Commit 11fa977e authored Jul 23, 2008 by Hugh Dickins Committed by Linus Torvalds Jul 24, 2008

generic_file_aio_read() cleanups



As akpm points out, there's really no need for generic_file_aio_read to
make a special case of count 0: just loop through nr_segs doing nothing.
And as Harvey Harrison points out, there's no need to reset retval to 0
where it's already 0.

Setting count (or ocount) to 0 before calling generic_segment_checks is
unnecessary too; but reluctantly I'll leave that removal to someone with a
wider range of gcc versions to hand - 4.1.2 and 4.2.1 don't warn about it,
but perhaps others do - I forget which are the warniest versions.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Tested-by: Lawrence Greenfield <leg@google.com>
Cc: Christoph Rohland <hans-christoph.rohland@sap.com>
Cc: Badari Pulavarty <pbadari@us.ibm.com>
Cc: Zach Brown <zach.brown@oracle.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent a858f7b2

mm/filemap.c

+19 −23

Original line number	Diff line number	Diff line
		@@ -1197,7 +1197,6 @@ generic_file_aio_read(struct kiocb iocb, const struct iovec iov,

		mapping = filp->f_mapping;
		inode = mapping->host;
		retval = 0;
		if (!count)
		goto out; /* skip atime */
		size = i_size_read(inode);
		@@ -1209,15 +1208,13 @@ generic_file_aio_read(struct kiocb iocb, const struct iovec iov,
		}
		if (retval > 0)
		*ppos = pos + retval;
		}
		if (likely(retval != 0)) {
		if (retval) {
		file_accessed(filp);
		goto out;
		}
		}
		}

		retval = 0;
		if (count) {
		for (seg = 0; seg < nr_segs; seg++) {
		read_descriptor_t desc;

		@@ -1236,7 +1233,6 @@ generic_file_aio_read(struct kiocb iocb, const struct iovec iov,
		if (desc.count > 0)
		break;
		}
		}
		out:
		return retval;
		}