From nobody Mon Feb 9 15:08:32 2026 Received: from mx0a-00082601.pphosted.com (mx0a-00082601.pphosted.com [67.231.145.42]) (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 CFF6728D829; Tue, 11 Nov 2025 14:52:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=67.231.145.42 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762872758; cv=none; b=iaxGpY0bgccrz3nIOAz8CdX9/EcX3Dtq90TcObSxOpV/9Phwbmj5BdpMUNiOgygm4kqZvqfuTgk+oLgefKfEkkPcbYn3DYo7HBpGakSeV3sDUUbbvu6ZcxUBVZNtSI0WJHgz7+/Vbma1VgsknfgfDTKlsyYH/lmo90nYYUCnaeI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762872758; c=relaxed/simple; bh=VhDxEgPasP8lYcHW4kqVTS8L3eb6Y4YGcg+MMM89DkM=; h=From:Date:Subject:MIME-Version:Content-Type:Message-ID:References: In-Reply-To:To:CC; b=aqdzpqV749Q3cw+O72km+xqUFqSISie7kqQN0T0Q3REEmI2LfeHnk7bsKKnJ+TORA8lyFg9okPx/85AKsf+wxdiTcS6fo0E30r4w4IxLMPIf4sE80Xd4wHTmC52F6WY/1MnsnGswQRqG2f0f/xXyEO7T1FysHUZzN7SzqbhFdRk= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=fb.com; spf=pass smtp.mailfrom=meta.com; dkim=pass (2048-bit key) header.d=fb.com header.i=@fb.com header.b=3Z2hhjTl; arc=none smtp.client-ip=67.231.145.42 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=fb.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=meta.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=fb.com header.i=@fb.com header.b="3Z2hhjTl" Received: from pps.filterd (m0148461.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.18.1.11/8.18.1.11) with ESMTP id 5AB7SXNJ1282474; Tue, 11 Nov 2025 06:52:31 -0800 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=cc :content-transfer-encoding:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to; s=s2048-2025-q2; bh=4ZaUVck6S6J48bKwbMsq4gVF+BpB0wOt3hBiWKgOrPw=; b=3Z2hhjTl4oIW 46KZEOTc7kT9U/ZKxSRsFFqAWcauL2nq+ARfDhwq6birPXMz5rEStPfA0hqptcWQ Xqezqg16hhvlJ+B2irkRyRbgox0zpq9DxYpl9TDk8HrwfJgY0oM02ptWiED8BLNP FGq4/aoetdKgCotuxS2gqAP6mmy2mFRdl1kVsCTO3wUKUHO00H4HypHV4hohIQcx UtoQCGThPGmpG6yPorCFxHkp5pylLKGYBPk0RnhpPL+tJXiOkh2EEWwe+3+GtDYM tGyeeY70PAwMGX1zM7Mge4HD9zEZLyvl8jmYssC9dfip04iQtvuqf7AXnXaiWIQ5 UPNrIr87/w== Received: from mail.thefacebook.com ([163.114.134.16]) by mx0a-00082601.pphosted.com (PPS) with ESMTPS id 4ac0shadt9-4 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT); Tue, 11 Nov 2025 06:52:30 -0800 (PST) Received: from devgpu015.cco6.facebook.com (2620:10d:c085:108::150d) by mail.thefacebook.com (2620:10d:c08b:78::2ac9) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.2.2562.20; Tue, 11 Nov 2025 14:52:29 +0000 From: Alex Mastro Date: Tue, 11 Nov 2025 06:52:04 -0800 Subject: [PATCH v2 3/4] vfio: selftests: add iova allocator Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-ID: <20251111-iova-ranges-v2-3-0fa267ff9b78@fb.com> References: <20251111-iova-ranges-v2-0-0fa267ff9b78@fb.com> In-Reply-To: <20251111-iova-ranges-v2-0-0fa267ff9b78@fb.com> To: Alex Williamson , David Matlack , Shuah Khan , Jason Gunthorpe CC: , , , Alex Mastro X-Mailer: b4 0.13.0 X-Authority-Analysis: v=2.4 cv=Pf/yRyhd c=1 sm=1 tr=0 ts=69134dae cx=c_pps a=CB4LiSf2rd0gKozIdrpkBw==:117 a=CB4LiSf2rd0gKozIdrpkBw==:17 a=IkcTkHD0fZMA:10 a=6UeiqGixMTsA:10 a=VkNPw1HP01LnGYTKEx00:22 a=VwQbUJbxAAAA:8 a=r1p2_3pzAAAA:8 a=FOH2dFAWAAAA:8 a=jdgmLsG8W1E4BNsLh0EA:9 a=QEXdDO2ut3YA:10 a=r_pkcD-q9-ctt7trBg_g:22 a=cPQSjfK2_nFv0Q5t_7PE:22 X-Proofpoint-GUID: YEFXIK-Mia_QKM5caj7scJhaAcB7zsiE X-Proofpoint-Spam-Details-Enc: AW1haW4tMjUxMTExMDExOSBTYWx0ZWRfX5qdHqNwDnwzu n6prwavDGeRM0Hvx2U9d1uqmUudd6ykFlI3UUZzMJ/Pu8pImNKctfL4oFBjQUzmeZaQYzUFvGqE wHZBJivHJc2M14J6MRuCrBI0BLNAOJL0p/UUX7PzlWlaHlu7l6VLwJ1/L3zsgqfcoQ9CHRpX95O PxA9DUB265VbbcPihLEAznX3N4x0e70rAN91o5t1T2GYKj8yep3np1Kh2Q0aeszcEMqC6Lbs6f1 tk4Jg9ezrYoyXMoI0kay5Ffi6oPmGVH0X32DzY9DDIcLFNrGiwrxj6aIboc3swB0UdJKEuGj/Hm k5xdt8c1OqtXwZ0O5xT3tMlUr0opBJbWiUaRsuGZzPXbQH5SuJ4W+H0NYxmvWDth9Qv/XClkg7h cldegDLMQBl9T/7g3LGvULmYl4A8og== X-Proofpoint-ORIG-GUID: YEFXIK-Mia_QKM5caj7scJhaAcB7zsiE X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1121,Hydra:6.1.9,FMLib:17.12.100.49 definitions=2025-11-11_02,2025-11-11_02,2025-10-01_01 Add struct iova_allocator, which gives tests a convenient way to generate legally-accessible IOVAs to map. This allocator traverses the sorted available IOVA ranges linearly, requires power-of-two size allocations, and does not support freeing iova