Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull vfs updates from Al Viro:
 "The first vfs pile, with deep apologies for being very late in this
  window.

  Assorted cleanups and fixes, plus a large preparatory part of iov_iter
  work.  There's a lot more of that, but it'll probably go into the next
  merge window - it *does* shape up nicely, removes a lot of
  boilerplate, gets rid of locking inconsistencie between aio_write and
  splice_write and I hope to get Kent's direct-io rewrite merged into
  the same queue, but some of the stuff after this point is having
  (mostly trivial) conflicts with the things already merged into
  mainline and with some I want more testing.

  This one passes LTP and xfstests without regressions, in addition to
  usual beating.  BTW, readahead02 in ltp syscalls testsuite has started
  giving failures since "mm/readahead.c: fix readahead failure for
  memoryless NUMA nodes and limit readahead pages" - might be a false
  positive, might be a real regression..."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits)
  missing bits of "splice: fix racy pipe->buffers uses"
  cifs: fix the race in cifs_writev()
  ceph_sync_{,direct_}write: fix an oops on ceph_osdc_new_request() failure
  kill generic_file_buffered_write()
  ocfs2_file_aio_write(): switch to generic_perform_write()
  ceph_aio_write(): switch to generic_perform_write()
  xfs_file_buffered_aio_write(): switch to generic_perform_write()
  export generic_perform_write(), start getting rid of generic_file_buffer_write()
  generic_file_direct_write(): get rid of ppos argument
  btrfs_file_aio_write(): get rid of ppos
  kill the 5th argument of generic_file_buffered_write()
  kill the 4th argument of __generic_file_aio_write()
  lustre: don't open-code kernel_recvmsg()
  ocfs2: don't open-code kernel_recvmsg()
  drbd: don't open-code kernel_recvmsg()
  constify blk_rq_map_user_iov() and friends
  lustre: switch to kernel_sendmsg()
  ocfs2: don't open-code kernel_sendmsg()
  take iov_iter stuff to mm/iov_iter.c
  process_vm_access: tidy up a bit
  ...

34 files changed, 385 insertions, 699 deletions

diff --git a/fs/bio.c b/fs/bio.c
index b1bc722b89aa..6f0362b77806 100644
--- a/fs/bio.c
+++ b/fs/bio.c
@@ -1002,7 +1002,7 @@ struct bio_map_data {
 };
 
 static void bio_set_map_data(struct bio_map_data *bmd, struct bio *bio,
-			     struct sg_iovec *iov, int iov_count,
+			     const struct sg_iovec *iov, int iov_count,
 			     int is_our_pages)
 {
 	memcpy(bmd->sgvecs, iov, sizeof(struct sg_iovec) * iov_count);
@@ -1022,7 +1022,7 @@ static struct bio_map_data *bio_alloc_map_data(int nr_segs,
 		       sizeof(struct sg_iovec) * iov_count, gfp_mask);
 }
 
-static int __bio_copy_iov(struct bio *bio, struct sg_iovec *iov, int iov_count,
+static int __bio_copy_iov(struct bio *bio, const struct sg_iovec *iov, int iov_count,
 			  int to_user, int from_user, int do_free_page)
 {
 	int ret = 0, i;
@@ -1120,7 +1120,7 @@ EXPORT_SYMBOL(bio_uncopy_user);
  */
 struct bio *bio_copy_user_iov(struct request_queue *q,
 			      struct rq_map_data *map_data,
-			      struct sg_iovec *iov, int iov_count,
+			      const struct sg_iovec *iov, int iov_count,
 			      int write_to_vm, gfp_t gfp_mask)
 {
 	struct bio_map_data *bmd;
@@ -1259,7 +1259,7 @@ EXPORT_SYMBOL(bio_copy_user);
 
