From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Zhang, Jerry (Junwei)" Subject: Re: [PATCH 2/4] dma-buf: lock the reservation object during (un)map_dma_buf v2 Date: Thu, 28 Jun 2018 17:53:59 +0800 Message-ID: <5B34B037.50105@amd.com> References: <20180622141103.1787-1-christian.koenig@amd.com> <20180622141103.1787-3-christian.koenig@amd.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8"; Format="flowed" Content-Transfer-Encoding: base64 Return-path: In-Reply-To: <20180622141103.1787-3-christian.koenig@amd.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" To: =?UTF-8?B?Q2hyaXN0aWFuIEvDtm5pZw==?= , daniel@ffwll.ch, sumit.semwal@linaro.org, dri-devel@lists.freedesktop.org, linux-media@vger.kernel.org, linaro-mm-sig@lists.linaro.org, intel-gfx@lists.freedesktop.org List-Id: dri-devel@lists.freedesktop.org T24gMDYvMjIvMjAxOCAxMDoxMSBQTSwgQ2hyaXN0aWFuIEvDtm5pZyB3cm90ZToKPiBGaXJzdCBz dGVwIHRvd2FyZHMgdW5waW5uZWQgRE1BIGJ1ZiBvcGVyYXRpb24uCj4KPiBJJ3ZlIGNoZWNrZWQg dGhlIERSTSBkcml2ZXJzIHRvIHBvdGVudGlhbCBsb2NraW5nIG9mIHRoZSByZXNlcnZhdGlvbgo+ IG9iamVjdCwgYnV0IGVzc2VudGlhbGx5IHdlIG5lZWQgdG8gYXVkaXQgYWxsIGltcGxlbWVudGF0 aW9ucyBvZiB0aGUKPiBkbWFfYnVmIF9vcHMgZm9yIHRoaXMgdG8gd29yay4KPgo+IHYyOiByZW9y ZGVyZWQKPgo+IFNpZ25lZC1vZmYtYnk6IENocmlzdGlhbiBLw7ZuaWcgPGNocmlzdGlhbi5rb2Vu aWdAYW1kLmNvbT4KCmxvb2tzIGdvb2QgZm9yIG1lLgoKUmV2aWV3ZWQtYnk6IEp1bndlaSBaaGFu ZyA8SmVycnkuWmhhbmdAYW1kLmNvbT4KCkplcnJ5Cj4gLS0tCj4gICBkcml2ZXJzL2RtYS1idWYv ZG1hLWJ1Zi5jIHwgOSArKysrKystLS0KPiAgIGluY2x1ZGUvbGludXgvZG1hLWJ1Zi5oICAgfCA0 ICsrKysKPiAgIDIgZmlsZXMgY2hhbmdlZCwgMTAgaW5zZXJ0aW9ucygrKSwgMyBkZWxldGlvbnMo LSkKPgo+IGRpZmYgLS1naXQgYS9kcml2ZXJzL2RtYS1idWYvZG1hLWJ1Zi5jIGIvZHJpdmVycy9k bWEtYnVmL2RtYS1idWYuYwo+IGluZGV4IGRjOTRlNzZlMmUyYS4uNDlmMjNiNzkxZWI4IDEwMDY0 NAo+IC0tLSBhL2RyaXZlcnMvZG1hLWJ1Zi9kbWEtYnVmLmMKPiArKysgYi9kcml2ZXJzL2RtYS1i dWYvZG1hLWJ1Zi5jCj4gQEAgLTY2NSw3ICs2NjUsOSBAQCBzdHJ1Y3Qgc2dfdGFibGUgKmRtYV9i dWZfbWFwX2F0dGFjaG1lbnQoc3RydWN0IGRtYV9idWZfYXR0YWNobWVudCAqYXR0YWNoLAo+ICAg CWlmIChXQVJOX09OKCFhdHRhY2ggfHwgIWF0dGFjaC0+ZG1hYnVmKSkKPiAgIAkJcmV0dXJuIEVS Ul9QVFIoLUVJTlZBTCk7Cj4KPiAtCXNnX3RhYmxlID0gYXR0YWNoLT5kbWFidWYtPm9wcy0+bWFw X2RtYV9idWYoYXR0YWNoLCBkaXJlY3Rpb24pOwo+ICsJcmVzZXJ2YXRpb25fb2JqZWN0X2xvY2so YXR0YWNoLT5kbWFidWYtPnJlc3YsIE5VTEwpOwo+ICsJc2dfdGFibGUgPSBkbWFfYnVmX21hcF9h dHRhY2htZW50X2xvY2tlZChhdHRhY2gsIGRpcmVjdGlvbik7Cj4gKwlyZXNlcnZhdGlvbl9vYmpl Y3RfdW5sb2NrKGF0dGFjaC0+ZG1hYnVmLT5yZXN2KTsKPiAgIAlpZiAoIXNnX3RhYmxlKQo+ICAg CQlzZ190YWJsZSA9IEVSUl9QVFIoLUVOT01FTSk7Cj4KPiBAQCAtNzE1LDggKzcxNyw5IEBAIHZv aWQgZG1hX2J1Zl91bm1hcF9hdHRhY2htZW50KHN0cnVjdCBkbWFfYnVmX2F0dGFjaG1lbnQgKmF0 