| /* |
| * Simple NUMA memory policy for the Linux kernel. |
| * |
| * Copyright 2003,2004 Andi Kleen, SuSE Labs. |
| * (C) Copyright 2005 Christoph Lameter, Silicon Graphics, Inc. |
| * Subject to the GNU Public License, version 2. |
| * |
| * NUMA policy allows the user to give hints in which node(s) memory should |
| * be allocated. |
| * |
| * Support four policies per VMA and per process: |
| * |
| * The VMA policy has priority over the process policy for a page fault. |
| * |
| * interleave Allocate memory interleaved over a set of nodes, |
| * with normal fallback if it fails. |
| * For VMA based allocations this interleaves based on the |
| * offset into the backing object or offset into the mapping |
| * for anonymous memory. For process policy an process counter |
| * is used. |
| * |
| * bind Only allocate memory on a specific set of nodes, |
| * no fallback. |
| * FIXME: memory is allocated starting with the first node |
| * to the last. It would be better if bind would truly restrict |
| * the allocation to memory nodes instead |
| * |
| * preferred Try a specific node first before normal fallback. |
| * As a special case node -1 here means do the allocation |
| * on the local CPU. This is normally identical to default, |
| * but useful to set in a VMA when you have a non default |
| * process policy. |
| * |
| * default Allocate on the local node first, or when on a VMA |
| * use the process policy. This is what Linux always did |
| * in a NUMA aware kernel and still does by, ahem, default. |
| * |
| * The process policy is applied for most non interrupt memory allocations |
| * in that process' context. Interrupts ignore the policies and always |
| * try to allocate on the local CPU. The VMA policy is only applied for memory |
| * allocations for a VMA in the VM. |
| * |
| * Currently there are a few corner cases in swapping where the policy |
| * is not applied, but the majority should be handled. When process policy |
| * is used it is not remembered over swap outs/swap ins. |
| * |
| * Only the highest zone in the zone hierarchy gets policied. Allocations |
| * requesting a lower zone just use default policy. This implies that |
| * on systems with highmem kernel lowmem allocation don't get policied. |
| * Same with GFP_DMA allocations. |
| * |
| * For shmfs/tmpfs/hugetlbfs shared memory the policy is shared between |
| * all users and remembered even when nobody has memory mapped. |
| */ |
| |
| /* Notebook: |
| fix mmap readahead to honour policy and enable policy for any page cache |
| object |
| statistics for bigpages |
| global policy for page cache? currently it uses process policy. Requires |
| first item above. |
| handle mremap for shared memory (currently ignored for the policy) |
| grows down? |
| make bind policy root only? It can trigger oom much faster and the |
| kernel is not always grateful with that. |
| */ |
| |
| #include <linux/mempolicy.h> |
| #include <linux/mm.h> |
| #include <linux/highmem.h> |
| #include <linux/hugetlb.h> |
| #include <linux/kernel.h> |
| #include <linux/sched.h> |
| #include <linux/nodemask.h> |
| #include <linux/cpuset.h> |
| #include <linux/slab.h> |
| #include <linux/string.h> |
| #include <linux/module.h> |
| #include <linux/nsproxy.h> |
| #include <linux/interrupt.h> |
| #include <linux/init.h> |
| #include <linux/compat.h> |
| #include <linux/swap.h> |
| #include <linux/seq_file.h> |
| #include <linux/proc_fs.h> |
| #include <linux/migrate.h> |
| #include <linux/ksm.h> |
| #include <linux/rmap.h> |
| #include <linux/security.h> |
