diff options
Diffstat (limited to 'arch/ia64/kernel/uncached.c')
-rw-r--r-- | arch/ia64/kernel/uncached.c | 273 |
1 files changed, 0 insertions, 273 deletions
diff --git a/arch/ia64/kernel/uncached.c b/arch/ia64/kernel/uncached.c deleted file mode 100644 index a0fec82c56..0000000000 --- a/arch/ia64/kernel/uncached.c +++ /dev/null @@ -1,273 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * Copyright (C) 2001-2008 Silicon Graphics, Inc. All rights reserved. - * - * A simple uncached page allocator using the generic allocator. This - * allocator first utilizes the spare (spill) pages found in the EFI - * memmap and will then start converting cached pages to uncached ones - * at a granule at a time. Node awareness is implemented by having a - * pool of pages per node. - */ - -#include <linux/types.h> -#include <linux/kernel.h> -#include <linux/module.h> -#include <linux/init.h> -#include <linux/errno.h> -#include <linux/string.h> -#include <linux/efi.h> -#include <linux/nmi.h> -#include <linux/genalloc.h> -#include <linux/gfp.h> -#include <linux/pgtable.h> -#include <asm/efi.h> -#include <asm/page.h> -#include <asm/pal.h> -#include <linux/atomic.h> -#include <asm/tlbflush.h> - -struct uncached_pool { - struct gen_pool *pool; - struct mutex add_chunk_mutex; /* serialize adding a converted chunk */ - int nchunks_added; /* #of converted chunks added to pool */ - atomic_t status; /* smp called function's return status*/ -}; - -#define MAX_CONVERTED_CHUNKS_PER_NODE 2 - -struct uncached_pool uncached_pools[MAX_NUMNODES]; - - -static void uncached_ipi_visibility(void *data) -{ - int status; - struct uncached_pool *uc_pool = (struct uncached_pool *)data; - - status = ia64_pal_prefetch_visibility(PAL_VISIBILITY_PHYSICAL); - if ((status != PAL_VISIBILITY_OK) && - (status != PAL_VISIBILITY_OK_REMOTE_NEEDED)) - atomic_inc(&uc_pool->status); -} - - -static void uncached_ipi_mc_drain(void *data) -{ - int status; - struct uncached_pool *uc_pool = (struct uncached_pool *)data; - - status = ia64_pal_mc_drain(); - if (status != PAL_STATUS_SUCCESS) - atomic_inc(&uc_pool->status); -} - - -/* - * Add a new chunk of uncached memory pages to the specified pool. - * - * @pool: pool to add new chunk of uncached memory to - * @nid: node id of node to allocate memory from, or -1 - * - * This is accomplished by first allocating a granule of cached memory pages - * and then converting them to uncached memory pages. - */ -static int uncached_add_chunk(struct uncached_pool *uc_pool, int nid) -{ - struct page *page; - int status, i, nchunks_added = uc_pool->nchunks_added; - unsigned long c_addr, uc_addr; - - if (mutex_lock_interruptible(&uc_pool->add_chunk_mutex) != 0) - return -1; /* interrupted by a signal */ - - if (uc_pool->nchunks_added > nchunks_added) { - /* someone added a new chunk while we were waiting */ - mutex_unlock(&uc_pool->add_chunk_mutex); - return 0; - } - - if (uc_pool->nchunks_added >= MAX_CONVERTED_CHUNKS_PER_NODE) { - mutex_unlock(&uc_pool->add_chunk_mutex); - return -1; - } - - /* attempt to allocate a granule's worth of cached memory pages */ - - page = __alloc_pages_node(nid, - GFP_KERNEL | __GFP_ZERO | __GFP_THISNODE, - IA64_GRANULE_SHIFT-PAGE_SHIFT); - if (!page) { - mutex_unlock(&uc_pool->add_chunk_mutex); - return -1; - } - - /* convert the memory pages from cached to uncached */ - - c_addr = (unsigned long)page_address(page); - uc_addr = c_addr - PAGE_OFFSET + __IA64_UNCACHED_OFFSET; - - /* - * There's a small race here where it's possible for someone to - * access the page through /dev/mem halfway through the conversion - * to uncached - not sure it's really worth bothering about - */ - for (i = 0; i < (IA64_GRANULE_SIZE / PAGE_SIZE); i++) - SetPageUncached(&page[i]); - - flush_tlb_kernel_range(uc_addr, uc_addr + IA64_GRANULE_SIZE); - - status = ia64_pal_prefetch_visibility(PAL_VISIBILITY_PHYSICAL); - if (status == PAL_VISIBILITY_OK_REMOTE_NEEDED) { - atomic_set(&uc_pool->status, 