1 files changed, 10 insertions, 147 deletions

diff --git a/fs/buffer.c b/fs/buffer.c
index 9a73924db22f..cabc045f483d 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -185,10 +185,9 @@ EXPORT_SYMBOL(end_buffer_write_sync);
  * we get exclusion from try_to_free_buffers with the blockdev mapping's
  * private_lock.
  *
- * Hack idea: for the blockdev mapping, i_bufferlist_lock contention
+ * Hack idea: for the blockdev mapping, private_lock contention
  * may be quite high.  This code could TryLock the page, and if that
- * succeeds, there is no need to take private_lock. (But if
- * private_lock is contended then so is mapping->tree_lock).
+ * succeeds, there is no need to take private_lock.
  */
 static struct buffer_head *
 __find_get_block_slow(struct block_device *bdev, sector_t block)
@@ -495,35 +494,12 @@ repeat:
         return err;
 }
 
-static void do_thaw_one(struct super_block *sb, void *unused)
+void emergency_thaw_bdev(struct super_block *sb)
 {
         while (sb->s_bdev && !thaw_bdev(sb->s_bdev, sb))
                 printk(KERN_WARNING "Emergency Thaw on %pg\n", sb->s_bdev);
 }
 
-static void do_thaw_all(struct work_struct *work)
-{
-        iterate_supers(do_thaw_one, NULL);
-        kfree(work);
-        printk(KERN_WARNING "Emergency Thaw complete\n");
-}
-
-/**
- * emergency_thaw_all -- forcibly thaw every frozen filesystem
- *
- * Used for emergency unfreeze of all filesystems via SysRq
- */
-void emergency_thaw_all(void)
-{
-        struct work_struct *work;
-
-        work = kmalloc(sizeof(*work), GFP_ATOMIC);
-        if (work) {
-                INIT_WORK(work, do_thaw_all);
-                schedule_work(work);
-        }
-}
-
 /**
  * sync_mapping_buffers - write out & wait upon a mapping's "associated" buffers
  * @mapping: the mapping which wants those buffers written
@@ -594,20 +570,21 @@ EXPORT_SYMBOL(mark_buffer_dirty_inode);
  *
  * The caller must hold lock_page_memcg().
  */
-static void __set_page_dirty(struct page *page, struct address_space *mapping,
+void __set_page_dirty(struct page *page, struct address_space *mapping,
                              int warn)
 {
         unsigned long flags;
 
-        spin_lock_irqsave(&mapping->tree_lock, flags);
+        xa_lock_irqsave(&mapping->i_pages, flags);
         if (page->mapping) {    /* Race with truncate? */
                 WARN_ON_ONCE(warn && !PageUptodate(page));
                 account_page_dirtied(page, mapping);
-                radix_tree_tag_set(&mapping->page_tree,
+                radix_tree_tag_set(&mapping->i_pages,
                                 page_index(page), PAGECACHE_TAG_DIRTY);
         }
-        spin_unlock_irqrestore(&mapping->tree_lock, flags);
+        xa_unlock_irqrestore(&mapping->i_pages, flags);
 }
+EXPORT_SYMBOL_GPL(__set_page_dirty);
 
 /*
  * Add a page to the dirty page list.
@@ -1095,7 +1072,7 @@ __getblk_slow(struct block_device *bdev, sector_t block,
  * inode list.
  *
  * mark_buffer_dirty() is atomic.  It takes bh->b_page->mapping->private_lock,
- * mapping->tree_lock and mapping->host->i_lock.
+ * i_pages lock and mapping->host->i_lock.
  */
 void mark_buffer_dirty(struct buffer_head *bh)
 {
@@ -1511,7 +1488,7 @@ void block_invalidatepage(struct page *page, unsigned int offset,
          * The get_block cached value has been unconditionally invalidated,
          * so real IO is not possible anymore.
          */
-        if (offset == 0)
+        if (length == PAGE_SIZE)
                 try_to_release_page(page, 0);
 out:
         return;
@@ -3450,120 +3427,6 @@ int bh_submit_read(struct buffer_head *bh)
 }
 EXPORT_SYMBOL(bh_submit_read);
 
