diff options
Diffstat (limited to 'kernel/resource.c')
| -rw-r--r-- | kernel/resource.c | 149 |
1 files changed, 105 insertions, 44 deletions
diff --git a/kernel/resource.c b/kernel/resource.c index 3669d1bfc425..2e78ead30934 100644 --- a/kernel/resource.c +++ b/kernel/resource.c @@ -233,9 +233,9 @@ static struct resource * __request_resource(struct resource *root, struct resour } } -static int __release_resource(struct resource *old) +static int __release_resource(struct resource *old, bool release_child) { - struct resource *tmp, **p; + struct resource *tmp, **p, *chd; p = &old->parent->child; for (;;) { @@ -243,7 +243,17 @@ static int __release_resource(struct resource *old) if (!tmp) break; if (tmp == old) { - *p = tmp->sibling; + if (release_child || !(tmp->child)) { + *p = tmp->sibling; + } else { + for (chd = tmp->child;; chd = chd->sibling) { + chd->parent = tmp->parent; + if (!(chd->sibling)) + break; + } + *p = tmp->child; + chd->sibling = tmp->sibling; + } old->parent = NULL; return 0; } @@ -325,7 +335,7 @@ int release_resource(struct resource *old) int retval; write_lock(&resource_lock); - retval = __release_resource(old); + retval = __release_resource(old, true); write_unlock(&resource_lock); return retval; } @@ -333,13 +343,13 @@ int release_resource(struct resource *old) EXPORT_SYMBOL(release_resource); /* - * Finds the lowest iomem reosurce exists with-in [res->start.res->end) - * the caller must specify res->start, res->end, res->flags and "name". - * If found, returns 0, res is overwritten, if not found, returns -1. - * This walks through whole tree and not just first level children - * until and unless first_level_children_only is true. + * 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. */ -static int find_next_iomem_res(struct resource *res, char *name, +static int find_next_iomem_res(struct resource *res, unsigned long desc, bool first_level_children_only) { resource_size_t start, end; @@ -358,9 +368,9 @@ static int find_next_iomem_res(struct resource *res, char *name, read_lock(&resource_lock); for (p = iomem_resource.child; p; p = next_resource(p, sibling_only)) { - if (p->flags != res->flags) + if ((p->flags & res->flags) != res->flags) continue; - if (name && strcmp(p->name, name)) + if ((desc != IORES_DESC_NONE) && (desc != p->desc)) continue; if (p->start > end) { p = NULL; @@ -385,15 +395,18 @@ static int find_next_iomem_res(struct resource *res, char *name, * Walks through iomem resources and calls func() with matching resource * ranges. This walks through whole tree and not just first level children. * All the memory ranges which overlap start,end and also match flags and - * name are valid candidates. + * desc are valid candidates. * - * @name: name of resource - * @flags: resource flags + * @desc: I/O resource descriptor. Use IORES_DESC_NONE to skip @desc check. + * @flags: I/O resource flags * @start: start addr * @end: end addr + * + * 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. */ -int walk_iomem_res(char *name, unsigned long flags, u64 start, u64 end, - void *arg, int (*func)(u64, u64, void *)) +int walk_iomem_res_desc(unsigned long desc, unsigned long flags, u64 start, + u64 end, void *arg, int (*func)(u64, u64, void *)) { struct resource res; u64 orig_end; @@ -403,23 +416,27 @@ int walk_iomem_res(char *name, unsigned long flags, u64 start, u64 end, res.end = end; res.flags = flags; orig_end = res.end; + while ((res.start < res.end) && - (!find_next_iomem_res(&res, name, false))) { + (!find_next_iomem_res(&res, desc, false))) { + ret = (*func)(res.start, res.end, arg); if (ret) break; + res.start = res.end + 1; res.end = orig_end; } + return ret; } /* - * This function calls callback against all memory range of "System RAM" - * which are marked as IORESOURCE_MEM and IORESOUCE_BUSY. - * Now, this function is only for "System RAM". This function deals with - * full ranges and not pfn. If resources are not pfn aligned, dealing - * with pfn can truncate ranges. + * This function calls the @func callback against all memory ranges of type + * System RAM which are marked as IORESOURCE_SYSTEM_RAM and IORESOUCE_BUSY. + * Now, this function is only for System RAM, it deals with full ranges and + * not PFNs. If resources are not