From fcea424d31868a78366ad5ee0cb3cc2a4cbe689b Mon Sep 17 00:00:00 2001 From: Arjan van dev Ven Date: Wed, 6 Feb 2008 05:16:00 +0100 Subject: [PATCH] fix historic ioremap() abuse in AGP Several AGP drivers right now use ioremap_nocache() on kernel ram in order to turn a page of regular memory uncached. There are two problems with this: 1) This is a total nightmare for the ioremap() implementation to keep various mappings of the same page coherent. 2) It's a total nightmare for the AGP code since it adds a ton of complexity in terms of keeping track of 2 different pointers to the same thing, in terms of error handling etc etc. This patch fixes this by making the AGP drivers use the new set_memory_XX APIs instead. Note: amd-k7-agp.c is built on Alpha too, and generic.c is built on ia64 as well, which do not yet have the set_memory_*() APIs, so for them some we have a few ugly #ifdefs - hopefully they'll be fixed soon. Signed-off-by: Arjan van de Ven Signed-off-by: Ingo Molnar Signed-off-by: Dave Airlie --- arch/x86/mm/ioremap.c | 2 ++ drivers/char/agp/amd-k7-agp.c | 9 +++++++++ drivers/char/agp/ati-agp.c | 16 +++------------- drivers/char/agp/generic.c | 9 +++++++++ drivers/char/agp/sworks-agp.c | 18 +++++------------- 5 files changed, 28 insertions(+), 26 deletions(-) diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c index 9f42d7e9c1..69f4981db8 100644 --- a/arch/x86/mm/ioremap.c +++ b/arch/x86/mm/ioremap.c @@ -126,6 +126,8 @@ static void __iomem *__ioremap(unsigned long phys_addr, unsigned long size, return NULL; } + WARN_ON_ONCE(page_is_ram(pfn)); + switch (mode) { case IOR_MODE_UNCACHED: default: diff --git a/drivers/char/agp/amd-k7-agp.c b/drivers/char/agp/amd-k7-agp.c index 87be46406d..fca4d7f304 100644 --- a/drivers/char/agp/amd-k7-agp.c +++ b/drivers/char/agp/amd-k7-agp.c @@ -41,6 +41,7 @@ static int amd_create_page_map(struct amd_page_map *page_map) if (page_map->real == NULL) return -ENOMEM; +#ifndef CONFIG_X86 SetPageReserved(virt_to_page(page_map->real)); global_cache_flush(); page_map->remapped = ioremap_nocache(virt_to_gart(page_map->real), @@ -52,6 +53,10 @@ static int amd_create_page_map(struct amd_page_map *page_map) return -ENOMEM; } global_cache_flush(); +#else + set_memory_uc(page_map->real, 1); + page_map->remapped = page_map->real; +#endif for (i = 0; i < PAGE_SIZE / sizeof(unsigned long); i++) { writel(agp_bridge->scratch_page, page_map->remapped+i); @@ -63,8 +68,12 @@ static int amd_create_page_map(struct amd_page_map *page_map) static void amd_free_page_map(struct amd_page_map *page_map) { +#ifndef CONFIG_X86 iounmap(page_map->remapped); ClearPageReserved(virt_to_page(page_map->real)); +#else + set_memory_wb(page_map->real, 1); +#endif free_page((unsigned long) page_map->real); } diff --git a/drivers/char/agp/ati-agp.c b/drivers/char/agp/ati-agp.c index 2d46b713c8..9ac3bef3bb 100644 --- a/drivers/char/agp/ati-agp.c +++ b/drivers/char/agp/ati-agp.c @@ -60,18 +60,9 @@ static int ati_create_page_map(struct ati_page_map *page_map) if (page_map->real == NULL) return -ENOMEM; - SetPageReserved(virt_to_page(page_map->real)); + set_memory_uc(page_map->real, 1); err = map_page_into_agp(virt_to_page(page_map->real)); - page_map->remapped = ioremap_nocache(virt_to_gart(page_map->real), - PAGE_SIZE); - if (page_map->remapped == NULL || err) { - ClearPageReserved(virt_to_page(page_map->real)); - free_page((unsigned long) page_map->real); - page_map->real = NULL; - return -ENOMEM; - } - /*CACHE_FLUSH();*/ - global_cache_flush(); + page_map->remapped = page_map->real; for (i = 0; i < PAGE_SIZE / sizeof(unsigned long); i++) { writel(agp_bridge->scratch_page, page_map->remapped+i); @@ -85,8 +76,7 @@ static int ati_create_page_map(struct ati_page_map *page_map) static void ati_free_page_map(struct ati_page_map *page_map) { unmap_page_from_agp(virt_to_page(page_map->real)); - iounmap(page_map->remapped); - ClearPageReserved(virt_to_page(page_map->real)); + set_memory_wb(page_map->real, 1); free_page((unsigned long) page_map->real); } diff --git a/drivers/char/agp/generic.c b/drivers/char/agp/generic.c index 7484bc759c..7fc0c99a3a 100644 --- a/drivers/char/agp/generic.c +++ b/drivers/char/agp/generic.c @@ -932,9 +932,14 @@ int agp_generic_create_gatt_table(struct agp_bridge_data *bridge) agp_gatt_table = (void *)table; bridge->driver->cache_flush(); +#ifdef CONFIG_X86 + set_memory_uc((unsigned long)table, 1 << page_order); + bridge->gatt_table = (void *)table; +#else bridge->gatt_table = ioremap_nocache(virt_to_gart(table), (PAGE_SIZE * (1 << page_order))); bridge->driver->cache_flush(); +#endif if (bridge->gatt_table == NULL) { for (page = virt_to_page(table); page <= virt_to_page(table_end); page++) @@ -991,7 +996,11 @@ int agp_generic_free_gatt_table(struct agp_bridge_data *bridge) * called, then all agp memory is deallocated and removed * from the table. */ +#ifdef CONFIG_X86 + set_memory_wb((unsigned long)bridge->gatt_table, 1 << page_order); +#else iounmap(bridge->gatt_table); +#endif table = (char *) bridge->gatt_table_real; table_end = table + ((PAGE_SIZE * (1 << page_order)) - 1); diff --git a/drivers/char/agp/sworks-agp.c b/drivers/char/agp/sworks-agp.c index 551ef25063..ae06f89820 100644 --- a/drivers/char/agp/sworks-agp.c +++ b/drivers/char/agp/sworks-agp.c @@ -52,28 +52,20 @@ static int serverworks_create_page_map(struct serverworks_page_map *page_map) if (page_map->real == NULL) { return -ENOMEM; } - SetPageReserved(virt_to_page(page_map->real)); - global_cache_flush(); - page_map->remapped = ioremap_nocache(virt_to_gart(page_map->real), - PAGE_SIZE); - if (page_map->remapped == NULL) { - ClearPageReserved(virt_to_page(page_map->real)); - free_page((unsigned long) page_map->real); - page_map->real = NULL; - return -ENOMEM; - } - global_cache_flush(); + + set_memory_uc(page_map->real, 1); + page_map->remapped = page_map->real; for (i = 0; i < PAGE_SIZE / sizeof(unsigned long); i++) writel(agp_bridge->scratch_page, page_map->remapped+i); + /* Red Pen: Everyone else does pci posting flush here */ return 0; } static void serverworks_free_page_map(struct serverworks_page_map *page_map) { - iounmap(page_map->remapped); - ClearPageReserved(virt_to_page(page_map->real)); + set_memory_wb(page_map->real, 1); free_page((unsigned long) page_map->real); } -- 2.39.5