| #include <linux/syscalls.h> |
| #include <linux/ctype.h> |
| #include <linux/mm_inline.h> |
| |
| #include <asm/tlbflush.h> |
| #include <asm/uaccess.h> |
| |
| #include "internal.h" |
| |
| /* Internal flags */ |
| #define MPOL_MF_DISCONTIG_OK (MPOL_MF_INTERNAL << 0) /* Skip checks for continuous vmas */ |
| #define MPOL_MF_INVERT (MPOL_MF_INTERNAL << 1) /* Invert check for nodemask */ |
| #define MPOL_MF_STATS (MPOL_MF_INTERNAL << 2) /* Gather statistics */ |
| |
| static struct kmem_cache *policy_cache; |
| static struct kmem_cache *sn_cache; |
| |
| /* Highest zone. An specific allocation for a zone below that is not |
| policied. */ |
| enum zone_type policy_zone = 0; |
| |
| /* |
| * run-time system-wide default policy => local allocation |
| */ |
| struct mempolicy default_policy = { |
| .refcnt = ATOMIC_INIT(1), /* never free it */ |
| .mode = MPOL_PREFERRED, |
| .flags = MPOL_F_LOCAL, |
| }; |
| |
| static const struct mempolicy_operations { |
| int (*create)(struct mempolicy *pol, const nodemask_t *nodes); |
| /* |
| * If read-side task has no lock to protect task->mempolicy, write-side |
| * task will rebind the task->mempolicy by two step. The first step is |
| * setting all the newly nodes, and the second step is cleaning all the |
| * disallowed nodes. In this way, we can avoid finding no node to alloc |
| * page. |
| * If we have a lock to protect task->mempolicy in read-side, we do |
| * rebind directly. |
| * |
| * step: |
| * MPOL_REBIND_ONCE - do rebind work at once |
| * MPOL_REBIND_STEP1 - set all the newly nodes |
| * MPOL_REBIND_STEP2 - clean all the disallowed nodes |
| */ |
| void (*rebind)(struct mempolicy *pol, const nodemask_t *nodes, |
| enum mpol_rebind_step step); |
| } mpol_ops[MPOL_MAX]; |
| |
| /* Check that the nodemask contains at least one populated zone */ |
| static int is_valid_nodemask(const nodemask_t *nodemask) |
| { |
| int nd, k; |
| |
| for_each_node_mask(nd, *nodemask) { |
| struct zone *z; |
| |
| for (k = 0; k <= policy_zone; k++) { |
| z = &NODE_DATA(nd)->node_zones[k]; |
| if (z->present_pages > 0) |
| return 1; |
| } |
| } |
| |
| return 0; |
| } |
| |
| static inline int mpol_store_user_nodemask(const struct mempolicy *pol) |
| { |
| return pol->flags & MPOL_MODE_FLAGS; |
| } |
| |
| static void mpol_relative_nodemask(nodemask_t *ret, const nodemask_t *orig, |
| const nodemask_t *rel) |
| { |
| nodemask_t tmp; |
| nodes_fold(tmp, *orig, nodes_weight(*rel)); |
| nodes_onto(*ret, tmp, *rel); |
| } |
| |
| static int mpol_new_interleave(struct mempolicy *pol, const nodemask_t *nodes) |
| { |
| if (nodes_empty(*nodes)) |
| return -EINVAL; |
| pol->v.nodes = *nodes; |
| return 0; |
| } |
| |
| static int mpol_new_preferred(struct mempolicy *pol, const nodemask_t *nodes) |
| { |
| if (!nodes) |
| pol->flags |= MPOL_F_LOCAL; /* local allocation */ |
| else if (nodes_empty(*nodes)) |
| return -EINVAL; /* no allowed nodes */ |
| else |
| pol->v.preferred_node = first_node(*nodes); |
| return 0; |
| } |
| |
| static int mpol_new_bind(struct mempolicy *pol, const nodemask_t *nodes) |
| { |
| if (!is_valid_nodemask(nodes)) |
| return -EINVAL; |
| pol->v.nodes = *nodes; |
| return 0; |
| } |
| |
| /* |
| * mpol_set_nodemask is called after mpol_new() to set up the nodemask, if |
| * any, for the new policy. mpol_new() has already validated the nodes |
| * parameter with respect to the policy mode and flags. But, we need to |
| * handle an empty nodemask with MPOL_PREFERRED here. |
| * |
| * Must be called holding task's alloc_lock to protect task's mems_allowed |
