From patchwork Fri Nov 16 16:03:06 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hans Verkuil X-Patchwork-Id: 1756141 Return-Path: X-Original-To: patchwork-davinci@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from bear.ext.ti.com (bear.ext.ti.com [192.94.94.41]) by patchwork1.kernel.org (Postfix) with ESMTP id AE5F73FCDE for ; Fri, 16 Nov 2012 16:06:39 +0000 (UTC) Received: from dlelxv30.itg.ti.com ([172.17.2.17]) by bear.ext.ti.com (8.13.7/8.13.7) with ESMTP id qAGG3qUj002897; Fri, 16 Nov 2012 10:03:52 -0600 Received: from DLEE74.ent.ti.com (dlee74.ent.ti.com [157.170.170.8]) by dlelxv30.itg.ti.com (8.13.8/8.13.8) with ESMTP id qAGG3o8Z019926; Fri, 16 Nov 2012 10:03:52 -0600 Received: from dlelxv23.itg.ti.com (172.17.1.198) by DLEE74.ent.ti.com (157.170.170.8) with Microsoft SMTP Server id 14.1.323.3; Fri, 16 Nov 2012 10:03:51 -0600 Received: from linux.omap.com (dlelxs01.itg.ti.com [157.170.227.31]) by dlelxv23.itg.ti.com (8.13.8/8.13.8) with ESMTP id qAGG3pPo020471; Fri, 16 Nov 2012 10:03:51 -0600 Received: from linux.omap.com (localhost [127.0.0.1]) by linux.omap.com (Postfix) with ESMTP id 6381C8062A; Fri, 16 Nov 2012 10:03:51 -0600 (CST) X-Original-To: davinci-linux-open-source@linux.davincidsp.com Delivered-To: davinci-linux-open-source@linux.davincidsp.com Received: from dflp53.itg.ti.com (dflp53.itg.ti.com [128.247.5.6]) by linux.omap.com (Postfix) with ESMTP id 73B2F80627 for ; Fri, 16 Nov 2012 10:03:48 -0600 (CST) Received: from red.ext.ti.com (red.ext.ti.com [192.94.93.37]) by dflp53.itg.ti.com (8.13.8/8.13.8) with ESMTP id qAGG3msd029759 for ; Fri, 16 Nov 2012 10:03:48 -0600 (CST) Received: from psmtp.com (na3sys009amx202.postini.com [74.125.149.42]) by red.ext.ti.com (8.13.7/8.13.7) with SMTP id qAGG3lp8013170 for ; Fri, 16 Nov 2012 10:03:47 -0600 Received: from smtp-vbr19.xs4all.nl ([194.109.24.39]) by na3sys009amx202.postini.com ([74.125.148.10]) with SMTP; Fri, 16 Nov 2012 16:03:47 GMT Received: from alastor.dyndns.org (166.80-203-20.nextgentel.com [80.203.20.166] (may be forged)) (authenticated bits=0) by smtp-vbr19.xs4all.nl (8.13.8/8.13.8) with ESMTP id qAGG3CXZ076468 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=FAIL); Fri, 16 Nov 2012 17:03:12 +0100 (CET) (envelope-from hverkuil@xs4all.nl) Received: from tschai.cisco.com (64-103-25-233.cisco.com [64.103.25.233]) (Authenticated sender: hans) by alastor.dyndns.org (Postfix) with ESMTPSA id DDBA7506007C; Fri, 16 Nov 2012 17:03:10 +0100 (CET) From: Hans Verkuil To: Subject: [RFCv1 PATCH 1/2] vpif_capture: protect dma_queue by a spin_lock. Date: Fri, 16 Nov 2012 17:03:06 +0100 Message-ID: <4d1abc522b7eb1d930105a1f37085324b86ec69c.1353081640.git.hans.verkuil@cisco.com> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1353081787-7010-1-git-send-email-hverkuil@xs4all.nl> References: <1353081787-7010-1-git-send-email-hverkuil@xs4all.nl> X-Virus-Scanned: by XS4ALL Virus Scanner X-pstn-levels: (S:86.54327/99.90000 CV:99.9000 FC:95.5390 LC:95.5390 R:95.9108 P:95.9108 M:97.0282 C:98.6951 ) X-pstn-dkim: 0 skipped:not-enabled X-pstn-settings: 2 (0.5000:0.5000) s cv gt3 gt2 gt1 r p m c X-pstn-addresses: from [82/3] CC: Hans Verkuil , DLOS X-BeenThere: davinci-linux-open-source@linux.davincidsp.com X-Mailman-Version: 2.1.12 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: Errors-To: davinci-linux-open-source-bounces@linux.davincidsp.com From: Hans Verkuil The dma_queue list is accessed by both the interrupt handler and by normal code. It needs to be protected by a lock to prevent possible list corruption. Signed-off-by: Hans Verkuil --- drivers/media/platform/davinci/vpif_capture.c | 26 ++++++++++++++++++++++--- 1 file changed, 23 insertions(+), 3 