From patchwork Mon Oct 7 04:03:16 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Damien Le Moal X-Patchwork-Id: 13824007 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 901853C2F for ; Mon, 7 Oct 2024 04:03:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728273811; cv=none; b=GjdxxkIg7A5zlrh1wi/vgjC0jolPl5RfkM7nePIIXNrQzyVylNTNji0bieSmTWHx6YHOR37443enf6UqKXrV1pIxAoDkSjqXroCndDOiwdIwUYEx9dw1royYJq4caIsMqN3U4BkaLrHShmgwxd2nux7F6X5ctER2alM+Yuh6/FI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728273811; c=relaxed/simple; bh=KOlzri2s1hJeQueXMQVc7/f1GBi2mQLHYnXMS6K4sb8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=JcD+tAFD44+UlzfnbKfdq7wfZCluXwAPtGO9yEGDbvcA0I5MEV993pj2Hrqz2qIpL6WPvsAAJDhbO5akRIiHPaLkRV1hSIyoyl/6wJE/Ssm/HoIPY7FberMpsSYAUoijXdUcZyhrSO1NG3zvKyavB4ddElJGifBS2jcNVNaeZkE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=eaWrsK45; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="eaWrsK45" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D1372C4CED4; Mon, 7 Oct 2024 04:03:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1728273811; bh=KOlzri2s1hJeQueXMQVc7/f1GBi2mQLHYnXMS6K4sb8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=eaWrsK45aZB0oP7egIxQlvGoj4+JyowvmL9hGmPst9hbhUy0FnnlZsHBf2DyXX2vD TQjRRsttbMenZ8Br7RUNcGRIdNPcFzjcozu8hlP/sY1ST784BF1jwvSds5zexwA2Jj gMe0uYNnXTt2xUhBnUOSCSLKMus1KFbCJfscO9lyNUa86hJuKueZyxNSuh8d7Ybi4a rqSYOtY/43OkbqQqeVIpLGQ2NweX9BotLjblY5SdIQKek/qWBnBVf6e+nx/NyQyOzN Vml3iR2B8ovEQ9M0//VqGLn2+J8Wf1l6wrZ08Tl5LarrNHNmxvzK/SnBtpKFKKh3er +gETinZIhq2kA== From: Damien Le Moal To: Manivannan Sadhasivam , =?utf-8?q?Krzy?= =?utf-8?q?sztof_Wilczy=C5=84ski?= , Kishon Vijay Abraham I , Bjorn Helgaas , Lorenzo Pieralisi , Rob Herring , Jonathan Corbet , Jingoo Han , linux-pci@vger.kernel.org Cc: Rick Wertenbroek , Niklas Cassel Subject: [PATCH v4 4/7] PCI: endpoint: Introduce pci_epc_mem_map()/unmap() Date: Mon, 7 Oct 2024 13:03:16 +0900 Message-ID: <20241007040319.157412-5-dlemoal@kernel.org> X-Mailer: git-send-email 2.46.2 In-Reply-To: <20241007040319.157412-1-dlemoal@kernel.org> References: <20241007040319.157412-1-dlemoal@kernel.org> Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Introduce the function pci_epc_mem_map() to facilitate controller memory address allocation and mapping to a RC PCI address region in endpoint function drivers. This function first uses pci_epc_map_align() to determine the controller memory address size (and offset into) depending on the controller address alignment constraints. The result of this function is used to allocate a controller physical memory region using pci_epc_mem_alloc_addr() and map that memory to the RC PCI address space with pci_epc_map_addr(). Since pci_epc_map_align() may indicate that the effective mapping of a PCI address region is smaller than the user requested size, pci_epc_mem_map() may only partially map the RC PCI address region specified. It is the responsibility of the caller (an endpoint function driver) to handle such smaller mapping. The counterpart of pci_epc_mem_map() to unmap and free the controller memory address region is pci_epc_mem_unmap(). Both functions operate using a struct pci_epc_map data structure Endpoint function drivers can use struct pci_epc_map to access the mapped RC PCI address region using the ->virt_addr and ->pci_size fields. Co-developed-by: Rick Wertenbroek Signed-off-by: Rick Wertenbroek Signed-off-by: Damien Le Moal Reviewed-by: Niklas Cassel --- drivers/pci/endpoint/pci-epc-core.c | 78 +++++++++++++++++++++++++++++ include/linux/pci-epc.h | 4 ++ 2 files changed, 82 insertions(+) diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c index 1adccf07c33e..d03c753d0a53 100644 --- a/drivers/pci/endpoint/pci-epc-core.c +++ b/drivers/pci/endpoint/pci-epc-core.c @@ -532,6 +532,84 @@ int pci_epc_map_addr(struct pci_epc *epc, u8 func_no, u8 vfunc_no, } EXPORT_SYMBOL_GPL(pci_epc_map_addr); +/** + * pci_epc_mem_map() - allocate and map a PCI address to a CPU address + * @epc: the EPC device on which the CPU address is to be allocated and mapped + * @func_no: the physical endpoint function number in the EPC device + * @vfunc_no: the virtual endpoint function number in the physical function + * @pci_addr: PCI address to which the CPU address should be mapped + * @pci_size: the number of bytes to map starting from @pci_addr + * @map: where to return the mapping information + * + * Allocate a controller memory address region and map it to a RC PCI address + * region, taking into account the controller physical address mapping + * constraints using pci_epc_map_align(). + * The effective size of the PCI address range mapped from @pci_addr is + * indicated by @map->pci_size. This size may be less than the requested + * @pci_size. The local virtual CPU address for the mapping is indicated by + * @map->virt_addr (@map->phys_addr indicates the physical address). + * The size and CPU address of the controller memory allocated and mapped are + * respectively indicated by @map->map_size and @map->virt_base (and + * @map->phys_base). + * + * Returns 0 on success and a negative error code in case of error. + */ +int pci_epc_mem_map(struct pci_epc *epc, u8 func_no, u8 vfunc_no, + u64 pci_addr, size_t pci_size, struct pci_epc_map *map) +{ + int ret; + + ret = pci_epc_map_align(epc, func_no, vfunc_no, pci_addr, pci_size, map); + if (ret) + return ret; + + map->virt_base = pci_epc_mem_alloc_addr(epc, &map->phys_base, + map->map_size); + if (!map->virt_base) + return -ENOMEM; + + map->phys_addr = map->phys_base + map->map_ofst; + map->virt_addr = map->virt_base + map->map_ofst; + + ret = pci_epc_map_addr(epc, func_no, vfunc_no, map->phys_base, + map->map_pci_addr, map->map_size); + if (ret) { + pci_epc_mem_free_addr(epc, map->phys_base, map->virt_base, + map->map_size); + map->virt_base = 0; + return ret; + } + + return 0; +} +EXPORT_SYMBOL_GPL(pci_epc_mem_map); + +/** + * pci_epc_mem_unmap() - unmap and free a CPU address region + * @epc: the EPC device on which the CPU address is allocated and mapped + * @func_no: the physical endpoint function number in the EPC device + * @vfunc_no: the virtual endpoint function number in the physical function + * @map: the mapping information + * + * Unmap and free a CPU address region that was allocated and mapped with + * pci_epc_mem_map(). + */ +void pci_epc_mem_unmap(struct pci_epc *epc, u8 func_no, u8 vfunc_no, + struct pci_epc_map *map) +{ + if (!pci_epc_function_is_valid(epc, func_no, vfunc_no)) + return; + + if (!map || !map->virt_base) + return; + + pci_epc_unmap_addr(epc, func_no, vfunc_no, map->phys_base); + pci_epc_mem_free_addr(epc, map->phys_base, map->virt_base, + map->map_size); + map->map_size = 0; +} +EXPORT_SYMBOL_GPL(pci_epc_mem_unmap); + /** * pci_epc_clear_bar() - reset the BAR * @epc: the EPC device for which the BAR has to be cleared diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h index 9df8a83e8d10..97d2fbb740fd 100644 --- a/include/linux/pci-epc.h +++ b/include/linux/pci-epc.h @@ -315,6 +315,10 @@ void __iomem *pci_epc_mem_alloc_addr(struct pci_epc *epc, phys_addr_t *phys_addr, size_t size); void pci_epc_mem_free_addr(struct pci_epc *epc, phys_addr_t phys_addr, void __iomem *virt_addr, size_t size); +int pci_epc_mem_map(struct pci_epc *epc, u8 func_no, u8 vfunc_no, + u64 pci_addr, size_t pci_size, struct pci_epc_map *map); +void pci_epc_mem_unmap(struct pci_epc *epc, u8 func_no, u8 vfunc_no, + struct pci_epc_map *map); #else static inline void pci_epc_init_notify(struct pci_epc *epc)