| * and mempolicy. May also be called holding the mmap_semaphore for write. |
| */ |
| static int mpol_set_nodemask(struct mempolicy *pol, |
| const nodemask_t *nodes, struct nodemask_scratch *nsc) |
| { |
| int ret; |
| |
| /* if mode is MPOL_DEFAULT, pol is NULL. This is right. */ |
| if (pol == NULL) |
| return 0; |
| /* Check N_HIGH_MEMORY */ |
| nodes_and(nsc->mask1, |
| cpuset_current_mems_allowed, node_states[N_HIGH_MEMORY]); |
| |
| VM_BUG_ON(!nodes); |
| if (pol->mode == MPOL_PREFERRED && nodes_empty(*nodes)) |
| nodes = NULL; /* explicit local allocation */ |
| else { |
| if (pol->flags & MPOL_F_RELATIVE_NODES) |
| mpol_relative_nodemask(&nsc->mask2, nodes,&nsc->mask1); |
| else |
| nodes_and(nsc->mask2, *nodes, nsc->mask1); |
| |
| if (mpol_store_user_nodemask(pol)) |
| pol->w.user_nodemask = *nodes; |
| else |
| pol->w.cpuset_mems_allowed = |
| cpuset_current_mems_allowed; |
| } |
| |
| if (nodes) |
| ret = mpol_ops[pol->mode].create(pol, &nsc->mask2); |
| else |
| ret = mpol_ops[pol->mode].create(pol, NULL); |
| return ret; |
| } |
| |
| /* |
| * This function just creates a new policy, does some check and simple |
| * initialization. You must invoke mpol_set_nodemask() to set nodes. |
| */ |
| static struct mempolicy *mpol_new(unsigned short mode, unsigned short flags, |
| nodemask_t *nodes) |
| { |
| struct mempolicy *policy; |
| |
| pr_debug("setting mode %d flags %d nodes[0] %lx\n", |
| mode, flags, nodes ? nodes_addr(*nodes)[0] : -1); |
| |
| if (mode == MPOL_DEFAULT) { |
| if (nodes && !nodes_empty(*nodes)) |
| return ERR_PTR(-EINVAL); |
| return NULL; /* simply delete any existing policy */ |
| } |
| VM_BUG_ON(!nodes); |
| |
| /* |
| * MPOL_PREFERRED cannot be used with MPOL_F_STATIC_NODES or |
| * MPOL_F_RELATIVE_NODES if the nodemask is empty (local allocation). |
| * All other modes require a valid pointer to a non-empty nodemask. |
| */ |
| if (mode == MPOL_PREFERRED) { |
| if (nodes_empty(*nodes)) { |
| if (((flags & MPOL_F_STATIC_NODES) || |
| (flags & MPOL_F_RELATIVE_NODES))) |
| return ERR_PTR(-EINVAL); |
| } |
| } else if (nodes_empty(*nodes)) |
| return ERR_PTR(-EINVAL); |
| policy = kmem_cache_alloc(policy_cache, GFP_KERNEL); |
| if (!policy) |
| return ERR_PTR(-ENOMEM); |
| atomic_set(&policy->refcnt, 1); |
| policy->mode = mode; |
| policy->flags = flags; |
| |
| return policy; |
| } |
| |
| /* Slow path of a mpol destructor. */ |
| void __mpol_put(struct mempolicy *p) |
| { |
| if (!atomic_dec_and_test(&p->refcnt)) |
| return; |
| kmem_cache_free(policy_cache, p); |
| } |
| |
| static void mpol_rebind_default(struct mempolicy *pol, const nodemask_t *nodes, |
| enum mpol_rebind_step step) |
| { |
| } |
| |
| /* |
| * step: |
| * MPOL_REBIND_ONCE - do rebind work at once |
| * MPOL_REBIND_STEP1 - set all the newly nodes |
| * MPOL_REBIND_STEP2 - clean all the disallowed nodes |
| */ |
| static void mpol_rebind_nodemask(struct mempolicy *pol, const nodemask_t *nodes, |
| enum mpol_rebind_step step) |
| { |
| nodemask_t tmp; |
| |
| if (pol->flags & MPOL_F_STATIC_NODES) |
| nodes_and(tmp, pol->w.user_nodemask, *nodes); |
| else if (pol->flags & MPOL_F_RELATIVE_NODES) |
| mpol_relative_nodemask(&tmp, &pol->w.user_nodemask, nodes); |
| else { |
| /* |
| * if step == 1, we use ->w.cpuset_mems_allowed to cache the |
| * result |
| */ |
| if (step == MPOL_REBIND_ONCE || step == MPOL_REBIND_STEP1) { |
| nodes_remap(tmp, pol->v.nodes, |
| pol->w.cpuset_mems_allowed, *nodes); |
| pol->w.cpuset_mems_allowed = step ? tmp : *nodes; |
| } else if (step == MPOL_REBIND_STEP2) { |
