1 files changed, 147 insertions, 155 deletions

diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index a293f027326..a11b0e8678e 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -1,7 +1,5 @@
 #define MSNFS	/* HACK HACK */
 /*
- * linux/fs/nfsd/vfs.c
- *
  * File operations used by nfsd. Some of these have been ripped from
  * other parts of the kernel because they weren't exported, others
  * are partial duplicates with added or changed functionality.
@@ -16,48 +14,32 @@
  * Zerocpy NFS support (C) 2002 Hirokazu Takahashi <taka@valinux.co.jp>
  */
 
-#include <linux/string.h>
-#include <linux/time.h>
-#include <linux/errno.h>
 #include <linux/fs.h>
 #include <linux/file.h>
-#include <linux/mount.h>
-#include <linux/major.h>
 #include <linux/splice.h>
-#include <linux/proc_fs.h>
-#include <linux/stat.h>
 #include <linux/fcntl.h>
-#include <linux/net.h>
-#include <linux/unistd.h>
-#include <linux/slab.h>
-#include <linux/pagemap.h>
-#include <linux/in.h>
-#include <linux/module.h>
 #include <linux/namei.h>
-#include <linux/vfs.h>
 #include <linux/delay.h>
-#include <linux/sunrpc/svc.h>
-#include <linux/nfsd/nfsd.h>
-#ifdef CONFIG_NFSD_V3
-#include <linux/nfs3.h>
-#include <linux/nfsd/xdr3.h>
-#endif /* CONFIG_NFSD_V3 */
-#include <linux/nfsd/nfsfh.h>
-#include <linux/quotaops.h>
 #include <linux/fsnotify.h>
-#include <linux/posix_acl.h>
 #include <linux/posix_acl_xattr.h>
 #include <linux/xattr.h>
+#include <linux/jhash.h>
+#include <linux/ima.h>
+#include <asm/uaccess.h>
+#include <linux/exportfs.h>
+#include <linux/writeback.h>
+
+#ifdef CONFIG_NFSD_V3
+#include "xdr3.h"
+#endif /* CONFIG_NFSD_V3 */
+
 #ifdef CONFIG_NFSD_V4
-#include <linux/nfs4.h>
 #include <linux/nfs4_acl.h>
 #include <linux/nfsd_idmap.h>
-#include <linux/security.h>
 #endif /* CONFIG_NFSD_V4 */
-#include <linux/jhash.h>
-#include <linux/ima.h>
 
-#include <asm/uaccess.h>
+#include "nfsd.h"
+#include "vfs.h"
 
 #define NFSDDBG_FACILITY		NFSDDBG_FILEOP
 
@@ -89,12 +71,6 @@ struct raparm_hbucket {
 #define RAPARM_HASH_MASK	(RAPARM_HASH_SIZE-1)
 static struct raparm_hbucket	raparm_hash[RAPARM_HASH_SIZE];
 
-static inline int
-nfsd_v4client(struct svc_rqst *rq)
-{
-    return rq->rq_prog == NFS_PROGRAM && rq->rq_vers == 4;
-}
-
 /* 
  * Called from nfsd_lookup and encode_dirent. Check if we have crossed 
  * a mount point.
@@ -116,8 +92,16 @@ nfsd_cross_mnt(struct svc_rqst *rqstp, struct dentry **dpp,
 
 	exp2 = rqst_exp_get_by_name(rqstp, &path);
 	if (IS_ERR(exp2)) {
-		if (PTR_ERR(exp2) != -ENOENT)
-			err = PTR_ERR(exp2);
+		err = PTR_ERR(exp2);
+		/*
+		 * We normally allow NFS clients to continue
+		 * "underneath" a mountpoint that is not exported.
+		 * The exception is V4ROOT, where no traversal is ever
+		 * allowed without an explicit export of the new
+		 * directory.
+		 */
+		if (err == -ENOENT && !(exp->ex_flags & NFSEXP_V4ROOT))
+			err = 0;
 		path_put(&path);
 		goto out;
 	}
@@ -141,6 +125,53 @@ out:
 	return err;
 }
 
