| Message ID | 20250220131451.6f356f31@foxbook (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | None | expand |
On 20/02/2025 14.14, Michał Pecio wrote: > Here's my attempt at it, the patch goes on top of the whole series. It > compiles and passes basic testing (some URBs completed, some unlinked, > no errors or other malfunction apparent). > > The idea is to translate dma to trb* ASAP and work with that, because > all data structures use trb* so the code gets shorter and less verbose. > This approach is also easy to adapt to changes in handle_tx_event(), > for example it could trivially return trb* instead of seg* or take trb* > (with or without accompanying seg*) and return bool or even seg*. > > I tried to make the common case (start_seg == end_seg) fast, both for > hit and miss. 5 comparisons if the range wraps around, 4 if it doesn't. > Thanks, I have a similar version. If it's alright with you, I'll try to combine your version and mine into one and add it to trb_in_td-v2. Thanks, Niklas > diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c > index 600842425f6d..b18e7fd7d01e 100644 > --- a/drivers/usb/host/xhci-ring.c > +++ b/drivers/usb/host/xhci-ring.c > @@ -300,42 +300,36 @@ static struct xhci_segment *dma_in_range(struct xhci_segment *start_seg, union x > dma_addr_t dma) > { > struct xhci_segment *seg = start_seg; > + union xhci_trb *trb; > > - if (start_seg == end_seg) { > - if (start_trb <= end_trb) { > - if (xhci_trb_virt_to_dma(start_seg, start_trb) <= dma && > - dma <= xhci_trb_virt_to_dma(end_seg, end_trb)) > - return seg; > - return NULL; > + /* check if dma is a TRB in start_seg */ > + if (in_range(dma, seg->dma, TRB_SEGMENT_SIZE)) { > + trb = seg->trbs + (dma - seg->dma) / sizeof(*trb); > + > + if (trb >= start_trb) > + /* check if the range covers it and we are done */ > + return (end_seg != seg || trb <= end_trb) ? seg : NULL; > + > + /* check if the range circles back to the beginning of start_seg */ > + return (end_seg == seg && end_trb < start_trb && trb <= end_trb) ? seg : NULL; > + } > + > + /* stop if the range doesn't pass through any other segment */ > + if (end_seg == seg && (end_trb >= start_trb || seg->next == seg)) > + return NULL; > + > + /* search remaining segments knowing that start_trb isn't there */ > + do { > + seg = seg->next; > + > + if (in_range(dma, seg->dma, TRB_SEGMENT_SIZE)) { > + trb = seg->trbs + (dma - seg->dma) / sizeof(*trb); > + > + return (seg != end_seg || trb <= end_trb) ? seg : NULL; > } > + } while (seg != end_seg && seg != start_seg); > > - /* Edge case, the TD wrapped around to the start segment. */ > - if (xhci_trb_virt_to_dma(end_seg, end_trb) < dma && > - dma < xhci_trb_virt_to_dma(start_seg, start_trb)) > - return NULL; > - if (seg->dma <= dma && dma <= (seg->dma + TRB_SEGMENT_SIZE)) > - return seg; > - seg = seg->next; > - } > - > - /* Loop through segment which don't contain the DMA address. */ > - while (dma < seg->dma || (seg->dma + TRB_SEGMENT_SIZE) <= dma) { > - if (seg == end_seg) > - return NULL; > - > - seg = seg->next; > - if (seg == start_seg) > - return NULL; > - } > - > - if (seg == start_seg) { > - if (dma < xhci_trb_virt_to_dma(start_seg, start_trb)) > - return NULL; > - } else if (seg == end_seg) { > - if (xhci_trb_virt_to_dma(end_seg, end_trb) < dma) > - return NULL; > - } > - return seg; > + return NULL; > } > > static struct xhci_segment *trb_in_td(struct xhci_td *td, dma_addr_t dma)
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index 600842425f6d..b18e7fd7d01e 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -300,42 +300,36 @@ static struct xhci_segment *dma_in_range(struct xhci_segment *start_seg, union x dma_addr_t dma) { struct xhci_segment *seg = start_seg; + union xhci_trb *trb; - if (start_seg == end_seg) { - if (start_trb <= end_trb) { - if (xhci_trb_virt_to_dma(start_seg, start_trb) <= dma && - dma <= xhci_trb_virt_to_dma(end_seg, end_trb)) - return seg; - return NULL; + /* check if dma is a TRB in start_seg */ + if (in_range(dma, seg->dma, TRB_SEGMENT_SIZE)) { + trb = seg->trbs + (dma - seg->dma) / sizeof(*trb); + + if (trb >= start_trb) + /* check if the range covers it and we are done */ + return (end_seg != seg || trb <= end_trb) ? seg : NULL; + + /* check if the range circles back to the beginning of start_seg */ + return (end_seg == seg && end_trb < start_trb && trb <= end_trb) ? seg : NULL; + } + + /* stop if the range doesn't pass through any other segment */ + if (end_seg == seg && (end_trb >= start_trb || seg->next == seg)) + return NULL; + + /* search remaining segments knowing that start_trb isn't there */ + do { + seg = seg->next; + + if (in_range(dma, seg->dma, TRB_SEGMENT_SIZE)) { + trb = seg->trbs + (dma - seg->dma) / sizeof(*trb); + + return (seg != end_seg || trb <= end_trb) ? seg : NULL; } + } while (seg != end_seg && seg != start_seg); - /* Edge case, the TD wrapped around to the start segment. */ - if (xhci_trb_virt_to_dma(end_seg, end_trb) < dma && - dma < xhci_trb_virt_to_dma(start_seg, start_trb)) - return NULL; - if (seg->dma <= dma && dma <= (seg->dma + TRB_SEGMENT_SIZE)) - return seg; - seg = seg->next; - } - - /* Loop through segment which don't contain the DMA address. */ - while (dma < seg->dma || (seg->dma + TRB_SEGMENT_SIZE) <= dma) { - if (seg == end_seg) - return NULL; - - seg = seg->next; - if (seg == start_seg) - return NULL; - } - - if (seg == start_seg) { - if (dma < xhci_trb_virt_to_dma(start_seg, start_trb)) - return NULL; - } else if (seg == end_seg) { - if (xhci_trb_virt_to_dma(end_seg, end_trb) < dma) - return NULL; - } - return seg; + return NULL; } static struct xhci_segment *trb_in_td(struct xhci_td *td, dma_addr_t dma)