| tmp = pol->w.cpuset_mems_allowed; |
| pol->w.cpuset_mems_allowed = *nodes; |
| } else |
| BUG(); |
| } |
| |
| if (nodes_empty(tmp)) |
| tmp = *nodes; |
| |
| if (step == MPOL_REBIND_STEP1) |
| nodes_or(pol->v.nodes, pol->v.nodes, tmp); |
| else if (step == MPOL_REBIND_ONCE || step == MPOL_REBIND_STEP2) |
| pol->v.nodes = tmp; |
| else |
| BUG(); |
| |
| if (!node_isset(current->il_next, tmp)) { |
| current->il_next = next_node(current->il_next, tmp); |
| if (current->il_next >= MAX_NUMNODES) |
| current->il_next = first_node(tmp); |
| if (current->il_next >= MAX_NUMNODES) |
| current->il_next = numa_node_id(); |
| } |
| } |
| |
| static void mpol_rebind_preferred(struct mempolicy *pol, |
| const nodemask_t *nodes, |
| enum mpol_rebind_step step) |
| { |
| nodemask_t tmp; |
| |
| if (pol->flags & MPOL_F_STATIC_NODES) { |
| int node = first_node(pol->w.user_nodemask); |
| |
| if (node_isset(node, *nodes)) { |
| pol->v.preferred_node = node; |
| pol->flags &= ~MPOL_F_LOCAL; |
| } else |
| pol->flags |= MPOL_F_LOCAL; |
| } else if (pol->flags & MPOL_F_RELATIVE_NODES) { |
| mpol_relative_nodemask(&tmp, &pol->w.user_nodemask, nodes); |
| pol->v.preferred_node = first_node(tmp); |
| } else if (!(pol->flags & MPOL_F_LOCAL)) { |
| pol->v.preferred_node = node_remap(pol->v.preferred_node, |
| pol->w.cpuset_mems_allowed, |
| *nodes); |
| pol->w.cpuset_mems_allowed = *nodes; |
| } |
| } |
| |
| /* |
| * mpol_rebind_policy - Migrate a policy to a different set of nodes |
| * |
| * If read-side task has no lock to protect task->mempolicy, write-side |
| * task will rebind the task->mempolicy by two step. The first step is |
| * setting all the newly nodes, and the second step is cleaning all the |
| * disallowed nodes. In this way, we can avoid finding no node to alloc |
| * page. |
| * If we have a lock to protect task->mempolicy in read-side, we do |
| * rebind directly. |
| * |
| * step: |
| * MPOL_REBIND_ONCE - do rebind work at once |
| * MPOL_REBIND_STEP1 - set all the newly nodes |
| * MPOL_REBIND_STEP2 - clean all the disallowed nodes |
| */ |
| static void mpol_rebind_policy(struct mempolicy *pol, const nodemask_t *newmask, |
| enum mpol_rebind_step step) |
| { |
| if (!pol) |
| return; |
| if (!mpol_store_user_nodemask(pol) && step == 0 && |
| nodes_equal(pol->w.cpuset_mems_allowed, *newmask)) |
| return; |
| |
| if (step == MPOL_REBIND_STEP1 && (pol->flags & MPOL_F_REBINDING)) |
| return; |
| |
| if (step == MPOL_REBIND_STEP2 && !(pol->flags & MPOL_F_REBINDING)) |
| BUG(); |
| |
| if (step == MPOL_REBIND_STEP1) |
| pol->flags |= MPOL_F_REBINDING; |
| else if (step == MPOL_REBIND_STEP2) |
| pol->flags &= ~MPOL_F_REBINDING; |
| else if (step >= MPOL_REBIND_NSTEP) |
| BUG(); |
| |
| mpol_ops[pol->mode].rebind(pol, newmask, step); |
| } |
| |
| /* |
| * Wrapper for mpol_rebind_policy() that just requires task |
| * pointer, and updates task mempolicy. |
| * |
| * Called with task's alloc_lock held. |
| */ |
| |
| void mpol_rebind_task(struct task_struct *tsk, const nodemask_t *new, |
| enum mpol_rebind_step step) |
| { |
| mpol_rebind_policy(tsk->mempolicy, new, step); |
| } |
| |
| /* |
| * Rebind each vma in mm to new nodemask. |
| * |
| * Call holding a reference to mm. Takes mm->mmap_sem during call. |
| */ |
| |
| void mpol_rebind_mm(struct mm_struct *mm, nodemask_t *new) |
| { |
| struct vm_area_struct *vma; |
| |
| down_write(&mm->mmap_sem); |
| for (vma = mm->mmap; vma; vma = vma->vm_next) |
| mpol_rebind_policy(vma->vm_policy, new, MPOL_REBIND_ONCE); |
| up_write(&mm->mmap_sem); |
