Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755064AbbLYWLq (ORCPT ); Fri, 25 Dec 2015 17:11:46 -0500 Received: from g9t5009.houston.hp.com ([15.240.92.67]:48270 "EHLO g9t5009.houston.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754473AbbLYWKb (ORCPT ); Fri, 25 Dec 2015 17:10:31 -0500 From: Toshi Kani To: akpm@linux-foundation.org, bp@alien8.de Cc: linux-arch@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Dan Williams , Toshi Kani Subject: [PATCH v2 13/16] resource: Add walk_iomem_res_desc() Date: Fri, 25 Dec 2015 15:09:22 -0700 Message-Id: <1451081365-15190-13-git-send-email-toshi.kani@hpe.com> X-Mailer: git-send-email 2.4.3 In-Reply-To: <1451081365-15190-1-git-send-email-toshi.kani@hpe.com> References: <1451081365-15190-1-git-send-email-toshi.kani@hpe.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5693 Lines: 148 Add a new interface, walk_iomem_res_desc(), which walks through the iomem table by identifying a target with @flags and @desc. This interface provides the same functionality as walk_iomem_res(), but does not use strcmp() to @name for better efficiency. walk_iomem_res() is deprecated, but is maintained for backward compatibility since walk_iomem_res_desc() requires 'desc' of a target resource entry be initialized with its descriptor ID. Cc: Andrew Morton Cc: Borislav Petkov Cc: Dan Williams Signed-off-by: Toshi Kani --- include/linux/ioport.h | 3 ++ kernel/resource.c | 58 ++++++++++++++++++++++++++++++++++++++++++------ 2 files changed, 54 insertions(+), 7 deletions(-) diff --git a/include/linux/ioport.h b/include/linux/ioport.h index b7350c0..c4cd43a 100644 --- a/include/linux/ioport.h +++ b/include/linux/ioport.h @@ -269,6 +269,9 @@ extern int walk_system_ram_res(u64 start, u64 end, void *arg, int (*func)(u64, u64, void *)); extern int +walk_iomem_res_desc(unsigned long desc, unsigned long flags, u64 start, u64 end, + void *arg, int (*func)(u64, u64, void *)); +extern int walk_iomem_res(char *name, unsigned long flags, u64 start, u64 end, void *arg, int (*func)(u64, u64, void *)); diff --git a/kernel/resource.c b/kernel/resource.c index 52e6380..579b0e1 100644 --- a/kernel/resource.c +++ b/kernel/resource.c @@ -334,13 +334,14 @@ 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. + * the caller must specify res->start, res->end, res->flags, and optionally + * desc 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. */ -static int find_next_iomem_res(struct resource *res, char *name, - bool first_level_children_only) +static int find_next_iomem_res(struct resource *res, unsigned long desc, + char *name, bool first_level_children_only) { resource_size_t start, end; struct resource *p; @@ -360,6 +361,8 @@ static int find_next_iomem_res(struct resource *res, char *name, for (p = iomem_resource.child; p; p = next_resource(p, sibling_only)) { if ((p->flags & res->flags) != res->flags) continue; + if ((desc != IORES_DESC_NONE) && (desc != p->desc)) + continue; if (name && strcmp(p->name, name)) continue; if (p->start > end) { @@ -387,10 +390,51 @@ static int find_next_iomem_res(struct resource *res, char *name, * All the memory ranges which overlap start,end and also match flags and * name are valid candidates. * + * @desc: I/O resource descriptor. Use IORES_DESC_NONE to skip this check. + * @flags: I/O resource flags + * @start: start addr + * @end: end addr + * + * NOTE: For a new descriptor search, define a new IORES_DESC in + * and set it to 'desc' of a target resource entry. + */ +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; + int ret = -1; + + res.start = start; + res.end = end; + res.flags = flags; + orig_end = res.end; + + while ((res.start < res.end) && + (!find_next_iomem_res(&res, desc, NULL, false))) { + ret = (*func)(res.start, res.end, arg); + if (ret) + break; + res.start = res.end + 1; + res.end = orig_end; + } + + return ret; +} + +/* + * 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. + * * @name: name of resource * @flags: resource flags * @start: start addr * @end: end addr + * + * NOTE: This function is deprecated and should not be used in new code. + * Use walk_iomem_res_desc(), instead. */ int walk_iomem_res(char *name, unsigned long flags, u64 start, u64 end, void *arg, int (*func)(u64, u64, void *)) @@ -404,7 +448,7 @@ int walk_iomem_res(char *name, unsigned long flags, u64 start, u64 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, IORES_DESC_NONE, name, false))) { ret = (*func)(res.start, res.end, arg); if (ret) break; @@ -433,7 +477,7 @@ int walk_system_ram_res(u64 start, u64 end, void *arg, res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; orig_end = res.end; while ((res.start < res.end) && - (!find_next_iomem_res(&res, NULL, true))) { + (!find_next_iomem_res(&res, IORES_DESC_NONE, NULL, true))) { ret = (*func)(res.start, res.end, arg); if (ret) break; @@ -463,7 +507,7 @@ int walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages, res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; orig_end = res.end; while ((res.start < res.end) && - (find_next_iomem_res(&res, NULL, true) >= 0)) { + (find_next_iomem_res(&res, IORES_DESC_NONE, NULL, true) >= 0)) { pfn = (res.start + PAGE_SIZE - 1) >> PAGE_SHIFT; end_pfn = (res.end + 1) >> PAGE_SHIFT; if (end_pfn > pfn) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/