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

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  mm: export generic_pipe_buf_*() to modules
  fuse: support splice() reading from fuse device
  fuse: allow splice to move pages
  mm: export remove_from_page_cache() to modules
  mm: export lru_cache_add_*() to modules
  fuse: support splice() writing to fuse device
  fuse: get page reference for readpages
  fuse: use get_user_pages_fast()
  fuse: remove unneeded variable

1 files changed, 24 insertions, 15 deletions

diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index b5fd6f9905e4..ada0adeb3bb5 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -516,17 +516,26 @@ static void fuse_readpages_end(struct fuse_conn *fc, struct fuse_req *req)
         int i;
         size_t count = req->misc.read.in.size;
         size_t num_read = req->out.args[0].size;
-        struct inode *inode = req->pages[0]->mapping->host;
+        struct address_space *mapping = NULL;
 
-        /*
-         * Short read means EOF.  If file size is larger, truncate it
-         */
-        if (!req->out.h.error && num_read < count) {
-                loff_t pos = page_offset(req->pages[0]) + num_read;
-                fuse_read_update_size(inode, pos, req->misc.read.attr_ver);
-        }
+        for (i = 0; mapping == NULL && i < req->num_pages; i++)
+                mapping = req->pages[i]->mapping;
 
-        fuse_invalidate_attr(inode); /* atime changed */
+        if (mapping) {
+                struct inode *inode = mapping->host;
+
+                /*
+                 * Short read means EOF. If file size is larger, truncate it
+                 */
+                if (!req->out.h.error && num_read < count) {
+                        loff_t pos;
+
+                        pos = page_offset(req->pages[0]) + num_read;
+                        fuse_read_update_size(inode, pos,
+                                              req->misc.read.attr_ver);
+                }
+                fuse_invalidate_attr(inode); /* atime changed */
+        }
 
         for (i = 0; i < req->num_pages; i++) {
                 struct page *page = req->pages[i];
@@ -535,6 +544,7 @@ static void fuse_readpages_end(struct fuse_conn *fc, struct fuse_req *req)
                 else
                         SetPageError(page);
                 unlock_page(page);
+                page_cache_release(page);
         }
         if (req->ff)
                 fuse_file_put(req->ff);
@@ -549,6 +559,7 @@ static void fuse_send_readpages(struct fuse_req *req, struct file *file)
 
         req->out.argpages = 1;
         req->out.page_zeroing = 1;
+        req->out.page_replace = 1;
         fuse_read_fill(req, file, pos, count, FUSE_READ);
         req->misc.read.attr_ver = fuse_get_attr_version(fc);
         if (fc->async_read) {
@@ -588,6 +599,7 @@ static int fuse_readpages_fill(void *_data, struct page *page)
                         return PTR_ERR(req);
                 }
         }
+        page_cache_get(page);
         req->pages[req->num_pages] = page;
         req->num_pages++;
         return 0;
@@ -993,10 +1005,7 @@ static int fuse_get_user_pages(struct fuse_req *req, const char __user *buf,
         nbytes = min_t(size_t, nbytes, FUSE_MAX_PAGES_PER_REQ << PAGE_SHIFT);
         npages = (nbytes + offset + PAGE_SIZE - 1) >> PAGE_SHIFT;
         npages = clamp(npages, 1, FUSE_MAX_PAGES_PER_REQ);
-        down_read(&current->mm->mmap_sem);
-        npages = get_user_pages(current, current->mm, user_addr, npages, !write,
-                                0, req->pages, NULL);
-        up_read(&current->mm->mmap_sem);
+        npages = get_user_pages_fast(user_addr, npages, !write, req->pages);
         if (npages < 0)
                 return npages;
 
@@ -1579,9 +1588,9 @@ static int fuse_ioctl_copy_user(struct page **pages, struct iovec *iov,
         while (iov_iter_count(&ii)) {
                 struct page *page = pages[page_idx++];
                 size_t todo = min_t(size_t, PAGE_SIZE, iov_iter_count(&ii));
-                void *kaddr, *map;
+                void *kaddr;
 
-                kaddr = map = kmap(page);
+                kaddr = kmap(page);
 
                 while (todo) {
                         char __user *uaddr = ii.iov->iov_base + ii.iov_offset;