From patchwork Thu Feb 20 22:40:30 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sergio Lopez X-Patchwork-Id: 13984565 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 9F93CC021B2 for ; Thu, 20 Feb 2025 22:41:10 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 1DB0F10E9EB; Thu, 20 Feb 2025 22:41:10 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.b="CJjDq89J"; dkim-atps=neutral Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by gabe.freedesktop.org (Postfix) with ESMTPS id E585110E9EB for ; Thu, 20 Feb 2025 22:41:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1740091268; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=1KVhFVLcrq0MwE18FSmJzB1oSZy7QOKz+o8BK19VMfs=; b=CJjDq89JuLuL06EJoF5TQ1ZMgKXm8u1jovI5w7gIzFCj9tkKmYHK696DgJVG2Rkrv4x3b8 exlOLh2TCA+XSajGHvyyTXKPr6PHPwWJ0zBqiNnz7duKca1Qcx3MmhyRh/YKww4rYTVhge p1jVtIc/ip0A+QTkOE9Xa0iXx2VCBjc= Received: from mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-251-NQYkDMMMMc6lP83Dh1jTYA-1; Thu, 20 Feb 2025 17:41:04 -0500 X-MC-Unique: NQYkDMMMMc6lP83Dh1jTYA-1 X-Mimecast-MFC-AGG-ID: NQYkDMMMMc6lP83Dh1jTYA_1740091263 Received: from mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.93]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id B520819373DC; Thu, 20 Feb 2025 22:41:02 +0000 (UTC) Received: from [127.0.1.1] (unknown [10.44.32.26]) by mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 6E96B1800D96; Thu, 20 Feb 2025 22:40:56 +0000 (UTC) From: Sergio Lopez Date: Thu, 20 Feb 2025 23:40:30 +0100 Subject: [PATCH RFC v4 1/4] virtio: introduce VIRTIO_F_SHM_PAGE_SIZE MIME-Version: 1.0 Message-Id: <20250220-virtio-shm-page-size-v4-1-ddaed7b6f734@redhat.com> References: <20250220-virtio-shm-page-size-v4-0-ddaed7b6f734@redhat.com> In-Reply-To: <20250220-virtio-shm-page-size-v4-0-ddaed7b6f734@redhat.com> To: "Michael S. Tsirkin" , Daniel Verkamp , Jason Wang , Xuan Zhuo , =?utf-8?q?Eugenio_P=C3=A9rez?= , David Airlie , Gerd Hoffmann , Gurchetan Singh , Chia-I Wu , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , Simona Vetter , Rob Clark , Dmitry Osipenko , fnkl.kernel@gmail.com Cc: virtualization@lists.linux.dev, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, Sergio Lopez X-Developer-Signature: v=1; a=openpgp-sha256; l=2407; i=slp@redhat.com; h=from:subject:message-id; bh=mRGswsKourNVCaSODc/n1NTXWr1ln5mIzOK1iDX0YHA=; b=owEBbQKS/ZANAwAIAfRpJ40vDAI1AcsmYgBnt69rNaApFMtsFfuvcVdoXvsq5VoZddtLVwtzB iLIBEoYegWJAjMEAAEIAB0WIQS+1fz3US2GgJFC6KL0aSeNLwwCNQUCZ7evawAKCRD0aSeNLwwC NSU3D/0epEm/Iz+J0xyvWT0cojPJldJU0xWq/zjXQ0FXd01iypGAieK+heQnMejXs0hA3bpDWdt /F0MEpKeNBEi8DCwWRgSn9Hu/2iQZ/WvXIwpYUAs+6xN9kfb8HlY6FeZLK8JIarb+PrTCWXodLK cXIA7tZSgPtou56F+sj6yMkBNdhsh8JIur8cwjYYkDxaG4jliDcFfsXDbyWi9ml70pPbUuiRIrC Bc7CVWJqOhy0ZL6yZ+Hk/Pi2zaD/bfHFoMTwt/HmAMDbYx7bILy698QWk9QLjEr//YbGHssJbEe bYTVg8czPAGjFO/FlAJ0ca8fz6t7b8do61XFD005nkHa3WC68yfTQ2Y6wQuGFWe35fuf1YG4chx