+static void follow_to_parent(struct path *path)
+{
+	struct dentry *dp;
+
+	while (path->dentry == path->mnt->mnt_root && follow_up(path))
+		;
+	dp = dget_parent(path->dentry);
+	dput(path->dentry);
+	path->dentry = dp;
+}
+
+static int nfsd_lookup_parent(struct svc_rqst *rqstp, struct dentry *dparent, struct svc_export **exp, struct dentry **dentryp)
+{
+	struct svc_export *exp2;
+	struct path path = {.mnt = mntget((*exp)->ex_path.mnt),
+			    .dentry = dget(dparent)};
+
+	follow_to_parent(&path);
+
+	exp2 = rqst_exp_parent(rqstp, &path);
+	if (PTR_ERR(exp2) == -ENOENT) {
+		*dentryp = dget(dparent);
+	} else if (IS_ERR(exp2)) {
+		path_put(&path);
+		return PTR_ERR(exp2);
+	} else {
+		*dentryp = dget(path.dentry);
+		exp_put(*exp);
+		*exp = exp2;
+	}
+	path_put(&path);
+	return 0;
+}
+
+/*
+ * For nfsd purposes, we treat V4ROOT exports as though there was an
+ * export at *every* directory.
+ */
+int nfsd_mountpoint(struct dentry *dentry, struct svc_export *exp)
+{
+	if (d_mountpoint(dentry))
+		return 1;
+	if (!(exp->ex_flags & NFSEXP_V4ROOT))
+		return 0;
+	return dentry->d_inode != NULL;
+}
+
 __be32
 nfsd_lookup_dentry(struct svc_rqst *rqstp, struct svc_fh *fhp,
 		   const char *name, unsigned int len,
@@ -169,35 +200,13 @@ nfsd_lookup_dentry(struct svc_rqst *rqstp, struct svc_fh *fhp,
 			dentry = dget(dparent);
 		else if (dparent != exp->ex_path.dentry)
 			dentry = dget_parent(dparent);
-		else if (!EX_NOHIDE(exp))
+		else if (!EX_NOHIDE(exp) && !nfsd_v4client(rqstp))
 			dentry = dget(dparent); /* .. == . just like at / */
 		else {
 			/* checking mountpoint crossing is very different when stepping up */
-			struct svc_export *exp2 = NULL;
-			struct dentry *dp;
-			struct path path = {.mnt = mntget(exp->ex_path.mnt),
-					    .dentry = dget(dparent)};
-
-			while (path.dentry == path.mnt->mnt_root &&
-			       follow_up(&path))
-				;
-			dp = dget_parent(path.dentry);
-			dput(path.dentry);
-			path.dentry = dp;
-
-			exp2 = rqst_exp_parent(rqstp, &path);
-			if (PTR_ERR(exp2) == -ENOENT) {
-				dentry = dget(dparent);
-			} else if (IS_ERR(exp2)) {
-				host_err = PTR_ERR(exp2);
-				path_put(&path);
+			host_err = nfsd_lookup_parent(rqstp, dparent, &exp, &dentry);
+			if (host_err)
 				goto out_nfserr;
-			} else {
-				dentry = dget(path.dentry);
-				exp_put(exp);
-				exp = exp2;
-			}
-			path_put(&path);
 		}
 	} else {
 		fh_lock(fhp);
@@ -208,7 +217,7 @@ nfsd_lookup_dentry(struct svc_rqst *rqstp, struct svc_fh *fhp,
 		/*
 		 * check if we have crossed a mount point ...
 		 */
-		if (d_mountpoint(dentry)) {
+		if (nfsd_mountpoint(dentry, exp)) {
 			if ((host_err = nfsd_cross_mnt(rqstp, &dentry, &exp))) {
 				dput(dentry);
 				goto out_nfserr;
@@ -263,6 +272,32 @@ out:
 	return err;
 }
 
