From patchwork Fri May 16 09:21:48 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: wangtao X-Patchwork-Id: 890782 Received: from mta22.hihonor.com (mta22.hihonor.com [81.70.192.198]) (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 5549A222592; Fri, 16 May 2025 09:31:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=81.70.192.198 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747387915; cv=none; b=eC0r/z69sBAtga9UCQsOeR5PznT+grLzgCQ9ORgfH7Ji9dQGKAKw13FlsmZ5GltGLLdDr8fhMtfeue1Sx4HHIgKULXQf21xr9bMUips8PRcRNL/usMNvy1WAgWbPKr68VWLlonX5EXpiOahD15rFZizeh3vysYlPaSDKxi5fiVs= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747387915; c=relaxed/simple; bh=RcNj01AbO/cC3CyRqLPMNfs74/vEnwpl0O3pVr1Qvss=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=UPYHjlsph3+COQGAcQyIMDxhnFEP4ryNEtGm4N9uugaZbNSUaobiOMeQr54DM+z/cJhZgMie5uw6kGLUAydtxQgW0PNMTtunGW8AMa7ly3h7GV3+4W2AQd5q7KdLm8vu9K+FDVgHWsJHIU/1yVShNRcWhEQc7ZmGn9+uD9Yxj30= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=honor.com; spf=pass smtp.mailfrom=honor.com; arc=none smtp.client-ip=81.70.192.198 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=honor.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=honor.com Received: from w001.hihonor.com (unknown [10.68.25.235]) by mta22.hihonor.com (SkyGuard) with ESMTPS id 4ZzMH21lMmzYl1GJ; Fri, 16 May 2025 17:29:34 +0800 (CST) Received: from a010.hihonor.com (10.68.16.52) by w001.hihonor.com (10.68.25.235) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Fri, 16 May 2025 17:31:23 +0800 Received: from localhost.localdomain (10.144.18.117) by a010.hihonor.com (10.68.16.52) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Fri, 16 May 2025 17:31:23 +0800 From: wangtao To: , , , , , CC: , , , , , , , , wangtao Subject: [PATCH v2 2/2] dmabuf/heaps: implement DMA_BUF_IOCTL_RW_FILE for system_heap Date: Fri, 16 May 2025 17:21:48 +0800 Message-ID: <20250516092148.12778-3-tao.wangtao@honor.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20250516092148.12778-1-tao.wangtao@honor.com> References: <20250516092148.12778-1-tao.wangtao@honor.com> Precedence: bulk X-Mailing-List: linux-media@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ClientProxiedBy: w002.hihonor.com (10.68.28.120) To a010.hihonor.com (10.68.16.52) Support direct file I/O operations for system_heap dma-buf objects. Implementation includes: - Check no other drivers use the dmabuf - Construct bio_vec - Set IOCB_DIRECT when O_DIRECT is supported - Invoke vfs_iocb_iter_read()/vfs_iocb_iter_write() for actual I/O Performance metrics (UFS 4.0 device @4GB/s, Arm64 CPU @1GHz): | Metric | 1MB | 8MB | 64MB | 1024MB | 3072MB | |--------------------|--------|--------|---------|----------|----------| | Buffer Read (us) | 1658 | 9028 | 69295 | 1019783 | 2978179 | | Direct Read (us) | 707 | 2647 | 18689 | 299627 | 937758 | | Buffer Rate (MB/s) | 603 | 886 | 924 | 1004 | 1032 | | Direct Rate (MB/s) | 1414 | 3022 | 3425 | 3418 | 3276 | Signed-off-by: wangtao --- drivers/dma-buf/heaps/system_heap.c | 121 ++++++++++++++++++++++++++++ 1 file changed, 121 insertions(+) diff --git a/drivers/dma-buf/heaps/system_heap.c b/drivers/dma-buf/heaps/system_heap.c index 26d5dc89ea16..5ae219ad0d72 100644 --- a/drivers/dma-buf/heaps/system_heap.c +++ b/drivers/dma-buf/heaps/system_heap.c @@ -20,6 +20,8 @@ #include #include #include +#include +#include static struct dma_heap *sys_heap; @@ -281,6 +283,124 @@ static void system_heap_vunmap(struct dma_buf *dmabuf, struct iosys_map *map) iosys_map_clear(map); } +static struct bio_vec *system_heap_init_bvec(struct system_heap_buffer *buffer, + size_t offset, size_t len, int *nr_segs) +{ + struct sg_table *sgt = &buffer->sg_table; + struct scatterlist *sg; + size_t length = 0; + unsigned int i, k = 0; + struct bio_vec *bvec; + size_t sg_left; + size_t sg_offset; + size_t sg_len; + + bvec = kvcalloc(sgt->nents, sizeof(*bvec), GFP_KERNEL); + if (!bvec) + return NULL; + + for_each_sg(sgt->sgl, sg, sgt->nents, i) { + length += sg->length; + if (length <= offset) + continue; + + sg_left = length - offset; + sg_offset = sg->offset + sg->length - sg_left; + sg_len = min(sg_left, len); + + bvec[k].bv_page = sg_page(sg); + bvec[k].bv_len = sg_len; + bvec[k].bv_offset = sg_offset; + k++; + + offset += sg_len; + len -= sg_len; + if (len <= 0) + break; + } + + *nr_segs = k; + return bvec; +} + +static int system_heap_rw_file(struct system_heap_buffer *buffer, bool is_read, + bool direct_io, struct file *filp, loff_t file_offset, + size_t buf_offset, size_t len) +{ + struct bio_vec *bvec; + int nr_segs = 0; + struct iov_iter iter; + struct kiocb kiocb; + ssize_t ret = 0; + + if (!list_empty(&buffer->attachments) || buffer->vmap_cnt) + return -EBUSY; + + if (direct_io) { + if (!(filp->f_mode & FMODE_CAN_ODIRECT)) + return -EINVAL; + } + + bvec = system_heap_init_bvec(buffer, buf_offset, len, &nr_segs); + if (!bvec) + return -ENOMEM; + + iov_iter_bvec(&iter, is_read ? ITER_DEST : ITER_SOURCE, bvec, nr_segs, len); + init_sync_kiocb(&kiocb, filp); + kiocb.ki_pos = file_offset; + if (direct_io) + kiocb.ki_flags |= IOCB_DIRECT; + + while (kiocb.ki_pos < file_offset + len) { + if (is_read) + ret = vfs_iocb_iter_read(filp, &kiocb, &iter); + else + ret = vfs_iocb_iter_write(filp, &kiocb, &iter); + if (ret <= 0) + break; + } + + kvfree(bvec); + return ret < 0 ? ret : 0; +} + +static int system_heap_dma_buf_rw_file(struct dma_buf *dmabuf, + struct dma_buf_rw_file *back) +{ + struct system_heap_buffer *buffer = dmabuf->priv; + int ret = 0; + __u32 op = back->flags & DMA_BUF_RW_FLAGS_OP_MASK; + bool direct_io = back->flags & DMA_BUF_RW_FLAGS_DIRECT; + struct file *filp; + + if (op != DMA_BUF_RW_FLAGS_READ && op != DMA_BUF_RW_FLAGS_WRITE) + return -EINVAL; + if (direct_io) { + if (!PAGE_ALIGNED(back->file_offset) || + !PAGE_ALIGNED(back->buf_offset) || + !PAGE_ALIGNED(back->buf_len)) + return -EINVAL; + } + if (!back->buf_len || back->buf_len > dmabuf->size || + back->buf_offset >= dmabuf->size || + back->buf_offset + back->buf_len > dmabuf->size) + return -EINVAL; + if (back->file_offset + back->buf_len < back->file_offset) + return -EINVAL; + + filp = fget(back->fd); + if (!filp) + return -EBADF; + + mutex_lock(&buffer->lock); + ret = system_heap_rw_file(buffer, op == DMA_BUF_RW_FLAGS_READ, direct_io, + filp, back->file_offset, back->buf_offset, back->buf_len); + mutex_unlock(&buffer->lock); + + fput(filp); + return ret; +} + static void system_heap_dma_buf_release(struct dma_buf *dmabuf) { struct system_heap_buffer *buffer = dmabuf->priv; @@ -308,6 +428,7 @@ static const struct dma_buf_ops system_heap_buf_ops = { .mmap = system_heap_mmap, .vmap = system_heap_vmap, .vunmap = system_heap_vunmap, + .rw_file = system_heap_dma_buf_rw_file, .release = system_heap_dma_buf_release, };