mm4TehBJVbL1IICa0kEuqnxgDaGRP2elT8gUNuO8lZhVifluXLxBG1GtrlNgHECjyrjXniUAk7V JHfcTqQq7hjWXHLKZPqqsLKW64weEBuU0KQmayMTvr+r4UqrN84cjarVfKD8THuEnNEDX1vBfA4 m3zxBExmBt+LedcPbdlAt3gJ4srNC1qUVwBfpaJ88EvIKcUt13Go2zcJPZG1fA79sM/O12SZv1m 54X+SoIRwcM91Jgl2szarSI3XoYRrgsTtGg+rGmm8UpGchMbZn7GiGrE5Bc2SRffJ4ZYXPF8gZI /EZWitdXX7+b3Pg== X-Developer-Key: i=slp@redhat.com; a=openpgp; fpr=BED5FCF7512D86809142E8A2F469278D2F0C0235 X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Introduce VIRTIO_F_SHM_PAGE_SIZE, a feature bit which indicates that the transport provides the page size for SHM regions. Reviewed-by: Dmitry Osipenko Signed-off-by: Sergio Lopez --- drivers/virtio/virtio_pci_modern.c | 3 +++ drivers/virtio/virtio_ring.c | 2 ++ include/uapi/linux/virtio_config.h | 7 ++++++- 3 files changed, 11 insertions(+), 1 deletion(-) diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c index 5eaade7578606e4b02af0d66447417ad6aa11064..104ba08f82d4a6268240bbad15385dd44b3a71d6 100644 --- a/drivers/virtio/virtio_pci_modern.c +++ b/drivers/virtio/virtio_pci_modern.c @@ -367,6 +367,9 @@ static void vp_transport_features(struct virtio_device *vdev, u64 features) if (features & BIT_ULL(VIRTIO_F_ADMIN_VQ)) __virtio_set_bit(vdev, VIRTIO_F_ADMIN_VQ); + + if (features & BIT_ULL(VIRTIO_F_SHM_PAGE_SIZE)) + __virtio_set_bit(vdev, VIRTIO_F_SHM_PAGE_SIZE); } static int __vp_check_common_size_one_feature(struct virtio_device *vdev, u32 fbit, diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index fdd2d2b07b5a2aca864bc917306536685afb66a6..d853d5cf7e553be8bbe0ff461dc7312b258c6e58 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -2983,6 +2983,8 @@ void vring_transport_features(struct virtio_device *vdev) break; case VIRTIO_F_NOTIFICATION_DATA: break; + case VIRTIO_F_SHM_PAGE_SIZE: + break; default: /* We don't understand this bit. */ __virtio_clear_bit(vdev, i); diff --git a/include/uapi/linux/virtio_config.h b/include/uapi/linux/virtio_config.h index 2445f365bce74b4e926c6929322b269252ab6830..3171e3792263c2cd472ac09da18e593ab400751d 100644 --- a/include/uapi/linux/virtio_config.h +++ b/include/uapi/linux/virtio_config.h @@ -52,7 +52,7 @@ * rest are per-device feature bits. */ #define VIRTIO_TRANSPORT_F_START 28 -#define VIRTIO_TRANSPORT_F_END 42 +#define VIRTIO_TRANSPORT_F_END 43 #ifndef VIRTIO_CONFIG_NO_LEGACY /* Do we get callbacks when the ring is completely used, even if we've @@ -120,4 +120,9 @@ */ #define VIRTIO_F_ADMIN_VQ 41 +/* + * This feature indicates that the transport provides the SHM page size. + */ +#define VIRTIO_F_SHM_PAGE_SIZE 42 + #endif /* _UAPI_LINUX_VIRTIO_CONFIG_H */ From patchwork Thu Feb 20 22:40:31 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sergio Lopez X-Patchwork-Id: 13984566 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A5A90C021B3 for ; 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Thu, 20 Feb 2025 17:41:11 -0500 X-MC-Unique: -ymU3MD2M2-xoYuMkle9wg-1 