diff options
| -rw-r--r-- | sys/kern/subr_extent.c | 35 |
1 files changed, 26 insertions, 9 deletions
diff --git a/sys/kern/subr_extent.c b/sys/kern/subr_extent.c index 092d0c66c45..b36408e4ee0 100644 --- a/sys/kern/subr_extent.c +++ b/sys/kern/subr_extent.c @@ -1,4 +1,4 @@ -/* $OpenBSD: subr_extent.c,v 1.39 2009/06/09 19:16:39 oga Exp $ */ +/* $OpenBSD: subr_extent.c,v 1.40 2009/09/18 22:16:28 kettenis Exp $ */ /* $NetBSD: subr_extent.c,v 1.7 1996/11/21 18:46:34 cgd Exp $ */ /*- @@ -499,26 +499,43 @@ extent_alloc_region(struct extent *ex, u_long start, u_long size, int flags) */ if (flags & EX_CONFLICTOK) { /* - * There are two possibilities: + * There are four possibilities: * - * 1. The current region overlaps. + * 1. The current region overlaps with + * the start of the requested region. * Adjust the requested region to * start at the end of the current - * region, and try again. + * region and try again. * * 2. The current region falls - * completely within the requested - * region. Free the current region - * and try again. + * completely within the requested + * region. Free the current region + * and try again. + * + * 3. The current region overlaps with + * the end of the requested region. + * Adjust the requested region to + * end at the start of the current + * region and try again. + * + * 4. The requested region falls + * completely within the current + * region. We're done. */ if (rp->er_start <= start) { start = rp->er_end + 1; size = end - start + 1; - } else { + goto alloc_start; + } else if (rp->er_end < end) { LIST_REMOVE(rp, er_link); extent_free_region_descriptor(ex, rp); + goto alloc_start; + } else if (rp->er_start < end) { + end = rp->er_start - 1; + size = end - start + 1; + goto alloc_start; } - goto alloc_start; + return (0); } extent_free_region_descriptor(ex, myrp); |