 static struct bio *__bio_map_user_iov(struct request_queue *q,
 				      struct block_device *bdev,
-				      struct sg_iovec *iov, int iov_count,
+				      const struct sg_iovec *iov, int iov_count,
 				      int write_to_vm, gfp_t gfp_mask)
 {
 	int i, j;
@@ -1407,7 +1407,7 @@ EXPORT_SYMBOL(bio_map_user);
  *	device. Returns an error pointer in case of error.
  */
 struct bio *bio_map_user_iov(struct request_queue *q, struct block_device *bdev,
-			     struct sg_iovec *iov, int iov_count,
+			     const struct sg_iovec *iov, int iov_count,
 			     int write_to_vm, gfp_t gfp_mask)
 {
 	struct bio *bio;
diff --git a/fs/block_dev.c b/fs/block_dev.c
index ba0d2b05bb78..552a8d13bc32 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -1518,7 +1518,7 @@ ssize_t blkdev_aio_write(struct kiocb *iocb, const struct iovec *iov,
 	BUG_ON(iocb->ki_pos != pos);
 
 	blk_start_plug(&plug);
-	ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos);
+	ret = __generic_file_aio_write(iocb, iov, nr_segs);
 	if (ret > 0) {
 		ssize_t err;
 
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index c5998477fe60..eb742c07e7a4 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -425,13 +425,8 @@ static noinline int btrfs_copy_from_user(loff_t pos, int num_pages,
 		struct page *page = prepared_pages[pg];
 		/*
 		 * Copy data from userspace to the current page
-		 *
-		 * Disable pagefault to avoid recursive lock since
-		 * the pages are already locked
 		 */
-		pagefault_disable();
 		copied = iov_iter_copy_from_user_atomic(page, i, offset, count);
-		pagefault_enable();
 
 		/* Flush processor's dcache for this page */
 		flush_dcache_page(page);
@@ -1665,7 +1660,7 @@ again:
 static ssize_t __btrfs_direct_write(struct kiocb *iocb,
 				    const struct iovec *iov,
 				    unsigned long nr_segs, loff_t pos,
-				    loff_t *ppos, size_t count, size_t ocount)
+				    size_t count, size_t ocount)
 {
 	struct file *file = iocb->ki_filp;
 	struct iov_iter i;
@@ -1674,7 +1669,7 @@ static ssize_t __btrfs_direct_write(struct kiocb *iocb,
 	loff_t endbyte;
 	int err;
 
-	written = generic_file_direct_write(iocb, iov, &nr_segs, pos, ppos,
+	written = generic_file_direct_write(iocb, iov, &nr_segs, pos,
 					    count, ocount);
 
 	if (written < 0 || written == count)
@@ -1693,7 +1688,7 @@ static ssize_t __btrfs_direct_write(struct kiocb *iocb,
 	if (err)
 		goto out;
 	written += written_buffered;
-	*ppos = pos + written_buffered;
+	iocb->ki_pos = pos + written_buffered;
 	invalidate_mapping_pages(file->f_mapping, pos >> PAGE_CACHE_SHIFT,
 				 endbyte >> PAGE_CACHE_SHIFT);
 out:
@@ -1725,7 +1720,6 @@ static ssize_t btrfs_file_aio_write(struct kiocb *iocb,
 	struct file *file = iocb->ki_filp;
 	struct inode *inode = file_inode(file);
 	struct btrfs_root *root = BTRFS_I(inode)->root;
-	loff_t *ppos = &iocb->ki_pos;
 	u64 start_pos;
 	u64 end_pos;
 	ssize_t num_written = 0;
@@ -1796,7 +1790,7 @@ static ssize_t btrfs_file_aio_write(struct kiocb *iocb,
 
 	if (unlikely(file->f_flags & O_DIRECT)) {
 		num_written = __btrfs_direct_write(iocb, iov, nr_segs,
-						   pos, ppos, count, ocount);
+						   pos, count, ocount);
 	} else {
 		struct iov_iter i;
 
