GFS2: Make write size hinting code common

[deliverable/linux.git] / fs / gfs2 / file.c

diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c
index 9aa6af13823c5b75d3e8d2723d281dc79cee7a47..382000ffac1f7e892163665a27982e587b9d83e7 100644 (file)
--- a/fs/gfs2/file.c
+++ b/fs/gfs2/file.c
@@ -322,6 +322,29 @@ static long gfs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
        return -ENOTTY;
 }
 
+/**
+ * gfs2_size_hint - Give a hint to the size of a write request
+ * @file: The struct file
+ * @offset: The file offset of the write
+ * @size: The length of the write
+ *
+ * When we are about to do a write, this function records the total
+ * write size in order to provide a suitable hint to the lower layers
+ * about how many blocks will be required.
+ *
+ */
+
+static void gfs2_size_hint(struct file *filep, loff_t offset, size_t size)
+{
+       struct inode *inode = filep->f_dentry->d_inode;
+       struct gfs2_sbd *sdp = GFS2_SB(inode);
+       struct gfs2_inode *ip = GFS2_I(inode);
+       size_t blks = (size + sdp->sd_sb.sb_bsize - 1) >> sdp->sd_sb.sb_bsize_shift;
+       int hint = min_t(size_t, INT_MAX, blks);
+
+       atomic_set(&ip->i_res->rs_sizehint, hint);
+}
+
 /**
  * gfs2_allocate_page_backing - Use bmap to allocate blocks
  * @page: The (locked) page to allocate backing for
@@ -373,18 +396,16 @@ static int gfs2_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
        loff_t size;
        int ret;
 
-       /* Wait if fs is frozen. This is racy so we check again later on
-        * and retry if the fs has been frozen after the page lock has
-        * been acquired
-        */
-       vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE);
+       sb_start_pagefault(inode->i_sb);
+
+       /* Update file times before taking page lock */
+       file_update_time(vma->vm_file);
 
        ret = gfs2_rs_alloc(ip);
        if (ret)
                return ret;
 
-       atomic_set(&ip->i_res->rs_sizehint,
-                  PAGE_CACHE_SIZE >> sdp->sd_sb.sb_bsize_shift);
+       gfs2_size_hint(vma->vm_file, pos, PAGE_CACHE_SIZE);
 
        gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
        ret = gfs2_glock_nq(&gh);
@@ -462,14 +483,9 @@ out:
        gfs2_holder_uninit(&gh);
        if (ret == 0) {
                set_page_dirty(page);
-               /* This check must be post dropping of transaction lock */
-               if (inode->i_sb->s_frozen == SB_UNFROZEN) {
-                       wait_on_page_writeback(page);
-               } else {
-                       ret = -EAGAIN;
-                       unlock_page(page);
-               }
+               wait_on_page_writeback(page);
        }
+       sb_end_pagefault(inode->i_sb);
        return block_page_mkwrite_return(ret);
 }
 
@@ -669,7 +685,8 @@ static ssize_t gfs2_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
        if (ret)
                return ret;
 
-       atomic_set(&ip->i_res->rs_sizehint, writesize >> sdp->sd_sb.sb_bsize_shift);
+       gfs2_size_hint(file, pos, writesize);
+
        if (file->f_flags & O_APPEND) {
                struct gfs2_holder gh;
 
@@ -795,7 +812,7 @@ static long gfs2_fallocate(struct file *file, int mode, loff_t offset,
        if (unlikely(error))
                goto out_uninit;
 
-       atomic_set(&ip->i_res->rs_sizehint, len >> sdp->sd_sb.sb_bsize_shift);
+       gfs2_size_hint(file, offset, len);
 
        while (len > 0) {
                if (len < bytes)