+/*
+ * Commit metadata changes to stable storage.
+ */
+static int
+commit_metadata(struct svc_fh *fhp)
+{
+	struct inode *inode = fhp->fh_dentry->d_inode;
+	const struct export_operations *export_ops = inode->i_sb->s_export_op;
+	int error = 0;
+
+	if (!EX_ISSYNC(fhp->fh_export))
+		return 0;
+
+	if (export_ops->commit_metadata) {
+		error = export_ops->commit_metadata(inode);
+	} else {
+		struct writeback_control wbc = {
+			.sync_mode = WB_SYNC_ALL,
+			.nr_to_write = 0, /* metadata only */
+		};
+
+		error = sync_inode(inode, &wbc);
+	}
+
+	return error;
+}
 
 /*
  * Set various file attributes.
@@ -353,7 +388,7 @@ nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, struct iattr *iap,
 		 * If we are changing the size of the file, then
 		 * we need to break all leases.
 		 */
-		host_err = break_lease(inode, FMODE_WRITE | O_NONBLOCK);
+		host_err = break_lease(inode, O_WRONLY | O_NONBLOCK);
 		if (host_err == -EWOULDBLOCK)
 			host_err = -ETIMEDOUT;
 		if (host_err) /* ENOMEM or EWOULDBLOCK */
@@ -369,7 +404,6 @@ nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, struct iattr *iap,
 			put_write_access(inode);
 			goto out_nfserr;
 		}
-		vfs_dq_init(inode);
 	}
 
 	/* sanitize the mode change */
@@ -726,7 +760,7 @@ 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 & NFSD_MAY_WRITE) ? FMODE_WRITE : 0));
+	host_err = break_lease(inode, O_NONBLOCK | ((access & NFSD_MAY_WRITE) ? O_WRONLY : 0));
 	if (host_err == -EWOULDBLOCK)
 		host_err = -ETIMEDOUT;
 	if (host_err) /* NOMEM or WOULDBLOCK */
@@ -737,15 +771,13 @@ nfsd_open(struct svc_rqst *rqstp, struct svc_fh *fhp, int type,
 			flags = O_RDWR|O_LARGEFILE;
 		else
 			flags = O_WRONLY|O_LARGEFILE;
-
-		vfs_dq_init(inode);
 	}
 	*filp = dentry_open(dget(dentry), mntget(fhp->fh_export->ex_path.mnt),
 			    flags, current_cred());
 	if (IS_ERR(*filp))
 		host_err = PTR_ERR(*filp);
 	else
-		ima_counts_get(*filp);
+		host_err = ima_file_check(*filp, access);
 out_nfserr:
 	err = nfserrno(host_err);
 out:
@@ -763,46 +795,6 @@ nfsd_close(struct file *filp)
 }
 
 /*
- * Sync a file
- * As this calls fsync (not fdatasync) there is no need for a write_inode
- * after it.
- */
-static inline int nfsd_dosync(struct file *filp, struct dentry *dp,
-			      const struct file_operations *fop)
-{
-	struct inode *inode = dp->d_inode;
-	int (*fsync) (struct file *, struct dentry *, int);
-	int err;
-
-	err = filemap_fdatawrite(inode->i_mapping);
-	if (err == 0 && fop && (fsync = fop->fsync))
-		err = fsync(filp, dp, 0);
-	if (err == 0)
-		err = filemap_fdatawait(inode->i_mapping);
-
-	return err;
-}
-
-static int
-nfsd_sync(struct file *filp)
-{
-        int err;
-	struct inode *inode = filp->f_path.dentry->d_inode;
-	dprintk("nfsd: sync file %s\n", filp->f_path.dentry->d_name.name);
-	mutex_lock(&inode->i_mutex);
-	err=nfsd_dosync(filp, filp->f_path.dentry, filp->f_op);
-	mutex_unlock(&inode->i_mutex);
-
-	return err;
-}
-
-int
-nfsd_sync_dir(struct dentry *dp)
-{
-	return nfsd_dosync(NULL, dp, dp->d_inode->i_fop);
-}
-
-/*
  * Obtain the readahead parameters for the file
  * specified by (dev, ino).
  */
@@ -1005,7 +997,7 @@ static int wait_for_concurrent_writes(struct file *file)
 