allocations. The assumption is that tests are not IOVA space-bounded, and will not need to recycle IOVAs. This is based on Alex Williamson's patch series for adding an IOVA allocator [1]. [1] https://lore.kernel.org/all/20251108212954.26477-1-alex@shazbot.org/ Signed-off-by: Alex Mastro --- The unfolded code uses David's range_offset suggestion because it makes assignment of the updated state simpler when crossing a range boundary. No more ALIGN(). The insight is that the initial check for sufficient space (pre-alignment) requires computing last =3D iova + size - 1 which is already half of what ALIGN() does. Just masking is left. --- --- .../testing/selftests/vfio/lib/include/vfio_util.h | 11 ++++ tools/testing/selftests/vfio/lib/vfio_pci_device.c | 74 ++++++++++++++++++= +++- 2 files changed, 84 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/vfio/lib/include/vfio_util.h b/tools/t= esting/selftests/vfio/lib/include/vfio_util.h index ef8f06ef0c13..69ec0c856481 100644 --- a/tools/testing/selftests/vfio/lib/include/vfio_util.h +++ b/tools/testing/selftests/vfio/lib/include/vfio_util.h @@ -188,6 +188,13 @@ struct vfio_pci_device { struct vfio_pci_driver driver; }; =20 +struct iova_allocator { + struct iommu_iova_range *ranges; + u32 nranges; + u32 range_idx; + u64 range_offset; +}; + /* * Return the BDF string of the device that the test should use. * @@ -212,6 +219,10 @@ void vfio_pci_device_reset(struct vfio_pci_device *dev= ice); struct iommu_iova_range *vfio_pci_iova_ranges(struct vfio_pci_device *devi= ce, u32 *nranges); =20 +struct iova_allocator *iova_allocator_init(struct vfio_pci_device *device); +void iova_allocator_cleanup(struct iova_allocator *allocator); +iova_t iova_allocator_alloc(struct iova_allocator *allocator, size_t size); + int __vfio_pci_dma_map(struct vfio_pci_device *device, struct vfio_dma_region *region); int __vfio_pci_dma_unmap(struct vfio_pci_device *device, diff --git a/tools/testing/selftests/vfio/lib/vfio_pci_device.c b/tools/tes= ting/selftests/vfio/lib/vfio_pci_device.c index 7a523e3f2dce..ff1edb11747a 100644 --- a/tools/testing/selftests/vfio/lib/vfio_pci_device.c +++ b/tools/testing/selftests/vfio/lib/vfio_pci_device.c @@ -12,11 +12,12 @@ #include =20 #include +#include #include #include +#include #include #include -#include =20 #include "../../../kselftest.h" #include @@ -196,6 +197,77 @@ struct iommu_iova_range *vfio_pci_iova_ranges(struct v= fio_pci_device *device, return ranges; } =20 +struct iova_allocator *iova_allocator_init(struct vfio_pci_device *device) +{ + struct iova_allocator *allocator; + struct iommu_iova_range *ranges; + u32 nranges; + + ranges =3D vfio_pci_iova_ranges(device, &nranges); + VFIO_ASSERT_NOT_NULL(ranges); + + allocator =3D malloc(sizeof(*allocator)); + VFIO_ASSERT_NOT_NULL(allocator); + + *allocator =3D (struct iova_allocator){ + .ranges =3D ranges, + .nranges =3D nranges, + .range_idx =3D 0, + .range_offset =3D 0, + }; + + return allocator; +} + +void iova_allocator_cleanup(struct iova_allocator *allocator) +{ + free(allocator->ranges); + free(allocator); +} + +iova_t iova_allocator_alloc(struct iova_allocator *allocator, size_t size) +{ + VFIO_ASSERT_GT(size, 0, "Invalid size arg, zero\n"); + VFIO_ASSERT_EQ(size & (size - 1), 0, "Invalid size arg, non-power-of-2\n"= ); + + for (;;) { + struct iommu_iova_range *range; + iova_t iova, last; + + VFIO_ASSERT_LT(allocator->range_idx, allocator->nranges, + "IOVA allocator out of space\n"); + + range =3D &allocator->ranges[allocator->range_idx]; + iova =3D range->start + allocator->range_offset; + + /* Check for sufficient space at the current offset */ + if (check_add_overflow(iova, size - 1, &last) || + last > range->last) + goto next_range; + + /* Align iova to size */ + iova =3D last & ~(size - 1); + + /* Check for sufficient space at the aligned iova */ + if (check_add_overflow(iova, size - 1, &last) || + last > range->last) + goto next_range; + + if (last =3D=3D range->last) { + allocator->range_idx++; + allocator->range_offset =3D 0; + } else { + allocator->range_offset =3D last - range->start + 1; + } + + return iova; + +next_range: + allocator->range_idx++; + allocator->range_offset =3D 0; + } +} + iova_t __to_iova(struct vfio_pci_device *device, void *vaddr) { struct vfio_dma_region *region; --=20 2.47.3