@@ -1804,7 +1798,7 @@ static ssize_t btrfs_file_aio_write(struct kiocb *iocb,
 
 		num_written = __btrfs_buffered_write(file, &i, pos);
 		if (num_written > 0)
-			*ppos = pos + num_written;
+			iocb->ki_pos = pos + num_written;
 	}
 
 	mutex_unlock(&inode->i_mutex);
diff --git a/fs/buffer.c b/fs/buffer.c
index 8c53a2b15ecb..9ddb9fc7d923 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -2114,8 +2114,8 @@ EXPORT_SYMBOL(generic_write_end);
  * Returns true if all buffers which correspond to a file portion
  * we want to read are uptodate.
  */
-int block_is_partially_uptodate(struct page *page, read_descriptor_t *desc,
-					unsigned long from)
+int block_is_partially_uptodate(struct page *page, unsigned long from,
+					unsigned long count)
 {
 	unsigned block_start, block_end, blocksize;
 	unsigned to;
@@ -2127,7 +2127,7 @@ int block_is_partially_uptodate(struct page *page, read_descriptor_t *desc,
 
 	head = page_buffers(page);
 	blocksize = head->b_size;
-	to = min_t(unsigned, PAGE_CACHE_SIZE - from, desc->count);
+	to = min_t(unsigned, PAGE_CACHE_SIZE - from, count);
 	to = from + to;
 	if (from < blocksize && to > PAGE_CACHE_SIZE - blocksize)
 		return 0;
diff --git a/fs/cachefiles/bind.c b/fs/cachefiles/bind.c
index 622f4696e484..5b99bafc31d1 100644
--- a/fs/cachefiles/bind.c
+++ b/fs/cachefiles/bind.c
@@ -124,7 +124,6 @@ static int cachefiles_daemon_add_cache(struct cachefiles_cache *cache)
 	/* check parameters */
 	ret = -EOPNOTSUPP;
 	if (!root->d_inode ||
-	    !root->d_inode->i_op ||
 	    !root->d_inode->i_op->lookup ||
 	    !root->d_inode->i_op->mkdir ||
 	    !root->d_inode->i_op->setxattr ||
diff --git a/fs/cachefiles/namei.c b/fs/cachefiles/namei.c
index 6494d9f673aa..c0a681705104 100644
--- a/fs/cachefiles/namei.c
+++ b/fs/cachefiles/namei.c
@@ -779,8 +779,7 @@ struct dentry *cachefiles_get_directory(struct cachefiles_cache *cache,
 	}
 
 	ret = -EPERM;
-	if (!subdir->d_inode->i_op ||
-	    !subdir->d_inode->i_op->setxattr ||
+	if (!subdir->d_inode->i_op->setxattr ||
 	    !subdir->d_inode->i_op->getxattr ||
 	    !subdir->d_inode->i_op->lookup ||
 	    !subdir->d_inode->i_op->mkdir ||
diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index 66075a4ad979..39da1c2efa50 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -601,7 +601,7 @@ ceph_sync_direct_write(struct kiocb *iocb, const struct iovec *iov,
 					    false);
 		if (IS_ERR(req)) {
 			ret = PTR_ERR(req);
-			goto out;
+			break;
 		}
 
 		num_pages = calc_pages_for(page_align, len);
@@ -719,7 +719,7 @@ static ssize_t ceph_sync_write(struct kiocb *iocb, const struct iovec *iov,
 					    false);
 		if (IS_ERR(req)) {
 			ret = PTR_ERR(req);
-			goto out;
+			break;
 		}
 