X-Mimecast-MFC-AGG-ID: -ymU3MD2M2-xoYuMkle9wg_1740091270 Received: from mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.93]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 8A20F1800982; Thu, 20 Feb 2025 22:41:09 +0000 (UTC) Received: from [127.0.1.1] (unknown [10.44.32.26]) by mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 4C9071800D96; Thu, 20 Feb 2025 22:41:03 +0000 (UTC) From: Sergio Lopez Date: Thu, 20 Feb 2025 23:40:31 +0100 Subject: [PATCH RFC v4 2/4] virtio-pci: extend virtio_pci_cap with page_shift MIME-Version: 1.0 Message-Id: <20250220-virtio-shm-page-size-v4-2-ddaed7b6f734@redhat.com> References: <20250220-virtio-shm-page-size-v4-0-ddaed7b6f734@redhat.com> In-Reply-To: <20250220-virtio-shm-page-size-v4-0-ddaed7b6f734@redhat.com> To: "Michael S. Tsirkin" , Daniel Verkamp , Jason Wang , Xuan Zhuo , =?utf-8?q?Eugenio_P=C3=A9rez?= , David Airlie , Gerd Hoffmann , Gurchetan Singh , Chia-I Wu , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , Simona Vetter , Rob Clark , Dmitry Osipenko , fnkl.kernel@gmail.com Cc: virtualization@lists.linux.dev, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, Sergio Lopez X-Developer-Signature: v=1; a=openpgp-sha256; l=5186; i=slp@redhat.com; h=from:subject:message-id; bh=fZBejds3HxqJhAuzRZLMFlVcJOBja/rtJP0lwiQ8O5E=; b=owEBbQKS/ZANAwAIAfRpJ40vDAI1AcsmYgBnt69s4aAv98lez51Dix//1YmMYHMENrdboZrQB 9DYOfByMhqJAjMEAAEIAB0WIQS+1fz3US2GgJFC6KL0aSeNLwwCNQUCZ7evbAAKCRD0aSeNLwwC NXcvEACp7nTShPCmE5cAB83dIYQqfN2w0uMbywW1NZ3RIJm9opp7FPpykU/R/YI4hr8AOLv91yK GnAx9DCuCH96cNO6hO6saxk67d+0Ofz14BDkoIn+/hjZDbq02GdU8YOcrpLSRMyJh7/n202TFgP VNErQ9NjEjfzNUbntqdSQDTiWy8oyCMu3Z+xTX2b6xB2PA70my3/q0Mi2wv8Eqqs/0+q7ZQXxwf JCqJUpcgsKgjlihy+mrNfZ6ZV9AiwBjfzbqx+zIVUimqHODas3Yz39hL6R1ZjaQ+7hpvUl9RtGi n/jz6qFtTYlgr6bjG2eGmkakvm6VuEWKKPwewRGCa+oM0q9B+Un5NBRDZHUpmZRzvDVFDkMP9fX Bi0Zw2DZTsYyvRSPcYFZv8qVJX9kfqb7tI2k9HD3K6Io4P31yN6Kj8h3/hs3IbGzfVRBwJoqDXf zHuFdjhFy9xLkK9pRgHT8pkjQThbwwb+AbGN55AnK/0ExEue1c3cKsP5jkpABRfrK4D0on/Hee8 1Rr8PcxPkLgXHqQb+4liOSbaesPQQr6oJDivBnazD8ne/XpgohIyw9ZaUMvFVIrPfRcZZnQZl5c nJQa3RzwbV9o2Kww+zlcwsKITJs42rRuyw/naqAgAC4DKIr+fqDxG4ehalnzbK4rR3tb2bxrZOw PXv16eyPKD2vWvw== X-Developer-Key: i=slp@redhat.com; a=openpgp; fpr=BED5FCF7512D86809142E8A2F469278D2F0C0235 X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" If VIRTIO_F_SHM_PAGE_SIZE has been negotiated and cfg_type is VIRTIO_PCI_CAP_SHARED_MEMORY_CFG, the driver must read the page_shift field, derive the supported page size from it, and honor it when requesting the map of memory into the shared memory region to the device. Extend virtio_pci_cap to hold that field, and use it to feed virtio_shm_region with the corresponding page size. Reviewed-by: Dmitry Osipenko Reviewed-by: Daniel Verkamp Signed-off-by: Sergio Lopez --- drivers/virtio/virtio_mmio.c | 2 ++ drivers/virtio/virtio_pci_modern.c | 29 +++++++++++++++++++++++++---- include/linux/virtio_config.h | 1 + include/uapi/linux/virtio_pci.h | 3 ++- 4 files changed, 30 insertions(+), 5 deletions(-) diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c index 5d78c2d572abfcfe2b84cdd82df622320fe97d5d..1f594b626d7a7734e8ec58766737a118c26bad94 100644 --- a/drivers/virtio/virtio_mmio.c +++ b/drivers/virtio/virtio_mmio.c @@ -560,6 +560,8 @@ static bool vm_get_shm_region(struct virtio_device *vdev, region->addr = addr; + region->page_size = 4096; + return true; } diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c index 104ba08f82d4a6268240bbad15385dd44b3a71d6..2c83b4a261e62614a6526ea13e41f2a05af34cad 100644 --- a/drivers/virtio/virtio_pci_modern.c +++ b/drivers/virtio/virtio_pci_modern.c @@ -770,14 +770,15 @@ static void del_vq(struct virtio_pci_vq_info *info) vring_del_virtqueue(vq); } -static int virtio_pci_find_shm_cap(struct pci_dev *dev, u8 required_id, - u8 *bar, u64 *offset, u64 *len) +static int virtio_pci_find_shm_cap(struct virtio_device *vdev, struct pci_dev *dev, + u8 required_id, u8 *bar, u64 *offset, u64 *len, + u32 *page_size) { int pos; for (pos = pci_find_capability(dev, PCI_CAP_ID_VNDR); pos > 0; pos = pci_find_next_capability(dev, pos, PCI_CAP_ID_VNDR)) { - u8 type, cap_len, id, res_bar; + u8 type, cap_len, id, res_bar, page_shift = 0; u32 tmp32; u64 res_offset, res_length; @@ -808,6 +809,23 @@ static int virtio_pci_find_shm_cap(struct pci_dev *dev, u8 required_id, * Looks good. */ + /* Read the page shift if supported. The page_shift variable is + * initialized to zero above, so if this feature isn't supported it + * will result in a page_size of 4096, a default safe value. + */ + if (__virtio_test_bit(vdev, VIRTIO_F_SHM_PAGE_SIZE)) { + pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap, + page_shift), &page_shift); + /* The value derived from page_shift must fit into a 32-bit + * unsigned integer. + */ + if ((page_shift + 12) >= 32) { + dev_err(&dev->dev, "%s: shm cap with bad page shift: %d\n", + __func__, page_shift); + continue; + } + } + /* Read the lower 32bit of length and offset */ pci_read_config_dword(dev, pos + offsetof(struct virtio_pci_cap, offset), &tmp32); @@ -829,6 +847,7 @@ static int virtio_pci_find_shm_cap(struct pci_dev *dev, u8 required_id, *bar = res_bar; *offset = res_offset; *len = res_length; + *page_size = 1U << (page_shift + 12); return pos; } @@ -841,11 +860,12 @@ static bool vp_get_shm_region(struct virtio_device *vdev, struct virtio_pci_device *vp_dev = to_vp_device(vdev); struct pci_dev *pci_dev = vp_dev->pci_dev; u8 bar; + u32 page_size; u64 offset, len; phys_addr_t phys_addr; size_t bar_len; - if (!virtio_pci_find_shm_cap(pci_dev, id, &bar, &offset, &len)) + if (!virtio_pci_find_shm_cap(vdev, pci_dev, id, &bar, &offset, &len, &page_size)) return false; phys_addr = pci_resource_start(pci_dev, bar); @@ -865,6 +885,7 @@ static bool vp_get_shm_region(struct virtio_device *vdev, region->len = len; region->addr = (u64) phys_addr + offset; + region->page_size = page_size; return true; } diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h index 169c7d367facb36dcabf9596068580ea8b8516c7..c1b2ce71ea55e81978e18db05494deab193fa4fb 100644 --- a/include/linux/virtio_config.h +++ b/include/linux/virtio_config.h @@ -14,6 +14,7 @@ struct irq_affinity; struct virtio_shm_region { u64 addr; u64 len; + u32 page_size; }; typedef void vq_callback_t(struct virtqueue *); diff --git a/include/uapi/linux/virtio_pci.h b/include/uapi/linux/virtio_pci.h index 8549d4571257142ac6c9dad5c01369923791a85a..1a76df52b4eccf548df78a8ee7d3a04591f55522 100644 --- a/include/uapi/linux/virtio_pci.h +++ b/include/uapi/linux/virtio_pci.h @@ -127,7 +127,8 @@ struct virtio_pci_cap { __u8 cfg_type; /* Identifies the structure. */ __u8 bar; /* Where to find it. */ __u8 id; /* Multiple capabilities of the same type */ - __u8 padding[2]; /* Pad to full dword. */ + __u8 page_shift; /* Page shift for VIRTIO_PCI_CAP_SHARED_MEMORY_CFG. */ + __u8 padding[1]; /* Pad to full dword. */ __le32 offset; /* Offset within bar. */ __le32 length; /* Length of the structure, in bytes. */ }; From patchwork Thu Feb 20 22:40:32 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sergio Lopez X-Patchwork-Id: 13984567 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 2E6E3C021B3 for ; Thu, 20 Feb 2025 22:41:27 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 7770210E9ED; 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Thu, 20 Feb 2025 17:41:20 -0500 X-MC-Unique: XiyJNyuFOnuNGvTbdyAzBg-1 X-Mimecast-MFC-AGG-ID: XiyJNyuFOnuNGvTbdyAzBg_1740091278 Received: from mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.93]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 9F7F21979057; Thu, 20 Feb 2025 22:41:17 +0000 (UTC) Received: from [127.0.1.1] (unknown [10.44.32.26]) by mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 1CA6F1800359; Thu, 20 Feb 2025 22:41:09 +0000 (UTC) From: Sergio Lopez Date: Thu, 20 Feb 2025 23:40:32 +0100 Subject: [PATCH RFC v4 3/4] virtio-mmio: read shm region page size MIME-Version: 1.0 Message-Id: <20250220-virtio-shm-page-size-v4-3-ddaed7b6f734@redhat.com> References: <20250220-virtio-shm-page-size-v4-0-ddaed7b6f734@redhat.com> In-Reply-To: <20250220-virtio-shm-page-size-v4-0-ddaed7b6f734@redhat.com> To: "Michael S. Tsirkin" , Daniel Verkamp , Jason Wang , Xuan Zhuo , =?utf-8?q?Eugenio_P=C3=A9rez?= , David Airlie , Gerd Hoffmann , Gurchetan Singh , Chia-I Wu , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , Simona Vetter , Rob Clark , Dmitry Osipenko , fnkl.kernel@gmail.com Cc: virtualization@lists.linux.dev, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, Sergio Lopez X-Developer-Signature: v=1; a=openpgp-sha256; l=2425; i=slp@redhat.com; h=from:subject:message-id; bh=Ehj8/j16O8eT/oyoXvssheCZbXxBfefe7YN3dkYS8pA=; b=owEBbQKS/ZANAwAIAfRpJ40vDAI1AcsmYgBnt69txYXyawKpopF3mRu4vuKWWmiWXOzHXeg8b