-/*
- * Seek for SEEK_DATA / SEEK_HOLE within @page, starting at @lastoff.
- *
- * Returns the offset within the file on success, and -ENOENT otherwise.
- */
-static loff_t
-page_seek_hole_data(struct page *page, loff_t lastoff, int whence)
-{
-        loff_t offset = page_offset(page);
-        struct buffer_head *bh, *head;
-        bool seek_data = whence == SEEK_DATA;
-
-        if (lastoff < offset)
-                lastoff = offset;
-
-        bh = head = page_buffers(page);
-        do {
-                offset += bh->b_size;
-                if (lastoff >= offset)
-                        continue;
-
-                /*
-                 * Unwritten extents that have data in the page cache covering
-                 * them can be identified by the BH_Unwritten state flag.
-                 * Pages with multiple buffers might have a mix of holes, data
-                 * and unwritten extents - any buffer with valid data in it
-                 * should have BH_Uptodate flag set on it.
-                 */
-
-                if ((buffer_unwritten(bh) || buffer_uptodate(bh)) == seek_data)
-                        return lastoff;
-
-                lastoff = offset;
-        } while ((bh = bh->b_this_page) != head);
-        return -ENOENT;
-}
-
-/*
- * Seek for SEEK_DATA / SEEK_HOLE in the page cache.
- *
- * Within unwritten extents, the page cache determines which parts are holes
- * and which are data: unwritten and uptodate buffer heads count as data;
- * everything else counts as a hole.
- *
- * Returns the resulting offset on successs, and -ENOENT otherwise.
- */
-loff_t
-page_cache_seek_hole_data(struct inode *inode, loff_t offset, loff_t length,
-                          int whence)
-{
-        pgoff_t index = offset >> PAGE_SHIFT;
-        pgoff_t end = DIV_ROUND_UP(offset + length, PAGE_SIZE);
-        loff_t lastoff = offset;
-        struct pagevec pvec;
-
-        if (length <= 0)
-                return -ENOENT;
-
-        pagevec_init(&pvec);
-
-        do {
-                unsigned nr_pages, i;
-
-                nr_pages = pagevec_lookup_range(&pvec, inode->i_mapping, &index,
-                                                end - 1);
-                if (nr_pages == 0)
-                        break;
-
-                for (i = 0; i < nr_pages; i++) {
-                        struct page *page = pvec.pages[i];
-
-                        /*
-                         * At this point, the page may be truncated or
-                         * invalidated (changing page->mapping to NULL), or
-                         * even swizzled back from swapper_space to tmpfs file
-                         * mapping.  However, page->index will not change
-                         * because we have a reference on the page.
-                         *
-                         * If current page offset is beyond where we've ended,
-                         * we've found a hole.
-                         */
-                        if (whence == SEEK_HOLE &&
-                            lastoff < page_offset(page))
-                                goto check_range;
-
-                        lock_page(page);
-                        if (likely(page->mapping == inode->i_mapping) &&
-                            page_has_buffers(page)) {
-                                lastoff = page_seek_hole_data(page, lastoff, whence);
-                                if (lastoff >= 0) {
-                                        unlock_page(page);
-                                        goto check_range;
-                                }
-                        }
-                        unlock_page(page);
-                        lastoff = page_offset(page) + PAGE_SIZE;
-                }
-                pagevec_release(&pvec);
-        } while (index < end);
-
-        /* When no page at lastoff and we are not done, we found a hole. */
-        if (whence != SEEK_HOLE)
-                goto not_found;
-
-check_range:
-        if (lastoff < offset + length)
-                goto out;
-not_found:
-        lastoff = -ENOENT;
-out:
-        pagevec_release(&pvec);
-        return lastoff;
-}
-
 void __init buffer_init(void)
 {
         unsigned long nrpages;