 		/*
@@ -972,6 +972,7 @@ retry_snap:
 		}
 	} else {
 		loff_t old_size = inode->i_size;
+		struct iov_iter from;
 		/*
 		 * No need to acquire the i_truncate_mutex. Because
 		 * the MDS revokes Fwb caps before sending truncate
@@ -979,9 +980,10 @@ retry_snap:
 		 * are pending vmtruncate. So write and vmtruncate
 		 * can not run at the same time
 		 */
-		written = generic_file_buffered_write(iocb, iov, nr_segs,
-						      pos, &iocb->ki_pos,
-						      count, 0);
+		iov_iter_init(&from, iov, nr_segs, count, 0);
+		written = generic_perform_write(file, &from, pos);
+		if (likely(written >= 0))
+			iocb->ki_pos = pos + written;
 		if (inode->i_size > old_size)
 			ceph_fscache_update_objectsize(inode);
 		mutex_unlock(&inode->i_mutex);
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 2c70cbe35d39..df9c9141c099 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -850,7 +850,6 @@ const struct inode_operations cifs_file_inode_ops = {
 /*	revalidate:cifs_revalidate, */
 	.setattr = cifs_setattr,
 	.getattr = cifs_getattr, /* do we need this anymore? */
-	.rename = cifs_rename,
 	.permission = cifs_permission,
 #ifdef CONFIG_CIFS_XATTR
 	.setxattr = cifs_setxattr,
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 216d7e99f921..8807442c94dd 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -2579,19 +2579,32 @@ cifs_writev(struct kiocb *iocb, const struct iovec *iov,
 	struct cifsInodeInfo *cinode = CIFS_I(inode);
 	struct TCP_Server_Info *server = tlink_tcon(cfile->tlink)->ses->server;
 	ssize_t rc = -EACCES;
-	loff_t lock_pos = pos;
+	loff_t lock_pos = iocb->ki_pos;
 
-	if (file->f_flags & O_APPEND)
-		lock_pos = i_size_read(inode);
 	/*
 	 * We need to hold the sem to be sure nobody modifies lock list
 	 * with a brlock that prevents writing.
 	 */
 	down_read(&cinode->lock_sem);
+	mutex_lock(&inode->i_mutex);
+	if (file->f_flags & O_APPEND)
+		lock_pos = i_size_read(inode);
 	if (!cifs_find_lock_conflict(cfile, lock_pos, iov_length(iov, nr_segs),
 				     server->vals->exclusive_lock_type, NULL,
-				     CIFS_WRITE_OP))
-		rc = generic_file_aio_write(iocb, iov, nr_segs, pos);
+				     CIFS_WRITE_OP)) {
+		rc = __generic_file_aio_write(iocb, iov, nr_segs);
+		mutex_unlock(&inode->i_mutex);
+
+		if (rc > 0) {
+			ssize_t err;
+
+			err = generic_write_sync(file, iocb->ki_pos - rc, rc);
+			if (rc < 0)
+				rc = err;
+		}
+	} else {
+		mutex_unlock(&inode->i_mutex);
+	}
 	up_read(&cinode->lock_sem);
 	return rc;
 }
@@ -2727,56 +2740,27 @@ cifs_retry_async_readv(struct cifs_readdata *rdata)
 /**
  * cifs_readdata_to_iov - copy data from pages in response to an iovec
  * @rdata:	the readdata response with list of pages holding data
- * @iov:	vector in which we should copy the data
- * @nr_segs:	number of segments in vector
- * @offset:	offset into file of the first iovec
- * @copied:	used to return the amount of data copied to the iov
+ * @iter:	destination for our data
  *
  * This function copies data from a list of pages in a readdata response into
  * an array of iovecs. It will first calculate where the data should go
  * based on the info in the readdata and then copy the data into that spot.
  */
-static ssize_t
-cifs_readdata_to_iov(struct cifs_readdata *rdata, const struct iovec *iov,
-			unsigned long nr_segs, loff_t offset, ssize_t *copied)
+static int
+cifs_readdata_to_iov(struct cifs_readdata *rdata, struct iov_iter *iter)
 {
-	int rc = 0;
-	struct iov_iter ii;
-	size_t pos = rdata->offset - offset;
-	ssize_t remaining = rdata->bytes;
-	unsigned char *pdata;
+	size_t remaining = rdata->bytes;
 	unsigned int i;
 
