diff options
| -rw-r--r-- | kernel/resource.c | 96 |
1 files changed, 42 insertions, 54 deletions
diff --git a/kernel/resource.c b/kernel/resource.c index 155ec873ea4d..38b8d11c9eaf 100644 --- a/kernel/resource.c +++ b/kernel/resource.c @@ -318,24 +318,27 @@ int release_resource(struct resource *old) EXPORT_SYMBOL(release_resource); -/* - * Finds the lowest iomem resource existing within [res->start..res->end]. - * The caller must specify res->start, res->end, res->flags, and optionally - * desc. If found, returns 0, res is overwritten, if not found, returns -1. - * This function walks the whole tree and not just first level children until - * and unless first_level_children_only is true. +/** + * Finds the lowest iomem resource that covers part of [start..end]. The + * caller must specify start, end, flags, and desc (which may be + * IORES_DESC_NONE). + * + * If a resource is found, returns 0 and *res is overwritten with the part + * of the resource that's within [start..end]; if none is found, returns + * -1. + * + * This function walks the whole tree and not just first level children + * unless @first_level_children_only is true. */ -static int find_next_iomem_res(struct resource *res, unsigned long desc, - bool first_level_children_only) +static int find_next_iomem_res(resource_size_t start, resource_size_t end, + unsigned long flags, unsigned long desc, + bool first_level_children_only, + struct resource *res) { - resource_size_t start, end; struct resource *p; bool sibling_only = false; BUG_ON(!res); - - start = res->start; - end = res->end; BUG_ON(start >= end); if (first_level_children_only) @@ -344,7 +347,7 @@ static int find_next_iomem_res(struct resource *res, unsigned long desc, read_lock(&resource_lock); for (p = iomem_resource.child; p; p = next_resource(p, sibling_only)) { - if ((p->flags & res->flags) != res->flags) + if ((p->flags & flags) != flags) continue; if ((desc != IORES_DESC_NONE) && (desc != p->desc)) continue; @@ -359,32 +362,31 @@ static int find_next_iomem_res(struct resource *res, unsigned long desc, read_unlock(&resource_lock); if (!p) return -1; + /* copy data */ - if (res->start < p->start) - res->start = p->start; - if (res->end > p->end) - res->end = p->end; + res->start = max(start, p->start); + res->end = min(end, p->end); res->flags = p->flags; res->desc = p->desc; return 0; } -static int __walk_iomem_res_desc(struct resource *res, unsigned long desc, - bool first_level_children_only, - void *arg, +static int __walk_iomem_res_desc(resource_size_t start, resource_size_t end, + unsigned long flags, unsigned long desc, + bool first_level_children_only, void *arg, int (*func)(struct resource *, void *)) { - u64 orig_end = res->end; + struct resource res; int ret = -1; - while ((res->start < res->end) && - !find_next_iomem_res(res, desc, first_level_children_only)) { - ret = (*func)(res, arg); + while (start < end && + !find_next_iomem_res(start, end, flags, desc, + first_level_children_only, &res)) { + ret = (*func)(&res, arg); if (ret) break; - res->start = res->end + 1; - res->end = orig_end; + start = res.end + 1; } return ret; @@ -407,13 +409,7 @@ static int __walk_iomem_res_desc(struct resource *res, unsigned long desc, int walk_iomem_res_desc(unsigned long desc, unsigned long flags, u64 start, u64 end, void *arg, int (*func)(struct resource *, void *)) { - struct resource res; - - res.start = start; - res.end = end; - res.flags = flags; - - return __walk_iomem_res_desc(&res, desc, false, arg, func); + return __walk_iomem_res_desc(start, end, flags, desc, false, arg, func); } EXPORT_SYMBOL_GPL(walk_iomem_res_desc); @@ -427,13 +423,9 @@ EXPORT_SYMBOL_GPL(walk_iomem_res_desc); int walk_system_ram_res(u64 start, u64 end, void *arg, int (*func)(struct resource *, void *)) { - struct resource res; + unsigned long flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; - res.start = start; - res.end = end; - res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; - - return __walk_iomem_res_desc(&res, IORES_DESC_NONE, true, + return __walk_iomem_res_desc(start, end, flags, IORES_DESC_NONE, true, arg, func); } @@ -444,13 +436,9 @@ int walk_system_ram_res(u64 start, u64 end, void *arg, int walk_mem_res(u64 start, u64 end, void *arg, int (*func)(struct resource *, void *)) { - struct resource res; + unsigned long flags = IORESOURCE_MEM | IORESOURCE_BUSY; - res.start = start; - res.end = end; - res.flags = IORESOURCE_MEM | IORESOURCE_BUSY; - - return __walk_iomem_res_desc(&res, IORES_DESC_NONE, true, + return __walk_iomem_res_desc(start, end, flags, IORES_DESC_NONE, true, arg, func); } @@ -464,25 +452,25 @@ int walk_mem_res(u64 start, u64 end, void *arg, int walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages, void *arg, int (*func)(unsigned long, unsigned long, void *)) { + resource_size_t start, end; + unsigned long flags; struct resource res; unsigned long pfn, end_pfn; - u64 orig_end; int ret = -1; - res.start = (u64) start_pfn << PAGE_SHIFT; - res.end = ((u64)(start_pfn + nr_pages) << PAGE_SHIFT) - 1; - res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; - orig_end = res.end; - while ((res.start < res.end) && - (find_next_iomem_res(&res, IORES_DESC_NONE, true) >= 0)) { + start = (u64) start_pfn << PAGE_SHIFT; + end = ((u64)(start_pfn + nr_pages) << PAGE_SHIFT) - 1; + flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; + while (start < end && + !find_next_iomem_res(start, end, flags, IORES_DESC_NONE, + true, &res)) { pfn = (res.start + PAGE_SIZE - 1) >> PAGE_SHIFT; end_pfn = (res.end + 1) >> PAGE_SHIFT; if (end_pfn > pfn) ret = (*func)(pfn, end_pfn - pfn, arg); if (ret) break; - res.start = res.end + 1; - res.end = orig_end; + start = res.end + 1; } return ret; } |