PFN-aligned, dealing with PFNs can truncate + * ranges. */ int walk_system_ram_res(u64 start, u64 end, void *arg, int (*func)(u64, u64, void *)) @@ -430,10 +447,10 @@ int walk_system_ram_res(u64 start, u64 end, void *arg, res.start = start; res.end = end; - res.flags = IORESOURCE_MEM | IORESOURCE_BUSY; + res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; orig_end = res.end; while ((res.start < res.end) && - (!find_next_iomem_res(&res, "System RAM", true))) { + (!find_next_iomem_res(&res, IORES_DESC_NONE, true))) { ret = (*func)(res.start, res.end, arg); if (ret) break; @@ -446,9 +463,9 @@ int walk_system_ram_res(u64 start, u64 end, void *arg, #if !defined(CONFIG_ARCH_HAS_WALK_MEMORY) /* - * This function calls callback against all memory range of "System RAM" - * which are marked as IORESOURCE_MEM and IORESOUCE_BUSY. - * Now, this function is only for "System RAM". + * This function calls the @func callback against all memory ranges of type + * System RAM which are marked as IORESOURCE_SYSTEM_RAM and IORESOUCE_BUSY. + * It is to be used only for System RAM. */ int walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages, void *arg, int (*func)(unsigned long, unsigned long, void *)) @@ -460,10 +477,10 @@ int walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages, res.start = (u64) start_pfn << PAGE_SHIFT; res.end = ((u64)(start_pfn + nr_pages) << PAGE_SHIFT) - 1; - res.flags = IORESOURCE_MEM | IORESOURCE_BUSY; + res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; orig_end = res.end; while ((res.start < res.end) && - (find_next_iomem_res(&res, "System RAM", true) >= 0)) { + (find_next_iomem_res(&res, IORES_DESC_NONE, true) >= 0)) { pfn = (res.start + PAGE_SIZE - 1) >> PAGE_SHIFT; end_pfn = (res.end + 1) >> PAGE_SHIFT; if (end_pfn > pfn) @@ -484,7 +501,7 @@ static int __is_ram(unsigned long pfn, unsigned long nr_pages, void *arg) } /* * This generic page_is_ram() returns true if specified address is - * registered as "System RAM" in iomem_resource list. + * registered as System RAM in iomem_resource list. */ int __weak page_is_ram(unsigned long pfn) { @@ -496,30 +513,34 @@ EXPORT_SYMBOL_GPL(page_is_ram); * region_intersects() - determine intersection of region with known resources * @start: region start address * @size: size of region - * @name: name of resource (in iomem_resource) + * @flags: flags of resource (in iomem_resource) + * @desc: descriptor of resource (in iomem_resource) or IORES_DESC_NONE * * Check if the specified region partially overlaps or fully eclipses a - * resource identified by @name. Return REGION_DISJOINT if the region - * does not overlap @name, return REGION_MIXED if the region overlaps - * @type and another resource, and return REGION_INTERSECTS if the - * region overlaps @type and no other defined resource. Note, that - * REGION_INTERSECTS is also returned in the case when the specified - * region overlaps RAM and undefined memory holes. + * resource identified by @flags and @desc (optional with IORES_DESC_NONE). + * Return REGION_DISJOINT if the region does not overlap @flags/@desc, + * return REGION_MIXED if the region overlaps @flags/@desc and another + * resource, and return REGION_INTERSECTS if the region overlaps @flags/@desc + * and no other defined resource. Note that REGION_INTERSECTS is also + * returned in the case when the specified region overlaps RAM and undefined + * memory holes. * * region_intersect() is used by memory remapping functions to ensure * the user is not remapping RAM and is a vast speed up over walking * through the resource table page by page. */ -int region_intersects(resource_size_t start, size_t size, const char *name) +int region_intersects(resource_size_t start, size_t size, unsigned long flags, + unsigned long desc) { - unsigned long flags = IORESOURCE_MEM | IORESOURCE_BUSY; resource_size_t end = start + size - 1; int type = 0; int other = 0; struct resource *p; read_lock(&resource_lock); for (p = iomem_resource.child; p ; p = p->sibling) { - bool is_type = strcmp(p->name, name) == 0 && p->flags == flags; + bool is_type = (((p->flags & flags) == flags) && + ((desc == IORES_DESC_NONE) || + (desc == p->desc))); if (start >= p->start && start <= p->end) is_type ? type++ : other++; @@ -538,6 +559,7 @@ int