[XFS] use scalable vmap API

Implement XFS's large buffer support with the new vmap APIs. See the vmap
rewrite (db64fe02) for some numbers. The biggest improvement that comes from
using the new APIs is avoiding the global KVA allocation lock on every call.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Reviewed-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

diff --git a/fs/xfs/linux-2.6/xfs_buf.c b/fs/xfs/linux-2.6/xfs_buf.c
index 0b2177a9fbdcfc5677c9b9937f050c5e6c0060b0..d71dc44e21edbe7077bda8d35f9b259aac61522d 100644 (file)
--- a/fs/xfs/linux-2.6/xfs_buf.c
+++ b/fs/xfs/linux-2.6/xfs_buf.c
@@ -264,7 +264,7 @@ xfs_buf_free(
                uint            i;
 
                if ((bp->b_flags & XBF_MAPPED) && (bp->b_page_count > 1))
-                       vunmap(bp->b_addr - bp->b_offset);
+                       vm_unmap_ram(bp->b_addr - bp->b_offset, bp->b_page_count);
 
                for (i = 0; i < bp->b_page_count; i++) {
                        struct page     *page = bp->b_pages[i];
@@ -386,8 +386,8 @@ _xfs_buf_map_pages(
                bp->b_addr = page_address(bp->b_pages[0]) + bp->b_offset;
                bp->b_flags |= XBF_MAPPED;
        } else if (flags & XBF_MAPPED) {
-               bp->b_addr = vmap(bp->b_pages, bp->b_page_count,
-                                       VM_MAP, PAGE_KERNEL);
+               bp->b_addr = vm_map_ram(bp->b_pages, bp->b_page_count,
+                                       -1, PAGE_KERNEL);
                if (unlikely(bp->b_addr == NULL))
                        return -ENOMEM;
                bp->b_addr += bp->b_offset;