 	if (inode->i_state & I_DIRTY) {
 		dprintk("nfsd: write sync %d\n", task_pid_nr(current));
-		err = nfsd_sync(file);
+		err = vfs_fsync(file, file->f_path.dentry, 0);
 	}
 	last_ino = inode->i_ino;
 	last_dev = inode->i_sb->s_dev;
@@ -1153,8 +1145,9 @@ out:
 #ifdef CONFIG_NFSD_V3
 /*
  * Commit all pending writes to stable storage.
- * Strictly speaking, we could sync just the indicated file region here,
- * but there's currently no way we can ask the VFS to do so.
+ *
+ * Note: we only guarantee that data that lies within the range specified
+ * by the 'offset' and 'count' parameters will be synced.
  *
  * Unfortunately we cannot lock the file to make sure we return full WCC
  * data to the client, as locking happens lower down in the filesystem.
@@ -1164,23 +1157,32 @@ nfsd_commit(struct svc_rqst *rqstp, struct svc_fh *fhp,
                loff_t offset, unsigned long count)
 {
 	struct file	*file;
-	__be32		err;
+	loff_t		end = LLONG_MAX;
+	__be32		err = nfserr_inval;
 
-	if ((u64)count > ~(u64)offset)
-		return nfserr_inval;
+	if (offset < 0)
+		goto out;
+	if (count != 0) {
+		end = offset + (loff_t)count - 1;
+		if (end < offset)
+			goto out;
+	}
 
 	err = nfsd_open(rqstp, fhp, S_IFREG, NFSD_MAY_WRITE, &file);
 	if (err)
-		return err;
+		goto out;
 	if (EX_ISSYNC(fhp->fh_export)) {
-		if (file->f_op && file->f_op->fsync) {
-			err = nfserrno(nfsd_sync(file));
-		} else {
+		int err2 = vfs_fsync_range(file, file->f_path.dentry,
+				offset, end, 0);
+
+		if (err2 != -EINVAL)
+			err = nfserrno(err2);
+		else
 			err = nfserr_notsupp;
-		}
 	}
 
 	nfsd_close(file);
+out:
 	return err;
 }
 #endif /* CONFIG_NFSD_V3 */
@@ -1333,12 +1335,14 @@ nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp,
 		goto out_nfserr;
 	}
 
-	if (EX_ISSYNC(fhp->fh_export)) {
-		err = nfserrno(nfsd_sync_dir(dentry));
-		write_inode_now(dchild->d_inode, 1);
-	}
+	err = nfsd_create_setattr(rqstp, resfhp, iap);
 
-	err2 = nfsd_create_setattr(rqstp, resfhp, iap);
+	/*
+	 * nfsd_setattr already committed the child.  Transactional filesystems
+	 * had a chance to commit changes for both parent and child
+	 * simultaneously making the following commit_metadata a noop.
+	 */
+	err2 = nfserrno(commit_metadata(fhp));
 	if (err2)
 		err = err2;
 	mnt_drop_write(fhp->fh_export->ex_path.mnt);
@@ -1370,7 +1374,6 @@ nfsd_create_v3(struct svc_rqst *rqstp, struct svc_fh *fhp,
 	struct dentry	*dentry, *dchild = NULL;
 	struct inode	*dirp;
 	__be32		err;
-	__be32		err2;
 	int		host_err;
 	__u32		v_mtime=0, v_atime=0;
 
