| Message ID | 20240912045150.915573-2-xu.yang_2@nxp.com |
|---|---|
| State | New |
| Headers | show |
| Series | [1/2] usb: chipidea: udc: limit usb request length to max 16KB | expand |
On 24-09-12 12:51:50, Xu Yang wrote: > The chipidea controller doesn't fully support sglist, such as it can not > transfer data spanned more dTDs to form a bus packet, so it can only work > on very limited cases. > > The limitations as below: > 1. the end address of the first sg buffer must be 4KB aligned. > 2. the start and end address of the middle sg buffer must be 4KB aligned. > 3. the start address of the first sg buffer must be 4KB aligned. > > However, not all the use cases violate these limitations. To make the > controller compatible with most of the cases, this will try to bounce the > problem sglist entries which can be found by sglist_get_invalid_entry(). > Then a bounced line buffer (the size will roundup to page size) will be > allocated to replace the remaining problem sg entries. The data will be > copied between problem sg entries and bounce buffer according to the > transfer direction. The bounce buffer will be freed when the request > completed. > > Signed-off-by: Xu Yang <xu.yang_2@nxp.com> Acked-by: Peter Chen <peter.chen@kernel.com> > --- > drivers/usb/chipidea/udc.c | 147 +++++++++++++++++++++++++++++++++++++ > drivers/usb/chipidea/udc.h | 2 + > 2 files changed, 149 insertions(+) > > diff --git a/drivers/usb/chipidea/udc.c b/drivers/usb/chipidea/udc.c > index 5d9369d01065..dc4dae2c31b4 100644 > --- a/drivers/usb/chipidea/udc.c > +++ b/drivers/usb/chipidea/udc.c > @@ -10,6 +10,7 @@ > #include <linux/delay.h> > #include <linux/device.h> > #include <linux/dmapool.h> > +#include <linux/dma-direct.h> > #include <linux/err.h> > #include <linux/irqreturn.h> > #include <linux/kernel.h> > @@ -540,6 +541,126 @@ static int prepare_td_for_sg(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq) > return ret; > } > > +/* > + * Verify if the scatterlist is valid by iterating each sg entry. > + * Return invalid sg entry index which is less than num_sgs. > + */ > +static int sglist_get_invalid_entry(struct device *dma_dev, u8 dir, > + struct usb_request *req) > +{ > + int i; > + struct scatterlist *s = req->sg; > + > + if (req->num_sgs == 1) > + return 1; > + > + dir = dir ? DMA_TO_DEVICE : DMA_FROM_DEVICE; > + > + for (i = 0; i < req->num_sgs; i++, s = sg_next(s)) { > + /* Only small sg (generally last sg) may be bounced. If > + * that happens. we can't ensure the addr is page-aligned > + * after dma map. > + */ > + if (dma_kmalloc_needs_bounce(dma_dev, s->length, dir)) > + break; > + > + /* Make sure each sg start address (except first sg) is > + * page-aligned and end address (except last sg) is also > + * page-aligned. > + */ > + if (i == 0) { > + if (!IS_ALIGNED(s->offset + s->length, > + CI_HDRC_PAGE_SIZE)) > + break; > + } else { > + if (s->offset) > + break; > + if (!sg_is_last(s) && !IS_ALIGNED(s->length, > + CI_HDRC_PAGE_SIZE)) > + break; > + } > + } > + > + return i; > +} > + > +static int sglist_do_bounce(struct