dGFjaCwKPiAgIAlpZiAoV0FSTl9PTighYXR0YWNoIHx8ICFhdHRhY2gtPmRtYWJ1ZiB8fCAhc2df dGFibGUpKQo+ICAgCQlyZXR1cm47Cj4KPiAtCWF0dGFjaC0+ZG1hYnVmLT5vcHMtPnVubWFwX2Rt YV9idWYoYXR0YWNoLCBzZ190YWJsZSwKPiAtCQkJCQkJZGlyZWN0aW9uKTsKPiArCXJlc2VydmF0 aW9uX29iamVjdF9sb2NrKGF0dGFjaC0+ZG1hYnVmLT5yZXN2LCBOVUxMKTsKPiArCWRtYV9idWZf dW5tYXBfYXR0YWNobWVudF9sb2NrZWQoYXR0YWNoLCBzZ190YWJsZSwgZGlyZWN0aW9uKTsKPiAr CXJlc2VydmF0aW9uX29iamVjdF91bmxvY2soYXR0YWNoLT5kbWFidWYtPnJlc3YpOwo+ICAgfQo+ ICAgRVhQT1JUX1NZTUJPTF9HUEwoZG1hX2J1Zl91bm1hcF9hdHRhY2htZW50KTsKPgo+IGRpZmYg LS1naXQgYS9pbmNsdWRlL2xpbnV4L2RtYS1idWYuaCBiL2luY2x1ZGUvbGludXgvZG1hLWJ1Zi5o Cj4gaW5kZXggYTI1ZTc1NGFlMmY3Li4wMjQ2NThkMWYyMmUgMTAwNjQ0Cj4gLS0tIGEvaW5jbHVk ZS9saW51eC9kbWEtYnVmLmgKPiArKysgYi9pbmNsdWRlL2xpbnV4L2RtYS1idWYuaAo+IEBAIC0x MTgsNiArMTE4LDggQEAgc3RydWN0IGRtYV9idWZfb3BzIHsKPiAgIAkgKiBhbnkgb3RoZXIga2lu ZCBvZiBzaGFyaW5nIHRoYXQgdGhlIGV4cG9ydGVyIG1pZ2h0IHdpc2ggdG8gbWFrZQo+ICAgCSAq IGF2YWlsYWJsZSB0byBidWZmZXItdXNlcnMuCj4gICAJICoKPiArCSAqIFRoaXMgaXMgY2FsbGVk IHdpdGggdGhlIGRtYWJ1Zi0+cmVzdiBvYmplY3QgbG9ja2VkLgo+ICsJICoKPiAgIAkgKiBSZXR1 cm5zOgo+ICAgCSAqCj4gICAJICogQSAmc2dfdGFibGUgc2NhdHRlciBsaXN0IG9mIG9yIHRoZSBi YWNraW5nIHN0b3JhZ2Ugb2YgdGhlIERNQSBidWZmZXIsCj4gQEAgLTEzOCw2ICsxNDAsOCBAQCBz dHJ1Y3QgZG1hX2J1Zl9vcHMgewo+ICAgCSAqIEl0IHNob3VsZCBhbHNvIHVucGluIHRoZSBiYWNr aW5nIHN0b3JhZ2UgaWYgdGhpcyBpcyB0aGUgbGFzdCBtYXBwaW5nCj4gICAJICogb2YgdGhlIERN QSBidWZmZXIsIGl0IHRoZSBleHBvcnRlciBzdXBwb3J0cyBiYWNraW5nIHN0b3JhZ2UKPiAgIAkg KiBtaWdyYXRpb24uCj4gKwkgKgo+ICsJICogVGhpcyBpcyBjYWxsZWQgd2l0aCB0aGUgZG1hYnVm LT5yZXN2IG9iamVjdCBsb2NrZWQuCj4gICAJICovCj4gICAJdm9pZCAoKnVubWFwX2RtYV9idWYp KHN0cnVjdCBkbWFfYnVmX2F0dGFjaG1lbnQgKiwKPiAgIAkJCSAgICAgIHN0cnVjdCBzZ190YWJs ZSAqLAo+Cl9fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fCmRy aS1kZXZlbCBtYWlsaW5nIGxpc3QKZHJpLWRldmVsQGxpc3RzLmZyZWVkZXNrdG9wLm9yZwpodHRw czovL2xpc3RzLmZyZWVkZXNrdG9wLm9yZy9tYWlsbWFuL2xpc3RpbmZvL2RyaS1kZXZlbAo= From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-eopbgr710059.outbound.protection.outlook.com ([40.107.71.59]:29872 "EHLO NAM05-BY2-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932809AbeF1JyG (ORCPT ); Thu, 28 Jun 2018 05:54:06 -0400 Message-ID: <5B34B037.50105@amd.com> Date: Thu, 28 Jun 2018 17:53:59 +0800 From: "Zhang, Jerry (Junwei)" MIME-Version: 1.0 To: =?UTF-8?B?Q2hyaXN0aWFuIEvDtm5pZw==?