-	/* set up iov_iter and advance to the correct offset */
-	iov_iter_init(&ii, iov, nr_segs, iov_length(iov, nr_segs), 0);
-	iov_iter_advance(&ii, pos);
-
-	*copied = 0;
 	for (i = 0; i < rdata->nr_pages; i++) {
-		ssize_t copy;
 		struct page *page = rdata->pages[i];
-
-		/* copy a whole page or whatever's left */
-		copy = min_t(ssize_t, remaining, PAGE_SIZE);
-
-		/* ...but limit it to whatever space is left in the iov */
-		copy = min_t(ssize_t, copy, iov_iter_count(&ii));
-
-		/* go while there's data to be copied and no errors */
-		if (copy && !rc) {
-			pdata = kmap(page);
-			rc = memcpy_toiovecend(ii.iov, pdata, ii.iov_offset,
-						(int)copy);
-			kunmap(page);
-			if (!rc) {
-				*copied += copy;
-				remaining -= copy;
-				iov_iter_advance(&ii, copy);
-			}
-		}
+		size_t copy = min(remaining, PAGE_SIZE);
+		size_t written = copy_page_to_iter(page, 0, copy, iter);
+		remaining -= written;
+		if (written < copy && iov_iter_count(iter) > 0)
+			break;
 	}
-
-	return rc;
+	return remaining ? -EFAULT : 0;
 }
 
 static void
@@ -2837,20 +2821,21 @@ cifs_uncached_read_into_pages(struct TCP_Server_Info *server,
 	return total_read > 0 ? total_read : result;
 }
 
-static ssize_t
-cifs_iovec_read(struct file *file, const struct iovec *iov,
-		 unsigned long nr_segs, loff_t *poffset)
+ssize_t cifs_user_readv(struct kiocb *iocb, const struct iovec *iov,
+			       unsigned long nr_segs, loff_t pos)
 {
+	struct file *file = iocb->ki_filp;
 	ssize_t rc;
 	size_t len, cur_len;
 	ssize_t total_read = 0;
-	loff_t offset = *poffset;
+	loff_t offset = pos;
 	unsigned int npages;
 	struct cifs_sb_info *cifs_sb;
 	struct cifs_tcon *tcon;
 	struct cifsFileInfo *open_file;
 	struct cifs_readdata *rdata, *tmp;
 	struct list_head rdata_list;
+	struct iov_iter to;
 	pid_t pid;
 
 	if (!nr_segs)
@@ -2860,6 +2845,8 @@ cifs_iovec_read(struct file *file, const struct iovec *iov,
 	if (!len)
 		return 0;
 
+	iov_iter_init(&to, iov, nr_segs, len, 0);
+
 	INIT_LIST_HEAD(&rdata_list);
 	cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
 	open_file = file->private_data;
@@ -2917,55 +2904,44 @@ error:
 	if (!list_empty(&rdata_list))
 		rc = 0;
 
+	len = iov_iter_count(&to);
 	/* the loop below should proceed in the order of increasing offsets */
-restart_loop:
 	list_for_each_entry_safe(rdata, tmp, &rdata_list, list) {
+	again:
 		if (!rc) {
-			ssize_t copied;
-
 			/* FIXME: freezable sleep too? */
 			rc = wait_for_completion_killable(&rdata->done);
 			if (rc)
 				rc = -EINTR;
-			else if (rdata->result)
+			else if (rdata->result) {
 				rc = rdata->result;
-			else {
-				rc = cifs_readdata_to_iov(rdata, iov,
-							nr_segs, *poffset,
-							&copied);
-				total_read += copied;
+				/* resend call if it's a retryable error */
+				if (rc == -EAGAIN) {
+					rc = cifs_retry_async_readv(rdata);
+					goto again;
+				}
+			} else {
+				rc = cifs_readdata_to_iov(rdata, &to);
 			}
 
-			/* resend call if it's a retryable error */
-			if (rc == -EAGAIN) {
-				rc = cifs_retry_async_readv(rdata);
-				goto restart_loop;
-			}
 		}
 		list_del_init(&rdata->list);
 		kref_put(&rdata->refcount, cifs_uncached_readdata_release);
 	}
 
+	total_read = len - iov_iter_count(&to);
+
 	cifs_stats_bytes_read(tcon, total_read);
-	*poffset += total_read;
 