0); - smp_call_function(uncached_ipi_visibility, uc_pool, 1); - if (atomic_read(&uc_pool->status)) - goto failed; - } else if (status != PAL_VISIBILITY_OK) - goto failed; - - preempt_disable(); - - flush_icache_range(uc_addr, uc_addr + IA64_GRANULE_SIZE); - - /* flush the just introduced uncached translation from the TLB */ - local_flush_tlb_all(); - - preempt_enable(); - - status = ia64_pal_mc_drain(); - if (status != PAL_STATUS_SUCCESS) - goto failed; - atomic_set(&uc_pool->status, 0); - smp_call_function(uncached_ipi_mc_drain, uc_pool, 1); - if (atomic_read(&uc_pool->status)) - goto failed; - - /* - * The chunk of memory pages has been converted to uncached so now we - * can add it to the pool. - */ - status = gen_pool_add(uc_pool->pool, uc_addr, IA64_GRANULE_SIZE, nid); - if (status) - goto failed; - - uc_pool->nchunks_added++; - mutex_unlock(&uc_pool->add_chunk_mutex); - return 0; - - /* failed to convert or add the chunk so give it back to the kernel */ -failed: - for (i = 0; i < (IA64_GRANULE_SIZE / PAGE_SIZE); i++) - ClearPageUncached(&page[i]); - - free_pages(c_addr, IA64_GRANULE_SHIFT-PAGE_SHIFT); - mutex_unlock(&uc_pool->add_chunk_mutex); - return -1; -} - - -/* - * uncached_alloc_page - * - * @starting_nid: node id of node to start with, or -1 - * @n_pages: number of contiguous pages to allocate - * - * Allocate the specified number of contiguous uncached pages on the - * requested node. If not enough contiguous uncached pages are available - * on the requested node, roundrobin starting with the next higher node. - */ -unsigned long uncached_alloc_page(int starting_nid, int n_pages) -{ - unsigned long uc_addr; - struct uncached_pool *uc_pool; - int nid; - - if (unlikely(starting_nid >= MAX_NUMNODES)) - return 0; - - if (starting_nid < 0) - starting_nid = numa_node_id(); - nid = starting_nid; - - do { - if (!node_state(nid, N_HIGH_MEMORY)) - continue; - uc_pool = &uncached_pools[nid]; - if (uc_pool->pool == NULL) - continue; - do { - uc_addr = gen_pool_alloc(uc_pool->pool, - n_pages * PAGE_SIZE); - if (uc_addr != 0) - return uc_addr; - } while (uncached_add_chunk(uc_pool, nid) == 0); - - } while ((nid = (nid + 1) % MAX_NUMNODES) != starting_nid); - - return 0; -} -EXPORT_SYMBOL(uncached_alloc_page); - - -/* - * uncached_free_page - * - * @uc_addr: uncached address of first page to free - * @n_pages: number of contiguous pages to free - * - * Free the specified number of uncached pages. - */ -void uncached_free_page(unsigned long uc_addr, int n_pages) -{ - int nid = paddr_to_nid(uc_addr - __IA64_UNCACHED_OFFSET); - struct gen_pool *pool = uncached_pools[nid].pool; - - if (unlikely(pool == NULL)) - return; - - if ((uc_addr & (0XFUL << 60)) != __IA64_UNCACHED_OFFSET) - panic("uncached_free_page invalid address %lx\n", uc_addr); - - gen_pool_free(pool, uc_addr, n_pages * PAGE_SIZE); -} -EXPORT_SYMBOL(uncached_free_page); - - -/* - * uncached_build_memmap, - * - * @uc_start: uncached starting address of a chunk of uncached memory - * @uc_end: uncached ending address of a chunk of uncached memory - * @arg: ignored, (NULL argument passed in on call to efi_memmap_walk_uc()) - * - * Called at boot time to build a map of pages that can be used for - * memory special operations. - */ -static int __init uncached_build_memmap(u64 uc_start, u64 uc_end, void *arg) -{ - int nid = paddr_to_nid(uc_start - __IA64_UNCACHED_OFFSET); - struct gen_pool *pool = uncached_pools[nid].pool; - size_t size = uc_end - uc_start; - - touch_softlockup_watchdog(); - - if (pool != NULL) { - memset((char *)uc_start, 0, size); - (void) gen_pool_add(pool, uc_start, size, nid); - } - return 0; -} - - -static int __init uncached_init(void) -{ - int nid; - - for_each_online_node(nid) { - uncached_pools[nid].pool = gen_pool_create(PAGE_SHIFT, nid); - mutex_init(&uncached_pools[nid].add_chunk_mutex); - } - - efi_memmap_walk_uc(uncached_build_memmap, NULL); - return 0; -} - -__initcall(uncached_init); |