= , , , , , , Subject: Re: [PATCH 2/4] dma-buf: lock the reservation object during (un)map_dma_buf v2 References: <20180622141103.1787-1-christian.koenig@amd.com> <20180622141103.1787-3-christian.koenig@amd.com> In-Reply-To: <20180622141103.1787-3-christian.koenig@amd.com> Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 8bit Sender: linux-media-owner@vger.kernel.org List-ID: On 06/22/2018 10:11 PM, Christian König wrote: > First step towards unpinned DMA buf operation. > > I've checked the DRM drivers to potential locking of the reservation > object, but essentially we need to audit all implementations of the > dma_buf _ops for this to work. > > v2: reordered > > Signed-off-by: Christian König looks good for me. Reviewed-by: Junwei Zhang Jerry > --- > drivers/dma-buf/dma-buf.c | 9 ++++++--- > include/linux/dma-buf.h | 4 ++++ > 2 files changed, 10 insertions(+), 3 deletions(-) > > diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c > index dc94e76e2e2a..49f23b791eb8 100644 > --- a/drivers/dma-buf/dma-buf.c > +++ b/drivers/dma-buf/dma-buf.c > @@ -665,7 +665,9 @@ struct sg_table *dma_buf_map_attachment(struct dma_buf_attachment *attach, > if (WARN_ON(!attach || !attach->dmabuf)) > return ERR_PTR(-EINVAL); > > - sg_table = attach->dmabuf->ops->map_dma_buf(attach, direction); > + reservation_object_lock(attach->dmabuf->resv, NULL); > + sg_table = dma_buf_map_attachment_locked(attach, direction); > + reservation_object_unlock(attach->dmabuf->resv); > if (!sg_table) > sg_table = ERR_PTR(-ENOMEM); > > @@ -715,8 +717,9 @@ void dma_buf_unmap_attachment(struct dma_buf_attachment *attach, > if (WARN_ON(!attach || !attach->dmabuf || !sg_table)) > return; > > - attach->dmabuf->ops->unmap_dma_buf(attach, sg_table, > - direction); > + reservation_object_lock(attach->dmabuf->resv, NULL); > + dma_buf_unmap_attachment_locked(attach, sg_table, direction); > + reservation_object_unlock(attach->dmabuf->resv); > } > EXPORT_SYMBOL_GPL(dma_buf_unmap_attachment); > > diff --git a/include/linux/dma-buf.h b/include/linux/dma-buf.h > index a25e754ae2f7..024658d1f22e 100644 > --- a/include/linux/dma-buf.h > +++ b/include/linux/dma-buf.h > @@ -118,6 +118,8 @@ struct dma_buf_ops { > * any other kind of sharing that the exporter might wish to make > * available to buffer-users. > * > + * This is called with the dmabuf->resv object locked. > + * > * Returns: > * > * A &sg_table scatter list of or the backing storage of the DMA buffer, > @@ -138,6 +140,8 @@ struct dma_buf_ops { > * It should also unpin the backing storage if this is the last mapping > * of the DMA buffer, it the exporter supports backing storage > * migration. > + * > + * This is called with the dmabuf->resv object locked. > */ > void (*unmap_dma_buf)(struct dma_buf_attachment *, > struct sg_table *, >