region_intersects(resource_size_t start, size_t size, const char *name) return REGION_DISJOINT; } +EXPORT_SYMBOL_GPL(region_intersects); void __weak arch_remove_reservations(struct resource *avail) { @@ -667,7 +689,7 @@ static int reallocate_resource(struct resource *root, struct resource *old, old->start = new.start; old->end = new.end; } else { - __release_resource(old); + __release_resource(old, true); *old = new; conflict = __request_resource(root, old); BUG_ON(conflict); @@ -813,6 +835,9 @@ static struct resource * __insert_resource(struct resource *parent, struct resou * entirely fit within the range of the new resource, then the new * resource is inserted and the conflicting resources become children of * the new resource. + * + * This function is intended for producers of resources, such as FW modules + * and bus drivers. */ struct resource *insert_resource_conflict(struct resource *parent, struct resource *new) { @@ -830,6 +855,9 @@ struct resource *insert_resource_conflict(struct resource *parent, struct resour * @new: new resource to insert * * Returns 0 on success, -EBUSY if the resource can't be inserted. + * + * This function is intended for producers of resources, such as FW modules + * and bus drivers. */ int insert_resource(struct resource *parent, struct resource *new) { @@ -838,6 +866,7 @@ int insert_resource(struct resource *parent, struct resource *new) conflict = insert_resource_conflict(parent, new); return conflict ? -EBUSY : 0; } +EXPORT_SYMBOL_GPL(insert_resource); /** * insert_resource_expand_to_fit - Insert a resource into the resource tree @@ -873,6 +902,32 @@ void insert_resource_expand_to_fit(struct resource *root, struct resource *new) write_unlock(&resource_lock); } +/** + * remove_resource - Remove a resource in the resource tree + * @old: resource to remove + * + * Returns 0 on success, -EINVAL if the resource is not valid. + * + * This function removes a resource previously inserted by insert_resource() + * or insert_resource_conflict(), and moves the children (if any) up to + * where they were before. insert_resource() and insert_resource_conflict() + * insert a new resource, and move any conflicting resources down to the + * children of the new resource. + * + * insert_resource(), insert_resource_conflict() and remove_resource() are + * intended for producers of resources, such as FW modules and bus drivers. + */ +int remove_resource(struct resource *old) +{ + int retval; + + write_lock(&resource_lock); + retval = __release_resource(old, false); + write_unlock(&resource_lock); + return retval; +} +EXPORT_SYMBOL_GPL(remove_resource); + static int __adjust_resource(struct resource *res, resource_size_t start, resource_size_t size) { @@ -948,6 +1003,7 @@ static void __init __reserve_region_with_split(struct resource *root, res->start = start; res->end = end; res->flags = IORESOURCE_BUSY; + res->desc = IORES_DESC_NONE; while (1) { @@ -982,6 +1038,7 @@ static void __init __reserve_region_with_split(struct resource *root, next_res->start = conflict->end + 1; next_res->end = end; next_res->flags = IORESOURCE_BUSY; + next_res->desc = IORES_DESC_NONE; } } else { res->start = conflict->end + 1; @@ -1071,14 +1128,16 @@ struct resource * __request_region(struct resource *parent, res->name = name; res->start = start; res->end = start + n - 1; - res->flags = resource_type(parent); - res->flags |= IORESOURCE_BUSY | flags; write_lock(&resource_lock); for (;;) { struct resource *conflict; + res->flags = resource_type(parent) | resource_ext_type(parent); + res->flags |= IORESOURCE_BUSY | flags; + res->desc = parent->desc; + conflict = __request_resource(parent, res); if (!conflict) break; @@ -1238,6 +1297,7 @@ int release_mem_region_adjustable(struct resource *parent, new_res->start = end + 1; new_res->end = res->end; new_res->flags = res->flags; + new_res->desc = res->desc; new_res->parent = res->parent; new_res->sibling = res->sibling; new_res->child = NULL; @@ -1413,6 +1473,7 @@ static int __init reserve_setup(char *str) res->start = io_start; res->end = io_start + io_num - 1; res->flags = IORESOURCE_BUSY; + res->desc = IORES_DESC_NONE; res->child = NULL; if (request_resource(res->start >= 0x10000 ? &iomem_resource : &ioport_resource, res) == 0) reserved = x+1; |