;
 	}
 
-	/*
-	 * Read the directory entries. This silly loop is necessary because
-	 * readdir() is not guaranteed to fill up the entire buffer, but
-	 * may choose to do less.
-	 */
-
-	do {
-		cdp->err = nfserr_eof; /* will be cleared on successful read */
-		host_err = vfs_readdir(file, func, cdp);
-	} while (host_err >=0 && cdp->err == nfs_ok);
-	if (host_err)
-		err = nfserrno(host_err);
-	else
-		err = cdp->err;
-	*offsetp = vfs_llseek(file, 0, 1);
+	err = nfsd_buffered_readdir(file, func, cdp, offsetp);
 
 	if (err == nfserr_eof || err == nfserr_toosmall)
 		err = nfs_ok; /* can still be found in ->err */
@@ -1827,9 +2000,9 @@ out:
  * N.B. After this call fhp needs an fh_put
  */
 __be32
-nfsd_statfs(struct svc_rqst *rqstp, struct svc_fh *fhp, struct kstatfs *stat)
+nfsd_statfs(struct svc_rqst *rqstp, struct svc_fh *fhp, struct kstatfs *stat, int access)
 {
-	__be32 err = fh_verify(rqstp, fhp, 0, MAY_NOP);
+	__be32 err = fh_verify(rqstp, fhp, 0, NFSD_MAY_NOP | access);
 	if (!err && vfs_statfs(fhp->fh_dentry,stat))
 		err = nfserr_io;
 	return err;
@@ -1850,41 +2023,42 @@ nfsd_permission(struct svc_rqst *rqstp, struct svc_export *exp,
 	struct inode	*inode = dentry->d_inode;
 	int		err;
 
-	if (acc == MAY_NOP)
+	if (acc == NFSD_MAY_NOP)
 		return 0;
 #if 0
 	dprintk("nfsd: permission 0x%x%s%s%s%s%s%s%s mode 0%o%s%s%s\n",
 		acc,
-		(acc & MAY_READ)?	" read"  : "",
-		(acc & MAY_WRITE)?	" write" : "",
-		(acc & MAY_EXEC)?	" exec"  : "",
-		(acc & MAY_SATTR)?	" sattr" : "",
-		(acc & MAY_TRUNC)?	" trunc" : "",
-		(acc & MAY_LOCK)?	" lock"  : "",
-		(acc & MAY_OWNER_OVERRIDE)? " owneroverride" : "",
+		(acc & NFSD_MAY_READ)?	" read"  : "",
+		(acc & NFSD_MAY_WRITE)?	" write" : "",
+		(acc & NFSD_MAY_EXEC)?	" exec"  : "",
+		(acc & NFSD_MAY_SATTR)?	" sattr" : "",
+		(acc & NFSD_MAY_TRUNC)?	" trunc" : "",
+		(acc & NFSD_MAY_LOCK)?	" lock"  : "",
+		(acc & NFSD_MAY_OWNER_OVERRIDE)? " owneroverride" : "",
 		inode->i_mode,
 		IS_IMMUTABLE(inode)?	" immut" : "",
 		IS_APPEND(inode)?	" append" : "",
-		IS_RDONLY(inode)?	" ro" : "");
+		__mnt_is_readonly(exp->ex_path.mnt)?	" ro" : "");
 	dprintk("      owner %d/%d user %d/%d\n",
-		inode->i_uid, inode->i_gid, current->fsuid, current->fsgid);
+		inode->i_uid, inode->i_gid, current_fsuid(), current_fsgid());
 #endif
 
 	/* Normally we reject any write/sattr etc access on a read-only file
 	 * system.  But if it is IRIX doing check on write-access for a 
 	 * device special file, we ignore rofs.
 	 */
-	if (!(acc & MAY_LOCAL_ACCESS))
-		if (acc & (MAY_WRITE | MAY_SATTR | MAY_TRUNC)) {
-			if (exp_rdonly(rqstp, exp) || IS_RDONLY(inode))
+	if (!(acc & NFSD_MAY_LOCAL_ACCESS))
+		if (acc & (NFSD_MAY_WRITE | NFSD_MAY_SATTR | NFSD_MAY_TRUNC)) {
+			if (exp_rdonly(rqstp, exp) ||
+			    __mnt_is_readonly(exp->ex_path.mnt))
 				return nfserr_rofs;
-			if (/* (acc & MAY_WRITE) && */ IS_IMMUTABLE(inode))
+			if (/* (acc & NFSD_MAY_WRITE) && */ IS_IMMUTABLE(inode))
 				return nfserr_perm;
 		}
-	if ((acc & MAY_TRUNC) && IS_APPEND(inode))
+	if ((acc & NFSD_MAY_TRUNC) && IS_APPEND(inode))
 		return nfserr_perm;
 
-	if (acc & MAY_LOCK) {
+	if (acc & NFSD_MAY_LOCK) {
 		/* If we cannot rely on authentication in NLM requests,
 		 * just allow locks, otherwise require read permission, or
 		 * ownership
@@ -1892,7 +2066,7 @@ nfsd_permission(struct svc_rqst *rqstp, struct svc_export *exp,
 		if (exp->ex_flags & NFSEXP_NOAUTHNLM)
 			return 0;
 		else
-			acc = MAY_READ | MAY_OWNER_OVERRIDE;
+			acc = NFSD_MAY_READ | NFSD_MAY_OWNER_OVERRIDE;
 	}
 	/*
 	 * The file owner always gets access permission for accesses that
@@ -1908,16 +2082,17 @@ nfsd_permission(struct svc_rqst *rqstp, struct svc_export *exp,
 	 * We must trust the client to do permission checking - using "ACCESS"
 	 * with NFSv3.
 	 */
-	if ((acc & MAY_OWNER_OVERRIDE) &&
-	    inode->i_uid == current->fsuid)
+	if ((acc & NFSD_MAY_OWNER_OVERRIDE) &&
+	    inode->i_uid == current_fsuid())
 		return 0;
 
