Merge branch 'akpm' (patches from Andrew)

Merge third patchbomb from Andrew Morton:

 - various misc things

 - a couple of lib/ optimisations

 - provide DIV_ROUND_CLOSEST_ULL()

 - checkpatch updates

 - rtc tree

 - befs, nilfs2, hfs, hfsplus, fatfs, adfs, affs, bfs

 - ptrace fixes

 - fork() fixes

 - seccomp cleanups

 - more mmap_sem hold time reductions from Davidlohr

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (138 commits)
  proc: show locks in /proc/pid/fdinfo/X
  docs: add missing and new /proc/PID/status file entries, fix typos
  drivers/rtc/rtc-at91rm9200.c: make IO endian agnostic
  Documentation/spi/spidev_test.c: fix warning
  drivers/rtc/rtc-s5m.c: allow usage on device type different than main MFD type
  .gitignore: ignore *.tar
  MAINTAINERS: add Mediatek SoC mailing list
  tomoyo: reduce mmap_sem hold for mm->exe_file
  powerpc/oprofile: reduce mmap_sem hold for exe_file
  oprofile: reduce mmap_sem hold for mm->exe_file
  mips: ip32: add platform data hooks to use DS1685 driver
  lib/Kconfig: fix up HAVE_ARCH_BITREVERSE help text
  x86: switch to using asm-generic for seccomp.h
  sparc: switch to using asm-generic for seccomp.h
  powerpc: switch to using asm-generic for seccomp.h
  parisc: switch to using asm-generic for seccomp.h
  mips: switch to using asm-generic for seccomp.h
  microblaze: use asm-generic for seccomp.h
  arm: use asm-generic for seccomp.h
  seccomp: allow COMPAT sigreturn overrides
  ...

1 files changed, 54 insertions, 0 deletions

diff --git a/fs/nilfs2/mdt.c b/fs/nilfs2/mdt.c
index 892cf5ffdb8e..dee34d990281 100644
--- a/fs/nilfs2/mdt.c
+++ b/fs/nilfs2/mdt.c
@@ -261,6 +261,60 @@ int nilfs_mdt_get_block(struct inode *inode, unsigned long blkoff, int create,
 }
 
 /**
+ * nilfs_mdt_find_block - find and get a buffer on meta data file.
+ * @inode: inode of the meta data file
+ * @start: start block offset (inclusive)
+ * @end: end block offset (inclusive)
+ * @blkoff: block offset
+ * @out_bh: place to store a pointer to buffer_head struct
+ *
+ * nilfs_mdt_find_block() looks up an existing block in range of
+ * [@start, @end] and stores pointer to a buffer head of the block to
+ * @out_bh, and block offset to @blkoff, respectively.  @out_bh and
+ * @blkoff are substituted only when zero is returned.
+ *
+ * Return Value: On success, it returns 0. On error, the following negative
+ * error code is returned.
+ *
+ * %-ENOMEM - Insufficient memory available.
+ *
+ * %-EIO - I/O error
+ *
+ * %-ENOENT - no block was found in the range
+ */
+int nilfs_mdt_find_block(struct inode *inode, unsigned long start,
+			 unsigned long end, unsigned long *blkoff,
+			 struct buffer_head **out_bh)
+{
+	__u64 next;
+	int ret;
+
+	if (unlikely(start > end))
+		return -ENOENT;
+
+	ret = nilfs_mdt_read_block(inode, start, true, out_bh);
+	if (!ret) {
+		*blkoff = start;
+		goto out;
+	}
+	if (unlikely(ret != -ENOENT || start == ULONG_MAX))
+		goto out;
+
+	ret = nilfs_bmap_seek_key(NILFS_I(inode)->i_bmap, start + 1, &next);
+	if (!ret) {
+		if (next <= end) {
+			ret = nilfs_mdt_read_block(inode, next, true, out_bh);
+			if (!ret)
+				*blkoff = next;
+		} else {
+			ret = -ENOENT;
+		}
+	}
+out:
+	return ret;
+}
+
+/**
  * nilfs_mdt_delete_block - make a hole on the meta data file.
  * @inode: inode of the meta data file
  * @block: block offset