@@ -1465,11 +1468,6 @@ nfsd_create_v3(struct svc_rqst *rqstp, struct svc_fh *fhp,
 	if (created)
 		*created = 1;
 
-	if (EX_ISSYNC(fhp->fh_export)) {
-		err = nfserrno(nfsd_sync_dir(dentry));
-		/* setattr will sync the child (or not) */
-	}
-
 	nfsd_check_ignore_resizing(iap);
 
 	if (createmode == NFS3_CREATE_EXCLUSIVE) {
@@ -1484,9 +1482,13 @@ nfsd_create_v3(struct svc_rqst *rqstp, struct svc_fh *fhp,
 	}
 
  set_attr:
-	err2 = nfsd_create_setattr(rqstp, resfhp, iap);
-	if (err2)
-		err = err2;
+	err = nfsd_create_setattr(rqstp, resfhp, iap);
+
+	/*
+	 * nfsd_setattr already committed the child (and possibly also the parent).
+	 */
+	if (!err)
+		err = nfserrno(commit_metadata(fhp));
 
 	mnt_drop_write(fhp->fh_export->ex_path.mnt);
 	/*
@@ -1601,12 +1603,9 @@ nfsd_symlink(struct svc_rqst *rqstp, struct svc_fh *fhp,
 		}
 	} else
 		host_err = vfs_symlink(dentry->d_inode, dnew, path);
-
-	if (!host_err) {
-		if (EX_ISSYNC(fhp->fh_export))
-			host_err = nfsd_sync_dir(dentry);
-	}
 	err = nfserrno(host_err);
+	if (!err)
+		err = nfserrno(commit_metadata(fhp));
 	fh_unlock(fhp);
 
 	mnt_drop_write(fhp->fh_export->ex_path.mnt);
@@ -1668,11 +1667,9 @@ nfsd_link(struct svc_rqst *rqstp, struct svc_fh *ffhp,
 	}
 	host_err = vfs_link(dold, dirp, dnew);
 	if (!host_err) {
-		if (EX_ISSYNC(ffhp->fh_export)) {
-			err = nfserrno(nfsd_sync_dir(ddir));
-			write_inode_now(dest, 1);
-		}
-		err = 0;
+		err = nfserrno(commit_metadata(ffhp));
+		if (!err)
+			err = nfserrno(commit_metadata(tfhp));
 	} else {
 		if (host_err == -EXDEV && rqstp->rq_vers == 2)
 			err = nfserr_acces;
@@ -1768,10 +1765,10 @@ nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen,
 		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);
+	if (!host_err) {
+		host_err = commit_metadata(tfhp);
 		if (!host_err)
-			host_err = nfsd_sync_dir(fdentry);
+			host_err = commit_metadata(ffhp);
 	}
 
 	mnt_drop_write(ffhp->fh_export->ex_path.mnt);
@@ -1852,12 +1849,9 @@ nfsd_unlink(struct svc_rqst *rqstp, struct svc_fh *fhp, int type,
 
 	dput(rdentry);
 
-	if (host_err)
-		goto out_drop;
-	if (EX_ISSYNC(fhp->fh_export))
-		host_err = nfsd_sync_dir(dentry);
+	if (!host_err)
+		host_err = commit_metadata(fhp);
 
-out_drop:
 	mnt_drop_write(fhp->fh_export->ex_path.mnt);
 out_nfserr:
 	err = nfserrno(host_err);
@@ -2124,8 +2118,6 @@ nfsd_permission(struct svc_rqst *rqstp, struct svc_export *exp,
 	 */
 	path.mnt = exp->ex_path.mnt;
 	path.dentry = dentry;
-	err = ima_path_check(&path, acc & (MAY_READ | MAY_WRITE | MAY_EXEC),
-			     IMA_COUNT_LEAVE);
 nfsd_out:
 	return err? nfserrno(err) : 0;
 }