ci_hw_req *hwreq, int index, > + bool copy, unsigned int *bounced) > +{ > + void *buf; > + int i, ret, nents, num_sgs; > + unsigned int rest, rounded; > + struct scatterlist *sg, *src, *dst; > + > + nents = index + 1; > + ret = sg_alloc_table(&hwreq->sgt, nents, GFP_KERNEL); > + if (ret) > + return ret; > + > + sg = src = hwreq->req.sg; > + num_sgs = hwreq->req.num_sgs; > + rest = hwreq->req.length; > + dst = hwreq->sgt.sgl; > + > + for (i = 0; i < index; i++) { > + memcpy(dst, src, sizeof(*src)); > + rest -= src->length; > + src = sg_next(src); > + dst = sg_next(dst); > + } > + > + /* create one bounce buffer */ > + rounded = round_up(rest, CI_HDRC_PAGE_SIZE); > + buf = kmalloc(rounded, GFP_KERNEL); > + if (!buf) { > + sg_free_table(&hwreq->sgt); > + return -ENOMEM; > + } > + > + sg_set_buf(dst, buf, rounded); > + > + hwreq->req.sg = hwreq->sgt.sgl; > + hwreq->req.num_sgs = nents; > + hwreq->sgt.sgl = sg; > + hwreq->sgt.nents = num_sgs; > + > + if (copy) > + sg_copy_to_buffer(src, num_sgs - index, buf, rest); > + > + *bounced = rest; > + > + return 0; > +} > + > +static void sglist_do_debounce(struct ci_hw_req *hwreq, bool copy) > +{ > + void *buf; > + int i, nents, num_sgs; > + struct scatterlist *sg, *src, *dst; > + > + sg = hwreq->req.sg; > + num_sgs = hwreq->req.num_sgs; > + src = sg_last(sg, num_sgs); > + buf = sg_virt(src); > + > + if (copy) { > + dst = hwreq->sgt.sgl; > + for (i = 0; i < num_sgs - 1; i++) > + dst = sg_next(dst); > + > + nents = hwreq->sgt.nents - num_sgs + 1; > + sg_copy_from_buffer(dst, nents, buf, sg_dma_len(src)); > + } > + > + hwreq->req.sg = hwreq->sgt.sgl; > + hwreq->req.num_sgs = hwreq->sgt.nents; > + hwreq->sgt.sgl = sg; > + hwreq->sgt.nents = num_sgs; > + > + kfree(buf); > + sg_free_table(&hwreq->sgt); > +} > + > /** > * _hardware_enqueue: configures a request at hardware level > * @hwep: endpoint > @@ -552,6 +673,8 @@ static int _hardware_enqueue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq) > struct ci_hdrc *ci = hwep->ci; > int ret = 0; > struct td_node *firstnode, *lastnode; > + unsigned int bounced_size; > + struct scatterlist *sg; > > /* don't queue twice */ > if (hwreq->req.status == -EALREADY) > @@ -559,11 +682,28 @@ static int _hardware_enqueue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq) > > hwreq->req.status = -EALREADY; > > + if (hwreq->req.num_sgs && hwreq->req.length) { > + ret = sglist_get_invalid_entry(ci->dev->parent, hwep->dir, > + &hwreq->req); > + if (ret < hwreq->req.num_sgs) { > + ret = sglist_do_bounce(hwreq, ret, hwep->dir == TX, > + &bounced_size); > + if (ret) > + return ret; > + } > + } > + > ret = usb_gadget_map_request_by_dev(ci->dev->parent, > &hwreq->req, hwep->dir); > if (ret) > return ret; > > + if (hwreq->sgt.sgl) { > + /* We've mapped a bigger buffer, now recover the actual size */ > + sg = sg_last(hwreq->req.sg, hwreq->req.num_sgs); > + sg_dma_len(sg) = min(sg_dma_len(sg), bounced_size); > + } > + > if (hwreq->req.num_mapped_sgs) > ret = prepare_td_for_sg(hwep, hwreq); > else > @@ -742,6 +882,10 @@ static int _hardware_dequeue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq) > usb_gadget_unmap_request_by_dev(hwep->ci->dev->parent, > &hwreq->req, hwep->dir); > > + /* sglist bounced */ > + if (hwreq->sgt.sgl) > + sglist_do_debounce(hwreq, hwep->dir == RX); > + > hwreq->req.actual += actual; > > if (hwreq->req.status) > @@ -1588,6 +1732,9 @@ static int ep_dequeue(struct usb_ep *ep, struct usb_request *req) > > usb_gadget_unmap_request(&hwep->ci->gadget, req, hwep->dir); > > + if (hwreq->sgt.sgl) > + sglist_do_debounce(hwreq, false); > + > req->status = -ECONNRESET; > > if (hwreq->req.complete != NULL) { > diff --git a/drivers/usb/chipidea/udc.h b/drivers/usb/chipidea/udc.h > index 5193df1e18c7..c8a47389a46b 100644 > --- a/drivers/usb/chipidea/udc.h > +++ b/drivers/usb/chipidea/udc.h > @@ -69,11 +69,13 @@ struct td_node { > * @req: request structure for gadget drivers > * @queue: link to QH list > * @tds: link to TD list > + * @sgt: hold original sglist when bounce sglist > */ > struct ci_hw_req { > struct usb_request req; > struct list_head queue; > struct list_head tds; > + struct sg_table sgt; > }; > > #ifdef CONFIG_USB_CHIPIDEA_UDC > -- > 2.34.1 >
Hi Xu,
kernel test robot noticed the following build warnings:
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Xu-Yang/usb-chipidea-udc-create-bounce-buffer-for-problem-sglist-entries-if-possible/20240912-125251
base: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing
patch link: https://lore.kernel.org/r/20240912045150.915573-2-xu.yang_2%40nxp.com
patch subject: [PATCH 2/2] usb: chipidea: udc: create bounce buffer for problem sglist entries if possible
config: i386-randconfig-141-20240914 (https://download.01.org/0day-ci/archive/20240914/202409141707.TOsGfePE-lkp@intel.com/config)
compiler: gcc-12 (Debian 12.2.0-14) 12.2.0
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
| Closes: https://lore.kernel.org/r/202409141707.TOsGfePE-lkp@intel.com/
New smatch warnings:
drivers/usb/chipidea/udc.c:704 _hardware_enqueue() error: uninitialized symbol 'bounced_size'.
vim +/bounced_size +704 drivers/usb/chipidea/udc.c
8e22978c57087a drivers/usb/chipidea/udc.c Alexander Shishkin 2013-06-24 671 static int _hardware_enqueue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq)
aa69a8093ff985 drivers/usb/gadget/ci13xxx_udc.c David Lopo 2008-11-17 672 {
8e22978c57087a drivers/usb/chipidea/udc.c Alexander Shishkin 2013-06-24 673 struct ci_hdrc *ci = hwep->ci;
0e6ca1998e4c80 drivers/usb/gadget/ci13xxx_udc.c Pavankumar Kondeti 2011-02-18 674 int ret = 0;
cc9e6c495b0a37 drivers/usb/chipidea/udc.c Michael Grzeschik 2013-06-13 675 struct td_node *firstnode, *lastnode;
91db40933ca942 drivers/usb/chipidea/udc.c Xu Yang 2024-09-12 676 unsigned int bounced_size;
91db40933ca942 drivers/usb/chipidea/udc.c Xu Yang 2024-09-12 677 struct scatterlist *sg;
aa69a8093ff985 drivers/usb/gadget/ci13xxx_udc.c David Lopo 2008-11-17 678
aa69a8093ff985 drivers/usb/gadget/ci13xxx_udc.c David Lopo 2008-11-17 679 /* don't queue twice */
2dbc5c4c831418 drivers/usb/chipidea/udc.c Alexander Shishkin 2013-06-13 680 if (hwreq->req.status == -EALREADY)
