From ff54250a0ebab7f90a5f848a0ba63f999830c872 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sat, 18 Apr 2009 21:44:24 -0700 Subject: [PATCH] Remove 'recurse into child resources' logic from 'reserve_region_with_split()' This function is not actually used right now, since the original use case for it was done with insert_resource_expand_to_fit() instead. However, we now have another usage case that wants to basically do a "reserve IO resource, splitting around existing resources", however that one doesn't actually want the "recurse into the conflicting resource" logic at all. And since recursing into the conflicting resource was the most complex part, and isn't wanted, just remove it. Maybe we'll some day want both versions, but we can just resurrect the logic then. Tested-by: Yinghai Lu Signed-off-by: Linus Torvalds --- kernel/resource.c | 46 ++++++++++++---------------------------------- 1 file changed, 12 insertions(+), 34 deletions(-) diff --git a/kernel/resource.c b/kernel/resource.c index fd5d7d574bb9..ac5f3a36923f 100644 --- a/kernel/resource.c +++ b/kernel/resource.c @@ -533,43 +533,21 @@ static void __init __reserve_region_with_split(struct resource *root, res->end = end; res->flags = IORESOURCE_BUSY; - for (;;) { - conflict = __request_resource(parent, res); - if (!conflict) - break; - if (conflict != parent) { - parent = conflict; - if (!(conflict->flags & IORESOURCE_BUSY)) - continue; - } + conflict = __request_resource(parent, res); + if (!conflict) + return; - /* Uhhuh, that didn't work out.. */ - kfree(res); - res = NULL; - break; - } + /* failed, split and try again */ + kfree(res); - if (!res) { - /* failed, split and try again */ - - /* conflict covered whole area */ - if (conflict->start <= start && conflict->end >= end) - return; - - if (conflict->start > start) - __reserve_region_with_split(root, start, conflict->start-1, name); - if (!(conflict->flags & IORESOURCE_BUSY)) { - resource_size_t common_start, common_end; - - common_start = max(conflict->start, start); - common_end = min(conflict->end, end); - if (common_start < common_end) - __reserve_region_with_split(root, common_start, common_end, name); - } - if (conflict->end < end) - __reserve_region_with_split(root, conflict->end+1, end, name); - } + /* conflict covered whole area */ + if (conflict->start <= start && conflict->end >= end) + return; + if (conflict->start > start) + __reserve_region_with_split(root, start, conflict->start-1, name); + if (conflict->end < end) + __reserve_region_with_split(root, conflict->end+1, end, name); } void __init reserve_region_with_split(struct resource *root,