diff options
Diffstat (limited to 'mm/nommu.c')
-rw-r--r-- | mm/nommu.c | 149 |
1 files changed, 14 insertions, 135 deletions
diff --git a/mm/nommu.c b/mm/nommu.c index 1a4a06d09..4cfc2fc93 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -33,7 +33,6 @@ #include <linux/security.h> #include <linux/syscalls.h> #include <linux/audit.h> -#include <linux/sched/sysctl.h> #include <linux/printk.h> #include <asm/uaccess.h> @@ -48,33 +47,11 @@ struct page *mem_map; unsigned long max_mapnr; EXPORT_SYMBOL(max_mapnr); unsigned long highest_memmap_pfn; -struct percpu_counter vm_committed_as; -int sysctl_overcommit_memory = OVERCOMMIT_GUESS; /* heuristic overcommit */ -int sysctl_overcommit_ratio = 50; /* default is 50% */ -unsigned long sysctl_overcommit_kbytes __read_mostly; -int sysctl_max_map_count = DEFAULT_MAX_MAP_COUNT; int sysctl_nr_trim_pages = CONFIG_NOMMU_INITIAL_TRIM_EXCESS; -unsigned long sysctl_user_reserve_kbytes __read_mostly = 1UL << 17; /* 128MB */ -unsigned long sysctl_admin_reserve_kbytes __read_mostly = 1UL << 13; /* 8MB */ int heap_stack_gap = 0; atomic_long_t mmap_pages_allocated; -/* - * The global memory commitment made in the system can be a metric - * that can be used to drive ballooning decisions when Linux is hosted - * as a guest. On Hyper-V, the host implements a policy engine for dynamically - * balancing memory across competing virtual machines that are hosted. - * Several metrics drive this policy engine including the guest reported - * memory commitment. - */ -unsigned long vm_memory_committed(void) -{ - return percpu_counter_read_positive(&vm_committed_as); -} - -EXPORT_SYMBOL_GPL(vm_memory_committed); - EXPORT_SYMBOL(mem_map); /* list of mapped, potentially shareable regions */ @@ -162,7 +139,7 @@ long __get_user_pages(struct task_struct *tsk, struct mm_struct *mm, if (pages) { pages[i] = virt_to_page(start); if (pages[i]) - page_cache_get(pages[i]); + get_page(pages[i]); } if (vmas) vmas[i] = vma; @@ -182,8 +159,7 @@ finish_or_fault: * slab page or a secondary page from a compound page * - don't permit access to VMAs that don't support it, such as I/O mappings */ -long get_user_pages(struct task_struct *tsk, struct mm_struct *mm, - unsigned long start, unsigned long nr_pages, +long get_user_pages(unsigned long start, unsigned long nr_pages, int write, int force, struct page **pages, struct vm_area_struct **vmas) { @@ -194,18 +170,16 @@ long get_user_pages(struct task_struct *tsk, struct mm_struct *mm, if (force) flags |= FOLL_FORCE; - return __get_user_pages(tsk, mm, start, nr_pages, flags, pages, vmas, - NULL); + return __get_user_pages(current, current->mm, start, nr_pages, flags, + pages, vmas, NULL); } EXPORT_SYMBOL(get_user_pages); -long get_user_pages_locked(struct task_struct *tsk, struct mm_struct *mm, - unsigned long start, unsigned long nr_pages, - int write, int force, struct page **pages, - int *locked) +long get_user_pages_locked(unsigned long start, unsigned long nr_pages, + int write, int force, struct page **pages, + int *locked) { - return get_user_pages(tsk, mm, start, nr_pages, write, force, - pages, NULL); + return get_user_pages(start, nr_pages, write, force, pages, NULL); } EXPORT_SYMBOL(get_user_pages_locked); @@ -216,19 +190,18 @@ long __get_user_pages_unlocked(struct task_struct *tsk, struct mm_struct *mm, { long ret; down_read(&mm->mmap_sem); - ret = get_user_pages(tsk, mm, start, nr_pages, write, force, - pages, NULL); + ret = __get_user_pages(tsk, mm, start, nr_pages, gup_flags, pages, + NULL, NULL); up_read(&mm->mmap_sem); return ret; } EXPORT_SYMBOL(__get_user_pages_unlocked); -long get_user_pages_unlocked(struct task_struct *tsk, struct mm_struct *mm, - unsigned long start, unsigned long nr_pages, +long get_user_pages_unlocked(unsigned long start, unsigned long nr_pages, int write, int force, struct page **pages) { - return __get_user_pages_unlocked(tsk, mm, start, nr_pages, write, - force, pages, 0); + return __get_user_pages_unlocked(current, current->mm, start, nr_pages, + write, force, pages, 0); } EXPORT_SYMBOL(get_user_pages_unlocked); @@ -1084,7 +1057,7 @@ static unsigned long determine_vm_flags(struct file *file, { unsigned long vm_flags; - vm_flags = calc_vm_prot_bits(prot) | calc_vm_flag_bits(flags); + vm_flags = calc_vm_prot_bits(prot, 0) | calc_vm_flag_bits(flags); /* vm_flags |= mm->def_flags; */ if (!(capabilities & NOMMU_MAP_DIRECT)) { @@ -1829,100 +1802,6 @@ void unmap_mapping_range(struct address_space *mapping, } EXPORT_SYMBOL(unmap_mapping_range); -/* - * Check that a process has enough memory to allocate a new virtual - * mapping. 0 means there is enough memory for the allocation to - * succeed and -ENOMEM implies there is not. - * - * We currently support three overcommit policies, which are set via the - * vm.overcommit_memory sysctl. See Documentation/vm/overcommit-accounting - * - * Strict overcommit modes added 2002 Feb 26 by Alan Cox. - * Additional code 2002 Jul 20 by Robert Love. - * - * cap_sys_admin is 1 if the process has admin privileges, 0 otherwise. - * - * Note this is a helper function intended to be used by LSMs which - * wish to use this logic. - */ -int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin) -{ - long free, allowed, reserve; - - vm_acct_memory(pages); - - /* - * Sometimes we want to use more memory than we have - */ - if (sysctl_overcommit_memory == OVERCOMMIT_ALWAYS) - return 0; - - if (sysctl_overcommit_memory == OVERCOMMIT_GUESS) { - free = global_page_state(NR_FREE_PAGES); - free += global_page_state(NR_FILE_PAGES); - - /* - * shmem pages shouldn't be counted as free in this - * case, they can't be purged, only swapped out, and - * that won't affect the overall amount of available - * memory in the system. - */ - free -= global_page_state(NR_SHMEM); - - free += get_nr_swap_pages(); - - /* - * Any slabs which are created with the - * SLAB_RECLAIM_ACCOUNT flag claim to have contents - * which are reclaimable, under pressure. The dentry - * cache and most inode caches should fall into this - */ - free += global_page_state(NR_SLAB_RECLAIMABLE); - - /* - * Leave reserved pages. The pages are not for anonymous pages. - */ - if (free <= totalreserve_pages) - goto error; - else - free -= totalreserve_pages; - - /* - * Reserve some for root - */ - if (!cap_sys_admin) - free -= sysctl_admin_reserve_kbytes >> (PAGE_SHIFT - 10); - - if (free > pages) - return 0; - - goto error; - } - - allowed = vm_commit_limit(); - /* - * Reserve some 3% for root - */ - if (!cap_sys_admin) - allowed -= sysctl_admin_reserve_kbytes >> (PAGE_SHIFT - 10); - - /* - * Don't let a single process grow so big a user can't recover - */ - if (mm) { - reserve = sysctl_user_reserve_kbytes >> (PAGE_SHIFT - 10); - allowed -= min_t(long, mm->total_vm / 32, reserve); - } - - if (percpu_counter_read_positive(&vm_committed_as) < allowed) - return 0; - -error: - vm_unacct_memory(pages); - - return -ENOMEM; -} - int filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf) { BUG(); |