On Tue, Jun 25, 2019 at 05:08:23PM +0200, Fredrik Noring wrote: > The PAGE_SHIFT alignment restriction to devm_gen_pool_create() quickly > exhaust local memory because most allocations are much smaller than > PAGE_SIZE. This causes USB device failures such as > > usb 1-2.1: reset full-speed USB device number 4 using sm501-usb > sd 1:0:0:0: [sda] tag#0 UNKNOWN(0x2003) Result: hostbyte=0x03 > driverbyte=0x00 > sd 1:0:0:0: [sda] tag#0 CDB: opcode=0x28 28 00 00 00 08 7c 00 00 f0 00 > print_req_error: I/O error, dev sda, sector 2172 flags 80700 > > when trying to boot from the SM501 USB controller on SH4 with QEMU. > > Align allocations as required but not necessarily much more than that. > The HCCA, TD and ED structures align with 256, 32 and 16 byte memory > boundaries, as specified by the Open HCI[1]. The min_alloc_order argument > to devm_gen_pool_create is now somewhat arbitrarily set to 4 (16 bytes). > Perhaps it could be somewhat lower for general buffer allocations. > > Reference: > > [1] "Open Host Controller Interface Specification for USB", > release 1.0a, Compaq, Microsoft, National Semiconductor, 1999, > pp. 16, 19, 33. > > Reported-by: Guenter Roeck <[email protected]> > Signed-off-by: Fredrik Noring <[email protected]>
Tested-by: Guenter Roeck <[email protected]> > --- > drivers/usb/core/hcd.c | 2 +- > drivers/usb/host/ohci-hcd.c | 4 ++-- > drivers/usb/host/ohci-mem.c | 6 ++++-- > 3 files changed, 7 insertions(+), 5 deletions(-) > > diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c > index b2362303d32f..48483fa71854 100644 > --- a/drivers/usb/core/hcd.c > +++ b/drivers/usb/core/hcd.c > @@ -3014,7 +3014,7 @@ int usb_hcd_setup_local_mem(struct usb_hcd *hcd, > phys_addr_t phys_addr, > int err; > void __iomem *local_mem; > > - hcd->localmem_pool = devm_gen_pool_create(hcd->self.sysdev, PAGE_SHIFT, > + hcd->localmem_pool = devm_gen_pool_create(hcd->self.sysdev, 4, > dev_to_node(hcd->self.sysdev), > dev_name(hcd->self.sysdev)); > if (IS_ERR(hcd->localmem_pool)) > diff --git a/drivers/usb/host/ohci-hcd.c b/drivers/usb/host/ohci-hcd.c > index 5801858d867e..b457fdaff297 100644 > --- a/drivers/usb/host/ohci-hcd.c > +++ b/drivers/usb/host/ohci-hcd.c > @@ -507,9 +507,9 @@ static int ohci_init (struct ohci_hcd *ohci) > ohci->prev_frame_no = IO_WATCHDOG_OFF; > > if (hcd->localmem_pool) > - ohci->hcca = gen_pool_dma_alloc(hcd->localmem_pool, > + ohci->hcca = gen_pool_dma_alloc_align(hcd->localmem_pool, > sizeof(*ohci->hcca), > - &ohci->hcca_dma); > + &ohci->hcca_dma, 256); > else > ohci->hcca = dma_alloc_coherent(hcd->self.controller, > sizeof(*ohci->hcca), > diff --git a/drivers/usb/host/ohci-mem.c b/drivers/usb/host/ohci-mem.c > index 4afe27cc7e46..1425335c6baf 100644 > --- a/drivers/usb/host/ohci-mem.c > +++ b/drivers/usb/host/ohci-mem.c > @@ -94,7 +94,8 @@ td_alloc (struct ohci_hcd *hc, gfp_t mem_flags) > struct usb_hcd *hcd = ohci_to_hcd(hc); > > if (hcd->localmem_pool) > - td = gen_pool_dma_zalloc(hcd->localmem_pool, sizeof(*td), &dma); > + td = gen_pool_dma_zalloc_align(hcd->localmem_pool, > + sizeof(*td), &dma, 32); > else > td = dma_pool_zalloc(hc->td_cache, mem_flags, &dma); > if (td) { > @@ -137,7 +138,8 @@ ed_alloc (struct ohci_hcd *hc, gfp_t mem_flags) > struct usb_hcd *hcd = ohci_to_hcd(hc); > > if (hcd->localmem_pool) > - ed = gen_pool_dma_zalloc(hcd->localmem_pool, sizeof(*ed), &dma); > + ed = gen_pool_dma_zalloc_align(hcd->localmem_pool, > + sizeof(*ed), &dma, 16); > else > ed = dma_pool_zalloc(hc->ed_cache, mem_flags, &dma); > if (ed) { > -- > 2.21.0 >