aa69a8093ff985 drivers/usb/gadget/ci13xxx_udc.c David Lopo 2008-11-17 681 return -EALREADY;
aa69a8093ff985 drivers/usb/gadget/ci13xxx_udc.c David Lopo 2008-11-17 682
2dbc5c4c831418 drivers/usb/chipidea/udc.c Alexander Shishkin 2013-06-13 683 hwreq->req.status = -EALREADY;
aa69a8093ff985 drivers/usb/gadget/ci13xxx_udc.c David Lopo 2008-11-17 684
91db40933ca942 drivers/usb/chipidea/udc.c Xu Yang 2024-09-12 685 if (hwreq->req.num_sgs && hwreq->req.length) {
91db40933ca942 drivers/usb/chipidea/udc.c Xu Yang 2024-09-12 686 ret = sglist_get_invalid_entry(ci->dev->parent, hwep->dir,
91db40933ca942 drivers/usb/chipidea/udc.c Xu Yang 2024-09-12 687 &hwreq->req);
91db40933ca942 drivers/usb/chipidea/udc.c Xu Yang 2024-09-12 688 if (ret < hwreq->req.num_sgs) {
91db40933ca942 drivers/usb/chipidea/udc.c Xu Yang 2024-09-12 689 ret = sglist_do_bounce(hwreq, ret, hwep->dir == TX,
91db40933ca942 drivers/usb/chipidea/udc.c Xu Yang 2024-09-12 690 &bounced_size);
91db40933ca942 drivers/usb/chipidea/udc.c Xu Yang 2024-09-12 691 if (ret)
91db40933ca942 drivers/usb/chipidea/udc.c Xu Yang 2024-09-12 692 return ret;
91db40933ca942 drivers/usb/chipidea/udc.c Xu Yang 2024-09-12 693 }
91db40933ca942 drivers/usb/chipidea/udc.c Xu Yang 2024-09-12 694 }
bounced_size not initialized on else path
91db40933ca942 drivers/usb/chipidea/udc.c Xu Yang 2024-09-12 695
aeb78cda51005f drivers/usb/chipidea/udc.c Arnd Bergmann 2017-03-13 696 ret = usb_gadget_map_request_by_dev(ci->dev->parent,
aeb78cda51005f drivers/usb/chipidea/udc.c Arnd Bergmann 2017-03-13 697 &hwreq->req, hwep->dir);
5e0aa49ec61e88 drivers/usb/chipidea/udc.c Alexander Shishkin 2012-05-11 698 if (ret)
5e0aa49ec61e88 drivers/usb/chipidea/udc.c Alexander Shishkin 2012-05-11 699 return ret;
5e0aa49ec61e88 drivers/usb/chipidea/udc.c Alexander Shishkin 2012-05-11 700
91db40933ca942 drivers/usb/chipidea/udc.c Xu Yang 2024-09-12 701 if (hwreq->sgt.sgl) {
91db40933ca942 drivers/usb/chipidea/udc.c Xu Yang 2024-09-12 702 /* We've mapped a bigger buffer, now recover the actual size */
91db40933ca942 drivers/usb/chipidea/udc.c Xu Yang 2024-09-12 703 sg = sg_last(hwreq->req.sg, hwreq->req.num_sgs);
91db40933ca942 drivers/usb/chipidea/udc.c Xu Yang 2024-09-12 @704 sg_dma_len(sg) = min(sg_dma_len(sg), bounced_size);
^^^^^^^^^^^^
91db40933ca942 drivers/usb/chipidea/udc.c Xu Yang 2024-09-12 705 }
91db40933ca942 drivers/usb/chipidea/udc.c Xu Yang 2024-09-12 706
e48aa1eb443f80 drivers/usb/chipidea/udc.c Peter Chen 2020-02-21 707 if (hwreq->req.num_mapped_sgs)
e48aa1eb443f80 drivers/usb/chipidea/udc.c Peter Chen 2020-02-21 708 ret = prepare_td_for_sg(hwep, hwreq);
e48aa1eb443f80 drivers/usb/chipidea/udc.c Peter Chen 2020-02-21 709 else