dlMQo7n/g6JAjMEAAEIAB0WIQS+1fz3US2GgJFC6KL0aSeNLwwCNQUCZ7evbQAKCRD0aSeNLwwC Ne4cD/9Y14GppRUWfTPTUgZUvWhFCX3/t575waWpyGh3UONuPgsMzIRajm0Lrse4JWGg/SefzA3 2DC8qKFJJIx3HS8iaROUiGHLsSyiTe6n9bj5Me8dlK583tSJZ8KVpyUijwZXhRhQCvQX+EWSjjj 5dhsLhFW9x2rTlyO4MvB5iOg+Z5MUezx2ocpqZ90/9LCXD/w6hX75sOkbI3bOQVD4O6FUYRal6+ M1xDA0afOROOn3pCApNHw3ZWVkpNkllX0CxvpwpKChdnB33Uj/ZAkHwMnLHONrGMS800kokTS+O wOWf2vXGHOz2akaIEhqbSH3dh47Xer2qQWMyBWM35cksHqzCJgKA1AkcZSHX0h0aedPYg3ZGq9y 5Pj3crXk10uivWk8hudxf13Kaf1YAKoSEOOowTWz9A790vmjG4HlOpJpdRHkXC3SByLB+lyPWv9 mX95mD4vb8g6w+oNOJros1NmnId8NMwl01LVJ/gHHBmQCTWoTQXoFJgOGZONrsag1U6GCaqWhrr 9/2T26PdzOrwjwI3kMwj13yhe7neaNvgYwOuX8RtPFc7MqeNWwl6axXMVCsPmMMcC/c+aPeuL0D w4Ryz81KwoxNtQ0gJmsJ45HcQ3dPCvJ14Lu5HmAQvTeP+FqGqJMcmZ6rwpZ+L597nrRm3Nr6XWn PVlKyHMJVE/d0lA== X-Developer-Key: i=slp@redhat.com; a=openpgp; fpr=BED5FCF7512D86809142E8A2F469278D2F0C0235 X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Use the newly introduced SHM_PAGE_SHIFT register to read the page shift for the shared memory region, derive the page size from it and store the resulting value into virtio_shm_region. Reviewed-by: Dmitry Osipenko Signed-off-by: Sergio Lopez --- drivers/virtio/virtio_mmio.c | 20 +++++++++++++++++++- include/uapi/linux/virtio_mmio.h | 3 +++ 2 files changed, 22 insertions(+), 1 deletion(-) diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c index 1f594b626d7a7734e8ec58766737a118c26bad94..5532450c9e9935399efbe9c5c6257293b6dcfc9e 100644 --- a/drivers/virtio/virtio_mmio.c +++ b/drivers/virtio/virtio_mmio.c @@ -537,6 +537,7 @@ static bool vm_get_shm_region(struct virtio_device *vdev, struct virtio_shm_region *region, u8 id) { struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev); + u8 page_shift = 0; u64 len, addr; /* Select the region we're interested in */ @@ -560,7 +561,24 @@ static bool vm_get_shm_region(struct virtio_device *vdev, region->addr = addr; - region->page_size = 4096; + /* If supported by the device transport, read the region page size. + * The page_shift variable is initialized to zero above, so if this + * feature isn't supported it will result in a page_size of 4096, a + * default safe value. + */ + if (__virtio_test_bit(vdev, VIRTIO_F_SHM_PAGE_SIZE)) { + page_shift = (u8) readl(vm_dev->base + VIRTIO_MMIO_SHM_PAGE_SHIFT); + /* The value derived from page_shift must fit into a 32-bit + * unsigned integer. + */ + if ((page_shift + 12) >= 32) { + dev_err(&vdev->dev, "%s: device returned an invalid page shift: %d\n", + __func__, page_shift); + return false; + } + } + + region->page_size = 1U << (page_shift + 12); return true; } diff --git a/include/uapi/linux/virtio_mmio.h b/include/uapi/linux/virtio_mmio.h index 0650f91bea6c70f935764070d825d181a2379afb..43348be30eff90ee228b6490b9d3c35ba4c50aa5 100644 --- a/include/uapi/linux/virtio_mmio.h +++ b/include/uapi/linux/virtio_mmio.h @@ -133,6 +133,9 @@ #define