 	/* mask nodata case */
 	if (rc == -ENODATA)
 		rc = 0;
 
-	return total_read ? total_read : rc;
-}
-
-ssize_t cifs_user_readv(struct kiocb *iocb, const struct iovec *iov,
-			       unsigned long nr_segs, loff_t pos)
-{
-	ssize_t read;
-
-	read = cifs_iovec_read(iocb->ki_filp, iov, nr_segs, &pos);
-	if (read > 0)
-		iocb->ki_pos = pos;
-
-	return read;
+	if (total_read) {
+		iocb->ki_pos = pos + total_read;
+		return total_read;
+	}
+	return rc;
 }
 
 ssize_t
diff --git a/fs/exec.c b/fs/exec.c
index 9e81c630dfa7..476f3ebf437e 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -813,7 +813,7 @@ EXPORT_SYMBOL(kernel_read);
 
 ssize_t read_code(struct file *file, unsigned long addr, loff_t pos, size_t len)
 {
-	ssize_t res = file->f_op->read(file, (void __user *)addr, len, &pos);
+	ssize_t res = vfs_read(file, (void __user *)addr, len, &pos);
 	if (res > 0)
 		flush_icache_range(addr, addr + len);
 	return res;
diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index 4e508fc83dcf..ca7502d89fde 100644
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -146,7 +146,7 @@ ext4_file_dio_write(struct kiocb *iocb, const struct iovec *iov,
 			overwrite = 1;
 	}
 
-	ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos);
+	ret = __generic_file_aio_write(iocb, iov, nr_segs);
 	mutex_unlock(&inode->i_mutex);
 
 	if (ret > 0) {
diff --git a/fs/file.c b/fs/file.c
index b61293badfb1..8f294cfac697 100644
--- a/fs/file.c
+++ b/fs/file.c
@@ -25,7 +25,10 @@
 
 int sysctl_nr_open __read_mostly = 1024*1024;
 int sysctl_nr_open_min = BITS_PER_LONG;
-int sysctl_nr_open_max = 1024 * 1024; /* raised later */
+/* our max() is unusable in constant expressions ;-/ */
+#define __const_max(x, y) ((x) < (y) ? (x) : (y))
+int sysctl_nr_open_max = __const_max(INT_MAX, ~(size_t)0/sizeof(void *)) &
+			 -BITS_PER_LONG;
 
 static void *alloc_fdmem(size_t size)
 {
@@ -429,12 +432,6 @@ void exit_files(struct task_struct *tsk)
 	}
 }
 
-void __init files_defer_init(void)
-{
-	sysctl_nr_open_max = min((size_t)INT_MAX, ~(size_t)0/sizeof(void *)) &
-			     -BITS_PER_LONG;
-}
-
 struct files_struct init_files = {
 	.count		= ATOMIC_INIT(1),
 	.fdt		= &init_files.fdtab,
diff --git a/fs/file_table.c b/fs/file_table.c
index 01071c4d752e..a374f5033e97 100644
--- a/fs/file_table.c
+++ b/fs/file_table.c
@@ -52,7 +52,6 @@ static void file_free_rcu(struct rcu_head *head)
 static inline void file_free(struct file *f)
 {
 	percpu_counter_dec(&nr_files);
-	file_check_state(f);
 	call_rcu(&f->f_u.fu_rcuhead, file_free_rcu);
 }
 
@@ -178,47 +177,12 @@ struct file *alloc_file(struct path *path, fmode_t mode,
 	file->f_mapping = path->dentry->d_inode->i_mapping;
 	file->f_mode = mode;
 	file->f_op = fop;
-
-	/*
-	 * These mounts don't really matter in practice
-	 * for r/o bind mounts.  They aren't userspace-
-	 * visible.  We do this for consistency, and so
-	 * that we can do debugging checks at __fput()
-	 */
-	if ((mode & FMODE_WRITE) && !special_file(path->dentry->d_inode->i_mode)) {
-		file_take_write(file);
-		WARN_ON(mnt_clone_write(path->mnt));
-	}
 	if ((mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ)
 		i_readcount_inc(path->dentry->d_inode);
 	return file;
 }
 EXPORT_SYMBOL(alloc_file);
 