diff --git a/drivers/usb/chipidea/udc.c b/drivers/usb/chipidea/udc.c index 5d9369d01065..dc4dae2c31b4 100644 --- a/drivers/usb/chipidea/udc.c +++ b/drivers/usb/chipidea/udc.c @@ -10,6 +10,7 @@ #include <linux/delay.h> #include <linux/device.h> #include <linux/dmapool.h> +#include <linux/dma-direct.h> #include <linux/err.h> #include <linux/irqreturn.h> #include <linux/kernel.h> @@ -540,6 +541,126 @@ static int prepare_td_for_sg(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq) return ret; } +/* + * Verify if the scatterlist is valid by iterating each sg entry. + * Return invalid sg entry index which is less than num_sgs. + */ +static int sglist_get_invalid_entry(struct device *dma_dev, u8 dir, + struct usb_request *req) +{ + int i; + struct scatterlist *s = req->sg; + + if (req->num_sgs == 1) + return 1; + + dir = dir ? DMA_TO_DEVICE : DMA_FROM_DEVICE; + + for (i = 0; i < req->num_sgs; i++, s = sg_next(s)) { + /* Only small sg (generally last sg) may be bounced. If + * that happens. we can't ensure the addr is page-aligned + * after dma map. + */ + if (dma_kmalloc_needs_bounce(dma_dev, s->length, dir)) + break; + + /* Make sure each sg start address (except first sg) is + * page-aligned and end address (except last sg) is also + * page-aligned. + */ + if (i == 0) { + if (!IS_ALIGNED(s->offset + s->length, + CI_HDRC_PAGE_SIZE)) + break; + } else { + if (s->offset) + break; + if (!sg_is_last(s) && !IS_ALIGNED(s->length, + CI_HDRC_PAGE_SIZE)) + break; + } + } + + return i; +} + +static int sglist_do_bounce(struct ci_hw_req *hwreq, int index, + bool copy, unsigned int *bounced) +{ + void *buf; + int i, ret, nents, num_sgs; + unsigned int rest, rounded; + struct scatterlist *sg, *src, *dst; + + nents = index + 1; + ret = sg_alloc_table(&hwreq->sgt, nents, GFP_KERNEL); + if (ret) + return ret; + + sg = src = hwreq->req.sg; + num_sgs = hwreq->req.num_sgs; + rest = hwreq->req.length; + dst = hwreq->sgt.sgl; + + for (i = 0; i < index; i++) { + memcpy(dst, src, sizeof(*src)); + rest -= src->length; + src = sg_next(src); + dst = sg_next(dst); + } + + /* create one bounce buffer */ + rounded = round_up(rest, CI_HDRC_PAGE_SIZE); + buf = kmalloc(rounded, GFP_KERNEL); + if (!buf) { + sg_free_table(&hwreq->sgt); + return -ENOMEM; + } + + sg_set_buf(dst, buf, rounded); + + hwreq->req.sg = hwreq->sgt.sgl; + hwreq->req.num_sgs = nents; + hwreq->sgt.sgl = sg; + hwreq->sgt.nents = num_sgs; + + if (copy) + sg_copy_to_buffer(src, num_sgs - index, buf, rest); + + *bounced = rest; + + return 0; +} + +static void sglist_do_debounce(struct ci_hw_req *hwreq, bool copy) +{ + void *buf; + int i, nents, num_sgs; + struct scatterlist *sg, *src, *dst; + + sg = hwreq->req.sg; + num_sgs = hwreq->req.num_sgs; + src = sg_last(sg, num_sgs); + buf = sg_virt(src); + + if (copy) { + dst = hwreq->sgt.sgl; + for (i = 0; i < num_sgs - 1; i++) + dst = sg_next(dst); + + nents = hwreq->sgt.nents - num_sgs + 1; + sg_copy_from_buffer(dst, nents, buf, sg_dma_len(src)); + } + + hwreq->req.sg = hwreq->sgt.sgl; + hwreq->req.num_sgs = hwreq->sgt.nents; + hwreq->sgt.sgl = sg; + hwreq->sgt.nents = num_sgs; + + kfree(buf); + sg_free_table(&hwreq->sgt); +} + /** * _hardware_enqueue: configures a request at hardware level * @hwep: endpoint @@ -552,6 +673,8 @@ static int _hardware_enqueue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq) struct ci_hdrc *ci = hwep->ci; int ret = 0; struct td_node *firstnode, *lastnode; + unsigned int