| } |
| |
| static const struct mempolicy_operations mpol_ops[MPOL_MAX] = { |
| [MPOL_DEFAULT] = { |
| .rebind = mpol_rebind_default, |
| }, |
| [MPOL_INTERLEAVE] = { |
| .create = mpol_new_interleave, |
| .rebind = mpol_rebind_nodemask, |
| }, |
| [MPOL_PREFERRED] = { |
| .create = mpol_new_preferred, |
| .rebind = mpol_rebind_preferred, |
| }, |
| [MPOL_BIND] = { |
| .create = mpol_new_bind, |
| .rebind = mpol_rebind_nodemask, |
| }, |
| }; |
| |
| static void gather_stats(struct page *, void *, int pte_dirty); |
| static void migrate_page_add(struct page *page, struct list_head *pagelist, |
| unsigned long flags); |
| |
| /* Scan through pages checking if pages follow certain conditions. */ |
| static int check_pte_range(struct vm_area_struct *vma, pmd_t *pmd, |
| unsigned long addr, unsigned long end, |
| const nodemask_t *nodes, unsigned long flags, |
| void *private) |
| { |
| pte_t *orig_pte; |
| pte_t *pte; |
| spinlock_t *ptl; |
| |
| orig_pte = pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); |
| do { |
| struct page *page; |
| int nid; |
| |
| if (!pte_present(*pte)) |
| continue; |
| page = vm_normal_page(vma, addr, *pte); |
| if (!page) |
| continue; |
| /* |
| * vm_normal_page() filters out zero pages, but there might |
| * still be PageReserved pages to skip, perhaps in a VDSO. |
| * And we cannot move PageKsm pages sensibly or safely yet. |
| */ |
| if (PageReserved(page) || PageKsm(page)) |
| continue; |
| nid = page_to_nid(page); |
| if (node_isset(nid, *nodes) == !!(flags & MPOL_MF_INVERT)) |
| continue; |
| |
| if (flags & MPOL_MF_STATS) |
| gather_stats(page, private, pte_dirty(*pte)); |
| else if (flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) |
| migrate_page_add(page, private, flags); |
| else |
| break; |
| } while (pte++, addr += PAGE_SIZE, addr != end); |
| pte_unmap_unlock(orig_pte, ptl); |
| return addr != end; |
| } |
| |
| static inline int check_pmd_range(struct vm_area_struct *vma, pud_t *pud, |
| unsigned long addr, unsigned long end, |
| const nodemask_t *nodes, unsigned long flags, |
| void *private) |
| { |
| pmd_t *pmd; |
| unsigned long next; |
| |
| pmd = pmd_offset(pud, addr); |
| do { |
| next = pmd_addr_end(addr, end); |
| if (pmd_none_or_clear_bad(pmd)) |
| continue; |
| if (check_pte_range(vma, pmd, addr, next, nodes, |
| flags, private)) |
| return -EIO; |
| } while (pmd++, addr = next, addr != end); |
| return 0; |
| } |
| |
| static inline int check_pud_range(struct vm_area_struct *vma, pgd_t *pgd, |
| unsigned long addr, unsigned long end, |
| const nodemask_t *nodes, unsigned long flags, |
| void *private) |
| { |
| pud_t *pud; |
| unsigned long next; |
| |
| pud = pud_offset(pgd, addr); |
| do { |
| next = pud_addr_end(addr, end); |
| if (pud_none_or_clear_bad(pud)) |
| continue; |
| if (check_pmd_range(vma, pud, addr, next, nodes, |
| flags, private)) |
| return -EIO; |
| } while (pud++, addr = next, addr != end); |
| return 0; |
| } |
| |
| static inline int check_pgd_range(struct vm_area_struct *vma, |
| unsigned long addr, unsigned long end, |
| const nodemask_t *nodes, unsigned long flags, |
| void *private) |
| { |
| pgd_t *pgd; |
| unsigned long next; |
| |
| pgd = pgd_offset(vma->vm_mm, addr); |
| do { |
| next = pgd_addr_end(addr, end); |
| if (pgd_none_or_clear_bad(pgd)) |
| continue; |
| if (check_pud_range(vma, pgd, addr, next, nodes, |
| flags, private)) |
| return -EIO; |
| } while (pgd++, addr = next, addr != end); |
| return 0; |
| } |
| |
| /* |
| * Check if all pages in a range are on a set of nodes. |
