From: Laurentiu Tudor Date: Wed, 29 May 2019 13:28:40 +0300 Subject: USB: use genalloc for USB HCs with local memory Origin: https://git.kernel.org/linus/b0310c2f09bbe8aebefb97ed67949a3a7092aca6 For HCs that have local memory, replace the current DMA API usage with a genalloc generic allocator to manage the mappings for these devices. To help users, introduce a new HCD API, usb_hcd_setup_local_mem() that will setup up the genalloc backing up the device local memory. It will be used in subsequent patches. This is in preparation for dropping the existing "coherent" dma mem declaration APIs. The current implementation was relying on a short circuit in the DMA API that in the end, was acting as an allocator for these type of devices. Signed-off-by: Laurentiu Tudor Tested-by: Fredrik Noring Reviewed-by: Greg Kroah-Hartman Signed-off-by: Christoph Hellwig --- drivers/usb/Kconfig | 1 + drivers/usb/core/buffer.c | 9 +++++++++ drivers/usb/core/hcd.c | 36 ++++++++++++++++++++++++++++++++++++ drivers/usb/host/ohci-hcd.c | 23 ++++++++++++++++++----- drivers/usb/host/ohci-mem.c | 35 +++++++++++++++++++++++++++++++---- drivers/usb/host/ohci.h | 2 ++ include/linux/usb/hcd.h | 5 +++++ 7 files changed, 102 insertions(+), 9 deletions(-) --- a/drivers/usb/Kconfig +++ b/drivers/usb/Kconfig @@ -44,6 +44,7 @@ config USB tristate "Support for Host-side USB" depends on USB_ARCH_HAS_HCD + select GENERIC_ALLOCATOR select USB_COMMON select NLS # for UTF-8 strings ---help--- --- a/drivers/usb/core/buffer.c +++ b/drivers/usb/core/buffer.c @@ -16,6 +16,7 @@ #include #include #include +#include #include #include @@ -128,6 +129,9 @@ if (size == 0) return NULL; + if (hcd->localmem_pool) + return gen_pool_dma_alloc(hcd->localmem_pool, size, dma); + /* some USB hosts just use PIO */ if (!IS_ENABLED(CONFIG_HAS_DMA) || (!is_device_dma_capable(bus->sysdev) && @@ -156,6 +160,11 @@ if (!addr) return; + if (hcd->localmem_pool) { + gen_pool_free(hcd->localmem_pool, (unsigned long)addr, size); + return; + } + if (!IS_ENABLED(CONFIG_HAS_DMA) || (!is_device_dma_capable(bus->sysdev) && !(hcd->driver->flags & HCD_LOCAL_MEM))) { --- a/drivers/usb/core/hcd.c +++ b/drivers/usb/core/hcd.c @@ -29,6 +29,8 @@ #include #include #include +#include +#include #include #include @@ -3025,6 +3027,40 @@ } EXPORT_SYMBOL_GPL(usb_hcd_platform_shutdown); +int usb_hcd_setup_local_mem(struct usb_hcd *hcd, phys_addr_t phys_addr, + dma_addr_t dma, size_t size) +{ + int err; + void *local_mem; + + hcd->localmem_pool = devm_gen_pool_create(hcd->self.sysdev, PAGE_SHIFT, + dev_to_node(hcd->self.sysdev), + dev_name(hcd->self.sysdev)); + if (IS_ERR(hcd->localmem_pool)) + return PTR_ERR(hcd->localmem_pool); + + local_mem = devm_memremap(hcd->self.sysdev, phys_addr, + size, MEMREMAP_WC); + if (!local_mem) + return -ENOMEM; + + /* + * Here we pass a dma_addr_t but the arg type is a phys_addr_t. + * It's not backed by system memory and thus there's no kernel mapping + * for it. + */ + err = gen_pool_add_virt(hcd->localmem_pool, (unsigned long)local_mem, + dma, size, dev_to_node(hcd->self.sysdev)); + if (err < 0) { + dev_err(hcd->self.sysdev, "gen_pool_add_virt failed with %d\n", + err); + return err; + } + + return 0; +} +EXPORT_SYMBOL_GPL(usb_hcd_setup_local_mem); + /*-------------------------------------------------------------------------*/ #if IS_ENABLED(CONFIG_USB_MON) --- a/drivers/usb/host/ohci-hcd.c +++ b/drivers/usb/host/ohci-hcd.c @@ -40,6 +40,7 @@ #include #include #include +#include #include #include @@ -514,8 +515,15 @@ timer_setup(&ohci->io_watchdog, io_watchdog_func, 0); ohci->prev_frame_no = IO_WATCHDOG_OFF; - ohci->hcca = dma_alloc_coherent (hcd->self.controller, - sizeof(*ohci->hcca), &ohci->hcca_dma, GFP_KERNEL); + if (hcd->localmem_pool) + ohci->hcca = gen_pool_dma_alloc(hcd->localmem_pool, + sizeof(*ohci->hcca), + &ohci->hcca_dma); + else + ohci->hcca = dma_alloc_coherent(hcd->self.controller, + sizeof(*ohci->hcca), + &ohci->hcca_dma, + GFP_KERNEL); if (!ohci->hcca) return -ENOMEM; @@ -999,9 +1007,14 @@ remove_debug_files (ohci); ohci_mem_cleanup (ohci); if (ohci->hcca) { - dma_free_coherent (hcd->self.controller, - sizeof *ohci->hcca, - ohci->hcca, ohci->hcca_dma); + if (hcd->localmem_pool) + gen_pool_free(hcd->localmem_pool, + (unsigned long)ohci->hcca, + sizeof(*ohci->hcca)); + else + dma_free_coherent(hcd->self.controller, + sizeof(*ohci->hcca), + ohci->hcca, ohci->hcca_dma); ohci->hcca = NULL; ohci->hcca_dma = 0; } --- a/drivers/usb/host/ohci-mem.c +++ b/drivers/usb/host/ohci-mem.c @@ -36,6 +36,13 @@ static int ohci_mem_init (struct ohci_hcd *ohci) { + /* + * HCs with local memory allocate from localmem_pool so there's + * no need to create the below dma pools. + */ + if (ohci_to_hcd(ohci)->localmem_pool) + return 0; + ohci->td_cache = dma_pool_create ("ohci_td", ohci_to_hcd(ohci)->self.controller, sizeof (struct td), @@ -88,8 +95,12 @@ { dma_addr_t dma; struct td *td; + struct usb_hcd *hcd = ohci_to_hcd(hc); - td = dma_pool_zalloc (hc->td_cache, mem_flags, &dma); + if (hcd->localmem_pool) + td = gen_pool_dma_zalloc(hcd->localmem_pool, sizeof(*td), &dma); + else + td = dma_pool_zalloc(hc->td_cache, mem_flags, &dma); if (td) { /* in case hc fetches it, make it look dead */ td->hwNextTD = cpu_to_hc32 (hc, dma); @@ -103,6 +114,7 @@ td_free (struct ohci_hcd *hc, struct td *td) { struct td **prev = &hc->td_hash [TD_HASH_FUNC (td->td_dma)]; + struct usb_hcd *hcd = ohci_to_hcd(hc); while (*prev && *prev != td) prev = &(*prev)->td_hash; @@ -110,7 +122,12 @@ *prev = td->td_hash; else if ((td->hwINFO & cpu_to_hc32(hc, TD_DONE)) != 0) ohci_dbg (hc, "no hash for td %p\n", td); - dma_pool_free (hc->td_cache, td, td->td_dma); + + if (hcd->localmem_pool) + gen_pool_free(hcd->localmem_pool, (unsigned long)td, + sizeof(*td)); + else + dma_pool_free(hc->td_cache, td, td->td_dma); } /*-------------------------------------------------------------------------*/ @@ -121,8 +138,12 @@ { dma_addr_t dma; struct ed *ed; + struct usb_hcd *hcd = ohci_to_hcd(hc); - ed = dma_pool_zalloc (hc->ed_cache, mem_flags, &dma); + if (hcd->localmem_pool) + ed = gen_pool_dma_zalloc(hcd->localmem_pool, sizeof(*ed), &dma); + else + ed = dma_pool_zalloc(hc->ed_cache, mem_flags, &dma); if (ed) { INIT_LIST_HEAD (&ed->td_list); ed->dma = dma; @@ -133,6 +154,12 @@ static void ed_free (struct ohci_hcd *hc, struct ed *ed) { - dma_pool_free (hc->ed_cache, ed, ed->dma); + struct usb_hcd *hcd = ohci_to_hcd(hc); + + if (hcd->localmem_pool) + gen_pool_free(hcd->localmem_pool, (unsigned long)ed, + sizeof(*ed)); + else + dma_pool_free(hc->ed_cache, ed, ed->dma); } --- a/drivers/usb/host/ohci.h +++ b/drivers/usb/host/ohci.h @@ -385,6 +385,8 @@ /* * memory management for queue data structures + * + * @td_cache and @ed_cache are %NULL if &usb_hcd.localmem_pool is used. */ struct dma_pool *td_cache; struct dma_pool *ed_cache; --- a/include/linux/usb/hcd.h +++ b/include/linux/usb/hcd.h @@ -211,6 +211,9 @@ #define HC_IS_RUNNING(state) ((state) & __ACTIVE) #define HC_IS_SUSPENDED(state) ((state) & __SUSPEND) + /* memory pool for HCs having local memory, or %NULL */ + struct gen_pool *localmem_pool; + /* more shared queuing code would be good; it should support * smarter scheduling, handle transaction translators, etc; * input size of periodic table to an interrupt scheduler. @@ -461,6 +464,8 @@ unsigned int irqnum, unsigned long irqflags); extern void usb_remove_hcd(struct usb_hcd *hcd); extern int usb_hcd_find_raw_port_number(struct usb_hcd *hcd, int port1); +int usb_hcd_setup_local_mem(struct usb_hcd *hcd, phys_addr_t phys_addr, + dma_addr_t dma, size_t size); struct platform_device; extern void usb_hcd_platform_shutdown(struct platform_device *dev);