-/**
- * drop_file_write_access - give up ability to write to a file
- * @file: the file to which we will stop writing
- *
- * This is a central place which will give up the ability
- * to write to @file, along with access to write through
- * its vfsmount.
- */
-static void drop_file_write_access(struct file *file)
-{
-	struct vfsmount *mnt = file->f_path.mnt;
-	struct dentry *dentry = file->f_path.dentry;
-	struct inode *inode = dentry->d_inode;
-
-	put_write_access(inode);
-
-	if (special_file(inode->i_mode))
-		return;
-	if (file_check_writeable(file) != 0)
-		return;
-	__mnt_drop_write(mnt);
-	file_release_write(file);
-}
-
 /* the real guts of fput() - releasing the last reference to file
  */
 static void __fput(struct file *file)
@@ -253,8 +217,10 @@ static void __fput(struct file *file)
 	put_pid(file->f_owner.pid);
 	if ((file->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ)
 		i_readcount_dec(inode);
-	if (file->f_mode & FMODE_WRITE)
-		drop_file_write_access(file);
+	if (file->f_mode & FMODE_WRITER) {
+		put_write_access(inode);
+		__mnt_drop_write(mnt);
+	}
 	file->f_path.dentry = NULL;
 	file->f_path.mnt = NULL;
 	file->f_inode = NULL;
@@ -359,6 +325,5 @@ void __init files_init(unsigned long mempages)
 
 	n = (mempages * (PAGE_SIZE / 1024)) / 10;
 	files_stat.max_files = max_t(unsigned long, n, NR_FILE);
-	files_defer_init();
 	percpu_counter_init(&nr_files, 0);
 } 
diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index 0a648bb455ae..aac71ce373e4 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -667,15 +667,15 @@ static void fuse_copy_finish(struct fuse_copy_state *cs)
 		struct pipe_buffer *buf = cs->currbuf;
 
 		if (!cs->write) {
-			buf->ops->unmap(cs->pipe, buf, cs->mapaddr);
+			kunmap_atomic(cs->mapaddr);
 		} else {
-			kunmap(buf->page);
+			kunmap_atomic(cs->mapaddr);
 			buf->len = PAGE_SIZE - cs->len;
 		}
 		cs->currbuf = NULL;
 		cs->mapaddr = NULL;
 	} else if (cs->mapaddr) {
-		kunmap(cs->pg);
+		kunmap_atomic(cs->mapaddr);
 		if (cs->write) {
 			flush_dcache_page(cs->pg);
 			set_page_dirty_lock(cs->pg);
@@ -706,7 +706,7 @@ static int fuse_copy_fill(struct fuse_copy_state *cs)
 
 			BUG_ON(!cs->nr_segs);
 			cs->currbuf = buf;
-			cs->mapaddr = buf->ops->map(cs->pipe, buf, 0);
+			cs->mapaddr = kmap_atomic(buf->page);
 			cs->len = buf->len;
 			cs->buf = cs->mapaddr + buf->offset;
 			cs->pipebufs++;
@@ -726,7 +726,7 @@ static int fuse_copy_fill(struct fuse_copy_state *cs)
 			buf->len = 0;
 
