Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753720AbXLGO6y (ORCPT ); Fri, 7 Dec 2007 09:58:54 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756345AbXLGO5n (ORCPT ); Fri, 7 Dec 2007 09:57:43 -0500 Received: from mo11.iij4u.or.jp ([210.138.174.79]:53678 "EHLO mo11.iij4u.or.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756316AbXLGO5k (ORCPT ); Fri, 7 Dec 2007 09:57:40 -0500 Date: Fri, 7 Dec 2007 23:56:39 +0900 To: linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org Cc: akpm@linux-foundation.org, tglx@linutronix.de, mingo@elte.hu, muli@il.ibm.com, benh@kernel.crashing.org, paulus@samba.org, olof@lixom.net, anton@samba.org Cc: fujita.tomonori@lab.ntt.co.jp Subject: [PATCH -mm 1/6] add IOMMU helper functions for the free area management From: FUJITA Tomonori In-Reply-To: <21710c4b9cd6848e70e29949dfb54894e9aabbe6.tomof@acm.org> References: <21710c4b9cd6848e70e29949dfb54894e9aabbe6.tomof@acm.org> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-Id: <20071207235649E.tomof@acm.org> X-Dispatcher: imput version 20040704(IM147) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3653 Lines: 124 This adds IOMMU helper functions for the free area management. These functions take care of LLD's segment boundary limit for IOMMUs. They would be useful for IOMMUs that use bitmap for the free area management. Signed-off-by: FUJITA Tomonori --- include/linux/iommu-helper.h | 7 ++++ lib/Makefile | 1 + lib/iommu-helper.c | 76 ++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 84 insertions(+), 0 deletions(-) create mode 100644 include/linux/iommu-helper.h create mode 100644 lib/iommu-helper.c diff --git a/include/linux/iommu-helper.h b/include/linux/iommu-helper.h new file mode 100644 index 0000000..4dd4c04 --- /dev/null +++ b/include/linux/iommu-helper.h @@ -0,0 +1,7 @@ +extern unsigned long iommu_area_alloc(unsigned long *map, unsigned long size, + unsigned long start, unsigned int nr, + unsigned long shift, + unsigned long boundary_size, + unsigned long align_mask); +extern void iommu_area_free(unsigned long *map, unsigned long start, + unsigned int nr); diff --git a/lib/Makefile b/lib/Makefile index b862b90..17fb758 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -65,6 +65,7 @@ obj-$(CONFIG_SMP) += pcounter.o obj-$(CONFIG_AUDIT_GENERIC) += audit.o obj-$(CONFIG_SWIOTLB) += swiotlb.o +obj-$(CONFIG_IOMMU_HELPER) += iommu-helper.o obj-$(CONFIG_FAULT_INJECTION) += fault-inject.o lib-$(CONFIG_GENERIC_BUG) += bug.o diff --git a/lib/iommu-helper.c b/lib/iommu-helper.c new file mode 100644 index 0000000..e7d8544 --- /dev/null +++ b/lib/iommu-helper.c @@ -0,0 +1,76 @@ +/* + * IOMMU helper functions for the free area management + */ + +#include +#include + +static unsigned long find_next_zero_area(unsigned long *map, + unsigned long size, + unsigned long start, + unsigned int nr) +{ + unsigned long index, end, i; +again: + index = find_next_zero_bit(map, size, start); + end = index + nr; + if (end > size) + return -1; + for (i = index + 1; i < end; i++) { + if (test_bit(i, map)) { + start = i+1; + goto again; + } + } + return index; +} + +static inline void set_bit_area(unsigned long *map, unsigned long i, + int len) +{ + unsigned long end = i + len; + while (i < end) { + __set_bit(i, map); + i++; + } +} + +static inline int is_span_boundary(unsigned int index, unsigned int nr, + unsigned long shift, + unsigned long boundary_size) +{ + shift = (shift + index) & (boundary_size - 1); + return shift + nr > boundary_size; +} + +unsigned long iommu_area_alloc(unsigned long *map, unsigned long size, + unsigned long start, unsigned int nr, + unsigned long shift, unsigned long boundary_size, + unsigned long align_mask) +{ + unsigned long index; +again: + index = find_next_zero_area(map, size, start, nr); + if (index != -1) { + index = (index + align_mask) & ~align_mask; + if (is_span_boundary(index, nr, shift, boundary_size)) { + /* we could do more effectively */ + start = index + 1; + goto again; + } + set_bit_area(map, index, nr); + } + return index; +} +EXPORT_SYMBOL(iommu_area_alloc); + +void iommu_area_free(unsigned long *map, unsigned long start, unsigned int nr) +{ + unsigned long end = start + nr; + + while (start < end) { + __clear_bit(start, map); + start++; + } +} +EXPORT_SYMBOL(iommu_area_free); -- 1.5.3.4 -- 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/