-	err = permission(inode, acc & (MAY_READ|MAY_WRITE|MAY_EXEC), NULL);
+	/* This assumes  NFSD_MAY_{READ,WRITE,EXEC} == MAY_{READ,WRITE,EXEC} */
+	err = inode_permission(inode, acc & (MAY_READ|MAY_WRITE|MAY_EXEC));
 
 	/* Allow read access to binaries even when mode 111 */
 	if (err == -EACCES && S_ISREG(inode->i_mode) &&
-	    acc == (MAY_READ | MAY_OWNER_OVERRIDE))
-		err = permission(inode, MAY_EXEC, NULL);
+	    acc == (NFSD_MAY_READ | NFSD_MAY_OWNER_OVERRIDE))
+		err = inode_permission(inode, MAY_EXEC);
 
 	return err? nfserrno(err) : 0;
 }
@@ -1925,11 +2100,20 @@ nfsd_permission(struct svc_rqst *rqstp, struct svc_export *exp,
 void
 nfsd_racache_shutdown(void)
 {
-	if (!raparml)
-		return;
+	struct raparms *raparm, *last_raparm;
+	unsigned int i;
+
 	dprintk("nfsd: freeing readahead buffers.\n");
-	kfree(raparml);
-	raparml = NULL;
+
+	for (i = 0; i < RAPARM_HASH_SIZE; i++) {
+		raparm = raparm_hash[i].pb_head;
+		while(raparm) {
+			last_raparm = raparm;
+			raparm = raparm->p_next;
+			kfree(last_raparm);
+		}
+		raparm_hash[i].pb_head = NULL;
+	}
 }
 /*
  * Initialize readahead param cache
@@ -1940,35 +2124,38 @@ nfsd_racache_init(int cache_size)
 	int	i;
 	int	j = 0;
 	int	nperbucket;
+	struct raparms **raparm = NULL;
 
 
-	if (raparml)
+	if (raparm_hash[0].pb_head)
 		return 0;
-	if (cache_size < 2*RAPARM_HASH_SIZE)
-		cache_size = 2*RAPARM_HASH_SIZE;
-	raparml = kcalloc(cache_size, sizeof(struct raparms), GFP_KERNEL);
-
-	if (!raparml) {
-		printk(KERN_WARNING
-			"nfsd: Could not allocate memory read-ahead cache.\n");
-		return -ENOMEM;
-	}
+	nperbucket = DIV_ROUND_UP(cache_size, RAPARM_HASH_SIZE);
+	if (nperbucket < 2)
+		nperbucket = 2;
+	cache_size = nperbucket * RAPARM_HASH_SIZE;
 
 	dprintk("nfsd: allocating %d readahead buffers.\n", cache_size);
-	for (i = 0 ; i < RAPARM_HASH_SIZE ; i++) {
-		raparm_hash[i].pb_head = NULL;
+
+	for (i = 0; i < RAPARM_HASH_SIZE; i++) {
 		spin_lock_init(&raparm_hash[i].pb_lock);
-	}
-	nperbucket = DIV_ROUND_UP(cache_size, RAPARM_HASH_SIZE);
-	for (i = 0; i < cache_size - 1; i++) {
-		if (i % nperbucket == 0)
-			raparm_hash[j++].pb_head = raparml + i;
-		if (i % nperbucket < nperbucket-1)
-			raparml[i].p_next = raparml + i + 1;
+
+		raparm = &raparm_hash[i].pb_head;
+		for (j = 0; j < nperbucket; j++) {
+			*raparm = kzalloc(sizeof(struct raparms), GFP_KERNEL);
+			if (!*raparm)
+				goto out_nomem;
+			raparm = &(*raparm)->p_next;
+		}
+		*raparm = NULL;
 	}
 
 	nfsdstats.ra_size = cache_size;
 	return 0;
+
+out_nomem:
+	dprintk("nfsd: kmalloc failed, freeing readahead buffers\n");
+	nfsd_racache_shutdown();
+	return -ENOMEM;
 }
 
 #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
@@ -2013,7 +2200,7 @@ nfsd_set_posix_acl(struct svc_fh *fhp, int type, struct posix_acl *acl)
 	size_t size;
 	int error;
 
-	if (!IS_POSIXACL(inode) || !inode->i_op ||
+	if (!IS_POSIXACL(inode) ||
 	    !inode->i_op->setxattr || !inode->i_op->removexattr)
 		return -EOPNOTSUPP;
 	switch(type) {
@@ -2039,6 +2226,9 @@ nfsd_set_posix_acl(struct svc_fh *fhp, int type, struct posix_acl *acl)
 	} else
 		size = 0;
 
+	error = mnt_want_write(fhp->fh_export->ex_path.mnt);
+	if (error)
+		goto getout;
 	if (size)
 		error = vfs_setxattr(fhp->fh_dentry, name, value, size, 0);
 	else {
@@ -2050,6 +2240,7 @@ nfsd_set_posix_acl(struct svc_fh *fhp, int type, struct posix_acl *acl)
 				error = 0;
 		}
 	}
+	mnt_drop_write(fhp->fh_export->ex_path.mnt);
 
 getout:
 	kfree(value);