 			cs->currbuf = buf;
-			cs->mapaddr = kmap(page);
+			cs->mapaddr = kmap_atomic(page);
 			cs->buf = cs->mapaddr;
 			cs->len = PAGE_SIZE;
 			cs->pipebufs++;
@@ -745,7 +745,7 @@ static int fuse_copy_fill(struct fuse_copy_state *cs)
 			return err;
 		BUG_ON(err != 1);
 		offset = cs->addr % PAGE_SIZE;
-		cs->mapaddr = kmap(cs->pg);
+		cs->mapaddr = kmap_atomic(cs->pg);
 		cs->buf = cs->mapaddr + offset;
 		cs->len = min(PAGE_SIZE - offset, cs->seglen);
 		cs->seglen -= cs->len;
@@ -874,7 +874,7 @@ static int fuse_try_move_page(struct fuse_copy_state *cs, struct page **pagep)
 out_fallback_unlock:
 	unlock_page(newpage);
 out_fallback:
-	cs->mapaddr = buf->ops->map(cs->pipe, buf, 1);
+	cs->mapaddr = kmap_atomic(buf->page);
 	cs->buf = cs->mapaddr + buf->offset;
 
 	err = lock_request(cs->fc, cs->req);
diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index 48992cac714b..13f8bdec5110 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -1086,9 +1086,7 @@ static ssize_t fuse_fill_write_pages(struct fuse_req *req,
 		if (mapping_writably_mapped(mapping))
 			flush_dcache_page(page);
 
-		pagefault_disable();
 		tmp = iov_iter_copy_from_user_atomic(page, ii, offset, bytes);
-		pagefault_enable();
 		flush_dcache_page(page);
 
 		mark_page_accessed(page);
@@ -1237,8 +1235,7 @@ static ssize_t fuse_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
 		goto out;
 
 	if (file->f_flags & O_DIRECT) {
-		written = generic_file_direct_write(iocb, iov, &nr_segs,
-						    pos, &iocb->ki_pos,
+		written = generic_file_direct_write(iocb, iov, &nr_segs, pos, 
 						    count, ocount);
 		if (written < 0 || written == count)
 			goto out;
diff --git a/fs/mount.h b/fs/mount.h
index b29e42f05f34..d55297f2fa05 100644
--- a/fs/mount.h
+++ b/fs/mount.h
@@ -10,7 +10,7 @@ struct mnt_namespace {
 	struct user_namespace	*user_ns;
 	u64			seq;	/* Sequence number to prevent loops */
 	wait_queue_head_t poll;
-	int event;
+	u64 event;
 };
 
 struct mnt_pcp {
@@ -104,6 +104,9 @@ struct proc_mounts {
 	struct mnt_namespace *ns;
 	struct path root;
 	int (*show)(struct seq_file *, struct vfsmount *);
+	void *cached_mount;
+	u64 cached_event;
+	loff_t cached_index;
 };
 
 #define proc_mounts(p) (container_of((p), struct proc_mounts, m))
diff --git a/fs/namei.c b/fs/namei.c
index 88339f59efb5..c6157c894fce 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -358,6 +358,7 @@ int generic_permission(struct inode *inode, int mask)
 
 	return -EACCES;
 }
+EXPORT_SYMBOL(generic_permission);
 
 /*
  * We _really_ want to just do "generic_permission()" without
@@ -455,6 +456,7 @@ int inode_permission(struct inode *inode, int mask)
 		return retval;
 	return __inode_permission(inode, mask);
 }
+EXPORT_SYMBOL(inode_permission);
 
 /**
  * path_get - get a reference to a path
@@ -924,6 +926,7 @@ int follow_up(struct path *path)
 	path->mnt = &parent->mnt;
 	return 1;
 }
+EXPORT_SYMBOL(follow_up);
 
 /*
  * Perform an automount
@@ -1085,6 +1088,7 @@ int follow_down_one(struct path *path)
 	}
 	return 0;
 }
+EXPORT_SYMBOL(follow_down_one);
 
 static inline bool managed_dentry_might_block(struct dentry *dentry)
 {
@@ -1223,6 +1227,7 @@ int follow_down(struct path *path)
 	}
 	return 0;
 }
+EXPORT_SYMBOL(follow_down);
 
 /*
  * Skip to top of mountpoint pile in refwalk mode for follow_dotdot()
@@ -2025,6 +2030,7 @@ int kern_path(const char *name, unsigned int flags, struct path *path)
 		*path = nd.path;
 	return res;
 }
+EXPORT_SYMBOL(kern_path);
 
 /