Date: Tue, 21 May 2013 16:34:45 +0000 (UTC) From: Attilio Rao <attilio@FreeBSD.org> To: src-committers@freebsd.org, svn-src-user@freebsd.org Subject: svn commit: r250858 - user/attilio/vmobj-readlock/sys/kern Message-ID: <201305211634.r4LGYj4x063532@svn.freebsd.org>
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Author: attilio Date: Tue May 21 16:34:44 2013 New Revision: 250858 URL: http://svnweb.freebsd.org/changeset/base/250858 Log: o Relax assert in vfs_buf_test_cache() (even if it is unlikely to be exploited, it is more fair). o Use read-locking in vfs_bio_bzero_buf() because it should be fine to do so. Sponsored by: EMC / Isilon storage division Modified: user/attilio/vmobj-readlock/sys/kern/vfs_bio.c Modified: user/attilio/vmobj-readlock/sys/kern/vfs_bio.c ============================================================================== --- user/attilio/vmobj-readlock/sys/kern/vfs_bio.c Tue May 21 15:48:35 2013 (r250857) +++ user/attilio/vmobj-readlock/sys/kern/vfs_bio.c Tue May 21 16:34:44 2013 (r250858) @@ -478,7 +478,7 @@ vfs_buf_test_cache(struct buf *bp, vm_page_t m) { - VM_OBJECT_ASSERT_WLOCKED(m->object); + VM_OBJECT_ASSERT_LOCKED(m->object); if (bp->b_flags & B_CACHE) { int base = (foff + off) & PAGE_MASK; if (vm_page_is_valid(m, base, size) == 0) @@ -4215,7 +4215,7 @@ vfs_bio_bzero_buf(struct buf *bp, int ba } else { BUF_CHECK_UNMAPPED(bp); n = PAGE_SIZE - (base & PAGE_MASK); - VM_OBJECT_WLOCK(bp->b_bufobj->bo_object); + VM_OBJECT_RLOCK(bp->b_bufobj->bo_object); for (i = base / PAGE_SIZE; size > 0 && i < bp->b_npages; ++i) { m = bp->b_pages[i]; if (n > size) @@ -4225,7 +4225,7 @@ vfs_bio_bzero_buf(struct buf *bp, int ba size -= n; n = PAGE_SIZE; } - VM_OBJECT_WUNLOCK(bp->b_bufobj->bo_object); + VM_OBJECT_RUNLOCK(bp->b_bufobj->bo_object); } }
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