From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1N5KGG-0004ZN-4n for qemu-devel@nongnu.org; Tue, 03 Nov 2009 09:21:28 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1N5KGA-0004Rb-HF for qemu-devel@nongnu.org; Tue, 03 Nov 2009 09:21:27 -0500 Received: from [199.232.76.173] (port=44065 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1N5KGA-0004RB-Af for qemu-devel@nongnu.org; Tue, 03 Nov 2009 09:21:22 -0500 Received: from mx1.redhat.com ([209.132.183.28]:45688) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1N5KG9-0007Qk-Qs for qemu-devel@nongnu.org; Tue, 03 Nov 2009 09:21:22 -0500 Date: Tue, 3 Nov 2009 16:18:48 +0200 From: "Michael S. Tsirkin" Message-ID: <20091103141848.GD5605@redhat.com> References: <1256905286-25435-1-git-send-email-yamahata@valinux.co.jp> <1256905286-25435-26-git-send-email-yamahata@valinux.co.jp> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1256905286-25435-26-git-send-email-yamahata@valinux.co.jp> Subject: [Qemu-devel] Re: [PATCH V6 25/32] pci: add helper functions to check ranges overlap. List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Isaku Yamahata Cc: qemu-devel@nongnu.org On Fri, Oct 30, 2009 at 09:21:19PM +0900, Isaku Yamahata wrote: > add helper function to check ranges overlap suggested by > Michael S. Tsirkin . > His original suggestion was to use [first, last], however I chosen > to use offset, length pair, i.e. [offset, offset + length) > because pci configuration space related functions all uses offset and length > pair, so it helps to avoid to type constant twice. > > Cc: Michael S. Tsirkin > Signed-off-by: Isaku Yamahata Acked-by: Michael S. Tsirkin > --- > hw/pci.h | 29 +++++++++++++++++++++++++++++ > 1 files changed, 29 insertions(+), 0 deletions(-) > > diff --git a/hw/pci.h b/hw/pci.h > index 8e5d64a..7991bfd 100644 > --- a/hw/pci.h > +++ b/hw/pci.h > @@ -406,4 +406,33 @@ PCIBus *pci_apb_init(target_phys_addr_t special_base, > PCIBus *sh_pci_register_bus(pci_set_irq_fn set_irq, pci_map_irq_fn map_irq, > void *pic, int devfn_min, int nirq); > > +/* These are not pci specific. Should move into a separate header. > + * Only pci.c uses them, so keep them here for now. > + */ > + > +/* Get last byte of a range from offset + length. > + * Undefined for ranges that wrap around 0. */ > +static inline uint64_t range_get_last(uint64_t offset, uint64_t len) > +{ > + return offset + len - 1; > +} > + > +/* Check whether a given range covers a given byte. */ > +static inline int range_covers_byte(uint64_t offset, uint64_t len, > + uint64_t byte) > +{ > + return offset <= byte && byte <= range_get_last(offset, len); > +} > + > +/* Check whether 2 given ranges overlap. > + * Undefined if ranges that wrap around 0. */ > +static inline int ranges_overlap(uint64_t first1, uint64_t len1, > + uint64_t first2, uint64_t len2) > +{ > + uint64_t last1 = range_get_last(first1, len1); > + uint64_t last2 = range_get_last(first2, len2); > + > + return !(last2 < first1 || last1 < first2); > +} > + > #endif > -- > 1.6.0.2