VIRTIO_MMIO_SHM_BASE_LOW 0x0b8 #define VIRTIO_MMIO_SHM_BASE_HIGH 0x0bc +/* Shared memory region page shift */ +#define VIRTIO_MMIO_SHM_PAGE_SHIFT 0x0c4 + /* Configuration atomicity value */ #define VIRTIO_MMIO_CONFIG_GENERATION 0x0fc From patchwork Thu Feb 20 22:40:33 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sergio Lopez X-Patchwork-Id: 13984568 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 7840DC021B3 for ; 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Thu, 20 Feb 2025 17:41:26 -0500 X-MC-Unique: 4SwyfRmhO3-NfFiHHVCIgA-1 X-Mimecast-MFC-AGG-ID: 4SwyfRmhO3-NfFiHHVCIgA_1740091284 Received: from mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.93]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 5EB0D18D95E0; Thu, 20 Feb 2025 22:41:24 +0000 (UTC) Received: from [127.0.1.1] (unknown [10.44.32.26]) by mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 34B921800359; Thu, 20 Feb 2025 22:41:17 +0000 (UTC) From: Sergio Lopez Date: Thu, 20 Feb 2025 23:40:33 +0100 Subject: [PATCH RFC v4 4/4] drm/virtio: add VIRTGPU_PARAM_HOST_SHM_PAGE_SIZE to params MIME-Version: 1.0 Message-Id: <20250220-virtio-shm-page-size-v4-4-ddaed7b6f734@redhat.com> References: <20250220-virtio-shm-page-size-v4-0-ddaed7b6f734@redhat.com> In-Reply-To: <20250220-virtio-shm-page-size-v4-0-ddaed7b6f734@redhat.com> To: "Michael S. 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Reviewed-by: Dmitry Osipenko Signed-off-by: Sergio Lopez --- drivers/gpu/drm/virtio/virtgpu_ioctl.c | 5 +++++ include/uapi/drm/virtgpu_drm.h | 1 + 2 files changed, 6 insertions(+) diff --git a/drivers/gpu/drm/virtio/virtgpu_ioctl.c b/drivers/gpu/drm/virtio/virtgpu_ioctl.c index c33c057365f85a2ace536f91655c903036827312..f112b862c2de4d021fb6a54a080f42ad75034227 100644 --- a/drivers/gpu/drm/virtio/virtgpu_ioctl.c +++ b/drivers/gpu/drm/virtio/virtgpu_ioctl.c @@ -117,6 +117,11 @@ static int virtio_gpu_getparam_ioctl(struct drm_device *dev, void *data, case VIRTGPU_PARAM_EXPLICIT_DEBUG_NAME: value = vgdev->has_context_init ? 1 : 0; break; + case VIRTGPU_PARAM_HOST_SHM_PAGE_SIZE: + if (!vgdev->has_host_visible) + return -ENOENT; + value = vgdev->host_visible_region.page_size; + break; default: return -EINVAL; } diff --git a/include/uapi/drm/virtgpu_drm.h b/include/uapi/drm/virtgpu_drm.h index c2ce71987e9bb816d13a300679336cb756f1cbcf..72db6b3339e0dcaf550acbf5ac4381a6e5c2216d 100644 --- a/include/uapi/drm/virtgpu_drm.h +++ b/include/uapi/drm/virtgpu_drm.h @@ -98,6 +98,7 @@ struct drm_virtgpu_execbuffer { #define VIRTGPU_PARAM_CONTEXT_INIT 6 /* DRM_VIRTGPU_CONTEXT_INIT */ #define VIRTGPU_PARAM_SUPPORTED_CAPSET_IDs 7 /* Bitmask of supported capability set ids */ #define VIRTGPU_PARAM_EXPLICIT_DEBUG_NAME 8 /* Ability to set debug name from userspace */ +#define VIRTGPU_PARAM_HOST_SHM_PAGE_SIZE 9 /* Host SHM page size, with format PAGE_SIZE >> 12 */ struct drm_virtgpu_getparam { __u64 param;