summaryrefslogtreecommitdiffstats
path: root/kernel/fs/ntfs/aops.h
diff options
context:
space:
mode:
authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/fs/ntfs/aops.h
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/fs/ntfs/aops.h')
-rw-r--r--kernel/fs/ntfs/aops.h107
1 files changed, 107 insertions, 0 deletions
diff --git a/kernel/fs/ntfs/aops.h b/kernel/fs/ntfs/aops.h
new file mode 100644
index 000000000..caecc58f5
--- /dev/null
+++ b/kernel/fs/ntfs/aops.h
@@ -0,0 +1,107 @@
+/**
+ * aops.h - Defines for NTFS kernel address space operations and page cache
+ * handling. Part of the Linux-NTFS project.
+ *
+ * Copyright (c) 2001-2004 Anton Altaparmakov
+ * Copyright (c) 2002 Richard Russon
+ *
+ * This program/include file is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program/include file is distributed in the hope that it will be
+ * useful, but WITHOUT ANY WARRANTY; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program (in the main directory of the Linux-NTFS
+ * distribution in the file COPYING); if not, write to the Free Software
+ * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#ifndef _LINUX_NTFS_AOPS_H
+#define _LINUX_NTFS_AOPS_H
+
+#include <linux/mm.h>
+#include <linux/highmem.h>
+#include <linux/pagemap.h>
+#include <linux/fs.h>
+
+#include "inode.h"
+
+/**
+ * ntfs_unmap_page - release a page that was mapped using ntfs_map_page()
+ * @page: the page to release
+ *
+ * Unpin, unmap and release a page that was obtained from ntfs_map_page().
+ */
+static inline void ntfs_unmap_page(struct page *page)
+{
+ kunmap(page);
+ page_cache_release(page);
+}
+
+/**
+ * ntfs_map_page - map a page into accessible memory, reading it if necessary
+ * @mapping: address space for which to obtain the page
+ * @index: index into the page cache for @mapping of the page to map
+ *
+ * Read a page from the page cache of the address space @mapping at position
+ * @index, where @index is in units of PAGE_CACHE_SIZE, and not in bytes.
+ *
+ * If the page is not in memory it is loaded from disk first using the readpage
+ * method defined in the address space operations of @mapping and the page is
+ * added to the page cache of @mapping in the process.
+ *
+ * If the page belongs to an mst protected attribute and it is marked as such
+ * in its ntfs inode (NInoMstProtected()) the mst fixups are applied but no
+ * error checking is performed. This means the caller has to verify whether
+ * the ntfs record(s) contained in the page are valid or not using one of the
+ * ntfs_is_XXXX_record{,p}() macros, where XXXX is the record type you are
+ * expecting to see. (For details of the macros, see fs/ntfs/layout.h.)
+ *
+ * If the page is in high memory it is mapped into memory directly addressible
+ * by the kernel.
+ *
+ * Finally the page count is incremented, thus pinning the page into place.
+ *
+ * The above means that page_address(page) can be used on all pages obtained
+ * with ntfs_map_page() to get the kernel virtual address of the page.
+ *
+ * When finished with the page, the caller has to call ntfs_unmap_page() to
+ * unpin, unmap and release the page.
+ *
+ * Note this does not grant exclusive access. If such is desired, the caller
+ * must provide it independently of the ntfs_{un}map_page() calls by using
+ * a {rw_}semaphore or other means of serialization. A spin lock cannot be
+ * used as ntfs_map_page() can block.
+ *
+ * The unlocked and uptodate page is returned on success or an encoded error
+ * on failure. Caller has to test for error using the IS_ERR() macro on the
+ * return value. If that evaluates to 'true', the negative error code can be
+ * obtained using PTR_ERR() on the return value of ntfs_map_page().
+ */
+static inline struct page *ntfs_map_page(struct address_space *mapping,
+ unsigned long index)
+{
+ struct page *page = read_mapping_page(mapping, index, NULL);
+
+ if (!IS_ERR(page)) {
+ kmap(page);
+ if (!PageError(page))
+ return page;
+ ntfs_unmap_page(page);
+ return ERR_PTR(-EIO);
+ }
+ return page;
+}
+
+#ifdef NTFS_RW
+
+extern void mark_ntfs_record_dirty(struct page *page, const unsigned int ofs);
+
+#endif /* NTFS_RW */
+
+#endif /* _LINUX_NTFS_AOPS_H */