diff options
Diffstat (limited to 'kernel/resource.c')
| -rw-r--r-- | kernel/resource.c | 38 |
1 files changed, 29 insertions, 9 deletions
diff --git a/kernel/resource.c b/kernel/resource.c index b3a3a1fc499e..e81b17b53fa5 100644 --- a/kernel/resource.c +++ b/kernel/resource.c @@ -319,16 +319,23 @@ int release_resource(struct resource *old) EXPORT_SYMBOL(release_resource); /** - * Finds the lowest iomem resource that covers part of [start..end]. The - * caller must specify start, end, flags, and desc (which may be + * 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. + * 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 or -EINVAL for other invalid parameters. * * This function walks the whole tree and not just first level children * unless @first_lvl is true. + * + * @start: start address of the resource searched for + * @end: end address of same resource + * @flags: flags which the resource must have + * @desc: descriptor the resource must have + * @first_lvl: walk only the first level children, if set + * @res: return ptr, if resource found */ static int find_next_iomem_res(resource_size_t start, resource_size_t end, unsigned long flags, unsigned long desc, @@ -399,6 +406,8 @@ static int __walk_iomem_res_desc(resource_size_t start, resource_size_t end, * @flags: I/O resource flags * @start: start addr * @end: end addr + * @arg: function argument for the callback @func + * @func: callback function that is called for each qualifying resource area * * NOTE: For a new descriptor search, define a new IORES_DESC in * <linux/ioport.h> and set it in 'desc' of a target resource entry. @@ -439,8 +448,6 @@ int walk_mem_res(u64 start, u64 end, void *arg, arg, func); } -#if !defined(CONFIG_ARCH_HAS_WALK_MEMORY) - /* * This function calls the @func callback against all memory ranges of type * System RAM which are marked as IORESOURCE_SYSTEM_RAM and IORESOUCE_BUSY. @@ -472,8 +479,6 @@ int walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages, return ret; } -#endif - static int __is_ram(unsigned long pfn, unsigned long nr_pages, void *arg) { return 1; @@ -1247,6 +1252,21 @@ int release_mem_region_adjustable(struct resource *parent, continue; } + /* + * All memory regions added from memory-hotplug path have the + * flag IORESOURCE_SYSTEM_RAM. If the resource does not have + * this flag, we know that we are dealing with a resource coming + * from HMM/devm. HMM/devm use another mechanism to add/release + * a resource. This goes via devm_request_mem_region and + * devm_release_mem_region. + * HMM/devm take care to release their resources when they want, + * so if we are dealing with them, let us just back off here. + */ + if (!(res->flags & IORESOURCE_SYSRAM)) { + ret = 0; + break; + } + if (!(res->flags & IORESOURCE_MEM)) break; |