bounced_size; + struct scatterlist *sg; /* don't queue twice */ if (hwreq->req.status == -EALREADY) @@ -559,11 +682,28 @@ static int _hardware_enqueue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq) hwreq->req.status = -EALREADY; + if (hwreq->req.num_sgs && hwreq->req.length) { + ret = sglist_get_invalid_entry(ci->dev->parent, hwep->dir, + &hwreq->req); + if (ret < hwreq->req.num_sgs) { + ret = sglist_do_bounce(hwreq, ret, hwep->dir == TX, + &bounced_size); + if (ret) + return ret; + } + } + ret = usb_gadget_map_request_by_dev(ci->dev->parent, &hwreq->req, hwep->dir); if (ret) return ret; + if (hwreq->sgt.sgl) { + /* We've mapped a bigger buffer, now recover the actual size */ + sg = sg_last(hwreq->req.sg, hwreq->req.num_sgs); + sg_dma_len(sg) = min(sg_dma_len(sg), bounced_size); + } + if (hwreq->req.num_mapped_sgs) ret = prepare_td_for_sg(hwep, hwreq); else @@ -742,6 +882,10 @@ static int _hardware_dequeue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq) usb_gadget_unmap_request_by_dev(hwep->ci->dev->parent, &hwreq->req, hwep->dir); + /* sglist bounced */ + if (hwreq->sgt.sgl) + sglist_do_debounce(hwreq, hwep->dir == RX); + hwreq->req.actual += actual; if (hwreq->req.status) @@ -1588,6 +1732,9 @@ static int ep_dequeue(struct usb_ep *ep, struct usb_request *req) usb_gadget_unmap_request(&hwep->ci->gadget, req, hwep->dir); + if (hwreq->sgt.sgl) + sglist_do_debounce(hwreq, false); + req->status = -ECONNRESET; if (hwreq->req.complete != NULL) { diff --git a/drivers/usb/chipidea/udc.h b/drivers/usb/chipidea/udc.h index 5193df1e18c7..c8a47389a46b 100644 --- a/drivers/usb/chipidea/udc.h +++ b/drivers/usb/chipidea/udc.h @@ -69,11 +69,13 @@ struct td_node { * @req: request structure for gadget drivers * @queue: link to QH list * @tds: link to TD list + * @sgt: hold original sglist when bounce sglist */ struct ci_hw_req { struct usb_request req; struct list_head queue; struct list_head tds; + struct sg_table sgt; }; #ifdef CONFIG_USB_CHIPIDEA_UDC
The chipidea controller doesn't fully support sglist, such as it can not transfer data spanned more dTDs to form a bus packet, so it can only work on very limited cases. The limitations as below: 1. the end address of the first sg buffer must be 4KB aligned. 2. the start and end address of the middle sg buffer must be 4KB aligned. 3. the start address of the first sg buffer must be 4KB aligned. However, not all the use cases violate these limitations. To make the controller compatible with most of the cases, this will try to bounce the problem sglist entries which can be found by sglist_get_invalid_entry(). Then a bounced line buffer (the size will roundup to page size) will be allocated to replace the remaining problem sg entries. The data will be copied between problem sg entries and bounce buffer according to the transfer direction. The bounce buffer will be freed when the request completed. Signed-off-by: Xu Yang <xu.yang_2@nxp.com> --- drivers/usb/chipidea/udc.c | 147 +++++++++++++++++++++++++++++++++++++ drivers/usb/chipidea/udc.h | 2 + 2 files changed, 149 insertions(+)