2 files changed, 104 insertions, 83 deletions

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 1a57c17d4029..a53aca338c7f 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -2017,6 +2017,7 @@ static int __extent_read_full_page(struct extent_io_tree *tree,
         sector_t sector;
         struct extent_map *em;
         struct block_device *bdev;
+        struct btrfs_ordered_extent *ordered;
         int ret;
         int nr = 0;
         size_t page_offset = 0;
@@ -2028,7 +2029,15 @@ static int __extent_read_full_page(struct extent_io_tree *tree,
         set_page_extent_mapped(page);
 
         end = page_end;
-        lock_extent(tree, start, end, GFP_NOFS);
+        while (1) {
+                lock_extent(tree, start, end, GFP_NOFS);
+                ordered = btrfs_lookup_ordered_extent(inode, start);
+                if (!ordered)
+                        break;
+                unlock_extent(tree, start, end, GFP_NOFS);
+                btrfs_start_ordered_extent(inode, ordered, 1);
+                btrfs_put_ordered_extent(ordered);
+        }
 
         if (page->index == last_byte >> PAGE_CACHE_SHIFT) {
                 char *userpage;
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index a28810abfb98..233aea2e5ef2 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -46,32 +46,42 @@
 static noinline int btrfs_copy_from_user(loff_t pos, int num_pages,
                                          int write_bytes,
                                          struct page **prepared_pages,
-                                         const char __user *buf)
+                                         struct iov_iter *i)
 {
-        long page_fault = 0;
-        int i;
+        size_t copied;
+        int pg = 0;
         int offset = pos & (PAGE_CACHE_SIZE - 1);
 
-        for (i = 0; i < num_pages && write_bytes > 0; i++, offset = 0) {
+        while (write_bytes > 0) {
                 size_t count = min_t(size_t,
                                      PAGE_CACHE_SIZE - offset, write_bytes);
-                struct page *page = prepared_pages[i];
-                fault_in_pages_readable(buf, count);
+                struct page *page = prepared_pages[pg];
+again:
+                if (unlikely(iov_iter_fault_in_readable(i, count)))
+                        return -EFAULT;
 
                 /* Copy data from userspace to the current page */
-                kmap(page);
-                page_fault = __copy_from_user(page_address(page) + offset,
-                                              buf, count);
+                copied = iov_iter_copy_from_user(page, i, offset, count);
+
                 /* Flush processor's dcache for this page */
                 flush_dcache_page(page);
-                kunmap(page);
-                buf += count;
-                write_bytes -= count;
+                iov_iter_advance(i, copied);
+                write_bytes -= copied;
 
-                if (page_fault)
-                        break;
+                if (unlikely(copied == 0)) {
+                        count = min_t(size_t, PAGE_CACHE_SIZE - offset,
+                                      iov_iter_single_seg_count(i));
+                        goto again;
+                }
+
+                if (unlikely(copied < PAGE_CACHE_SIZE - offset)) {
+                        offset += copied;
+                } else {
+                        pg++;
+                        offset = 0;
+                }
         }
-        return page_fault ? -EFAULT : 0;
+        return 0;
 }
 
 /*
@@ -822,60 +832,24 @@ again:
         return 0;
 }
 
-/* Copied from read-write.c */
-static void wait_on_retry_sync_kiocb(struct kiocb *iocb)
-{
-        set_current_state(TASK_UNINTERRUPTIBLE);
-        if (!kiocbIsKicked(iocb))
-                schedule();
-        else
-                kiocbClearKicked(iocb);
-        __set_current_state(TASK_RUNNING);
-}
-
-/*
- * Just a copy of what do_sync_write does.
- */
-static ssize_t __btrfs_direct_write(struct file *file, const char __user *buf,
-                                    size_t count, loff_t pos, loff_t *ppos)
+static ssize_t btrfs_file_aio_write(struct kiocb *iocb,
+                                    const struct iovec *iov,
+                                    unsigned long nr_segs, loff_t pos)
 {
-        struct iovec iov = { .iov_base = (void __user *)buf, .iov_len = count };
-        unsigned long nr_segs = 1;
-        struct kiocb kiocb;
-        ssize_t ret;
-
-        init_sync_kiocb(&kiocb, file);
-        kiocb.ki_pos = pos;
-        kiocb.ki_left = count;
-        kiocb.ki_nbytes = count;
-
-        while (1) {
-                ret = generic_file_direct_write(&kiocb, &iov, &nr_segs, pos,
-                                                ppos, count, count);
-                if (ret != -EIOCBRETRY)
-                        break;
-                wait_on_retry_sync_kiocb(&kiocb);
-        }
-
-        if (ret == -EIOCBQUEUED)
-                ret = wait_on_sync_kiocb(&kiocb);
-        *ppos = kiocb.ki_pos;
-        return ret;
-}
-
-static ssize_t btrfs_file_write(struct file *file, const char __user *buf,
-                                size_t count, loff_t *ppos)
-{
-        loff_t pos;
+        struct file *file = iocb->ki_filp;
+        struct inode *inode = fdentry(file)->d_inode;
+        struct btrfs_root *root = BTRFS_I(inode)->root;
+        struct page *pinned[2];
+        struct page **pages = NULL;
+        struct iov_iter i;
+        loff_t *ppos = &iocb->ki_pos;
         loff_t start_pos;
         ssize_t num_written = 0;
         ssize_t err = 0;
+        size_t count;
+        size_t ocount;
         int ret = 0;
-        struct inode *inode = fdentry(file)->d_inode;
-        struct btrfs_root *root = BTRFS_I(inode)->root;
-        struct page **pages = NULL;
         int nrptrs;
-        struct page *pinned[2];
         unsigned long first_index;
         unsigned long last_index;
         int will_write;
@@ -887,13 +861,17 @@ static ssize_t btrfs_file_write(struct file *file, const char __user *buf,
         pinned[0] = NULL;
         pinned[1] = NULL;
 
-        pos = *ppos;
         start_pos = pos;
 
         vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE);
 
         mutex_lock(&inode->i_mutex);
 
+        err = generic_segment_checks(iov, &nr_segs, &ocount, VERIFY_READ);
+        if (err)
+                goto out;
+        count = ocount;
+
         current->backing_dev_info = inode->i_mapping->backing_dev_info;
         err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
         if (err)
@@ -910,14 +888,48 @@ static ssize_t btrfs_file_write(struct file *file, const char __user *buf,
         BTRFS_I(inode)->sequence++;
 
         if (unlikely(file->f_flags & O_DIRECT)) {
-                num_written = __btrfs_direct_write(file, buf, count, pos,
-                                                   ppos);
-                pos += num_written;
-                count -= num_written;
+                ret = btrfs_delalloc_reserve_space(inode, count);
+                if (ret)
+                        goto out;