deletions(-) diff --git a/drivers/media/platform/davinci/vpif_capture.c b/drivers/media/platform/davinci/vpif_capture.c index fcabc02..f4f15f1 100644 --- a/drivers/media/platform/davinci/vpif_capture.c +++ b/drivers/media/platform/davinci/vpif_capture.c @@ -201,13 +201,16 @@ static void vpif_buffer_queue(struct vb2_buffer *vb) struct vpif_cap_buffer *buf = container_of(vb, struct vpif_cap_buffer, vb); struct common_obj *common; + unsigned long flags; common = &ch->common[VPIF_VIDEO_INDEX]; vpif_dbg(2, debug, "vpif_buffer_queue\n"); + spin_lock_irqsave(&common->irqlock, flags); /* add the buffer to the DMA queue */ list_add_tail(&buf->list, &common->dma_queue); + spin_unlock_irqrestore(&common->irqlock, flags); } /** @@ -278,10 +281,13 @@ static int vpif_start_streaming(struct vb2_queue *vq, unsigned int count) struct common_obj *common = &ch->common[VPIF_VIDEO_INDEX]; struct vpif_params *vpif = &ch->vpifparams; unsigned long addr = 0; + unsigned long flags; int ret; - /* If buffer queue is empty, return error */ + /* If buffer queue is empty, return error */ + spin_lock_irqsave(&common->irqlock, flags); if (list_empty(&common->dma_queue)) { + spin_unlock_irqrestore(&common->irqlock, flags); vpif_dbg(1, debug, "buffer queue is empty\n"); return -EIO; } @@ -291,6 +297,7 @@ static int vpif_start_streaming(struct vb2_queue *vq, unsigned int count) struct vpif_cap_buffer, list); /* Remove buffer from the buffer queue */ list_del(&common->cur_frm->list); + spin_unlock_irqrestore(&common->irqlock, flags); /* Mark state of the current frame to active */ common->cur_frm->vb.state = VB2_BUF_STATE_ACTIVE; /* Initialize field_id and started member */ @@ -362,6 +369,7 @@ static int vpif_stop_streaming(struct vb2_queue *vq) struct vpif_fh *fh = vb2_get_drv_priv(vq); struct channel_obj *ch = fh->channel; struct common_obj *common; + unsigned long flags; if (!vb2_is_streaming(vq)) return 0; @@ -369,12 +377,14 @@ static int vpif_stop_streaming(struct vb2_queue *vq) common = &ch->common[VPIF_VIDEO_INDEX]; /* release all active buffers */ + spin_lock_irqsave(&common->irqlock, flags); while (!list_empty(&common->dma_queue)) { common->next_frm = list_entry(common->dma_queue.next, struct vpif_cap_buffer, list); list_del(&common->next_frm->list); vb2_buffer_done(&common->next_frm->vb, VB2_BUF_STATE_ERROR); } + spin_unlock_irqrestore(&common->irqlock, flags); return 0; } @@ -420,10 +430,12 @@ static void vpif_schedule_next_buffer(struct common_obj *common) { unsigned long addr = 0; + spin_lock(&common->irqlock); common->next_frm = list_entry(common->dma_queue.next, struct vpif_cap_buffer, list); /* Remove that buffer from the buffer queue */ list_del(&common->next_frm->list); + spin_unlock(&common->irqlock); common->next_frm->vb.state = VB2_BUF_STATE_ACTIVE; addr = vb2_dma_contig_plane_dma_addr(&common->next_frm->vb, 0); @@ -468,8 +480,12 @@ static irqreturn_t vpif_channel_isr(int irq, void *dev_id) /* Check the field format */ if (1 == ch->vpifparams.std_info.frm_fmt) { /* Progressive mode */ - if (list_empty(&common->dma_queue)) + spin_lock(&common->irqlock); + if (list_empty(&common->dma_queue)) { + spin_unlock(&common->irqlock); continue; + } + spin_unlock(&common->irqlock); if (!channel_first_int[i][channel_id]) vpif_process_buffer_complete(common); @@ -513,9 +529,13 @@ static irqreturn_t vpif_channel_isr(int irq, void *dev_id) vpif_process_buffer_complete(common); } else if (1 == fid) { /* odd field */ + spin_lock(&common->irqlock); if (list_empty(&common->dma_queue) || - (common->cur_frm != common->next_frm)) + (common->cur_frm != common->next_frm)) { + spin_unlock(&common->irqlock); continue; + } + spin_unlock(&common->irqlock); vpif_schedule_next_buffer(common); }