| * If pagelist != NULL then isolate pages from the LRU and |
| * put them on the pagelist. |
| */ |
| static struct vm_area_struct * |
| check_range(struct mm_struct *mm, unsigned long start, unsigned long end, |
| const nodemask_t *nodes, unsigned long flags, void *private) |
| { |
| int err; |
| struct vm_area_struct *first, *vma, *prev; |
| |
| |
| first = find_vma(mm, start); |
| if (!first) |
| return ERR_PTR(-EFAULT); |
| prev = NULL; |
| for (vma = first; vma && vma->vm_start < end; vma = vma->vm_next) { |
| if (!(flags & MPOL_MF_DISCONTIG_OK)) { |
| if (!vma->vm_next && vma->vm_end < end) |
| return ERR_PTR(-EFAULT); |
| if (prev && prev->vm_end < vma->vm_start) |
| return ERR_PTR(-EFAULT); |
| } |
| if (!is_vm_hugetlb_page(vma) && |
| ((flags & MPOL_MF_STRICT) || |
| ((flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) && |
| vma_migratable(vma)))) { |
| unsigned long endvma = vma->vm_end; |
| |
| if (endvma > end) |
| endvma = end; |
| if (vma->vm_start > start) |
| start = vma->vm_start; |
| err = check_pgd_range(vma, start, endvma, nodes, |
| flags, private); |
| if (err) { |
| first = ERR_PTR(err); |
| break; |
| } |
| } |
| prev = vma; |
| } |
| return first; |
| } |
| |
| /* Apply policy to a single VMA */ |
| static int policy_vma(struct vm_area_struct *vma, struct mempolicy *new) |
| { |
| int err = 0; |
| struct mempolicy *old = vma->vm_policy; |
| |
| pr_debug("vma %lx-%lx/%lx vm_ops %p vm_file %p set_policy %p\n", |
| vma->vm_start, vma->vm_end, vma->vm_pgoff, |
| vma->vm_ops, vma->vm_file, |
| vma->vm_ops ? vma->vm_ops->set_policy : NULL); |
| |
| if (vma->vm_ops && vma->vm_ops->set_policy) |
| err = vma->vm_ops->set_policy(vma, new); |
| if (!err) { |
| mpol_get(new); |
| vma->vm_policy = new; |
| mpol_put(old); |
| } |
| return err; |
| } |
| |
| /* Step 2: apply policy to a range and do splits. */ |
| static int mbind_range(struct mm_struct *mm, unsigned long start, |
| unsigned long end, struct mempolicy *new_pol) |
| { |
| struct vm_area_struct *next; |
| struct vm_area_struct *prev; |
| struct vm_area_struct *vma; |
| int err = 0; |
| pgoff_t pgoff; |
| unsigned long vmstart; |
| unsigned long vmend; |
| |
| vma = find_vma_prev(mm, start, &prev); |
| if (!vma || vma->vm_start > start) |
| return -EFAULT; |
| |
| for (; vma && vma->vm_start < end; prev = vma, vma = next) { |
| next = vma->vm_next; |
| vmstart = max(start, vma->vm_start); |
| vmend = min(end, vma->vm_end); |
| |
| pgoff = vma->vm_pgoff + ((start - vma->vm_start) >> PAGE_SHIFT); |
| prev = vma_merge(mm, prev, vmstart, vmend, vma->vm_flags, |
| vma->anon_vma, vma->vm_file, pgoff, new_pol); |
| if (prev) { |
| vma = prev; |
| next = vma->vm_next; |
| continue; |
| } |
| if (vma->vm_start != vmstart) { |
| err = split_vma(vma->vm_mm, vma, vmstart, 1); |
| if (err) |
| goto out; |
| } |
| if (vma->vm_end != vmend) { |
| err = split_vma(vma->vm_mm, vma, vmend, 0); |
| if (err) |
| goto out; |
| } |
| err = policy_vma(vma, new_pol); |
| if (err) |
| goto out; |
| } |
| |
| out: |
| return err; |
| } |
| |
| /* |
| * Update task->flags PF_MEMPOLICY bit: set iff non-default |
| * mempolicy. Allows more rapid checking of this (combined perhaps |
| * with other PF_* flag bits) on memory allocation hot code paths. |
| * |
| * If called from outside this file, the task 'p' should -only- be |
| * a newly forked child not yet visible on the task list, because |
| * manipulating the task flags of a visible task is not safe. |
| * |
| * The above limitation is why this routine has the funny name |
| * mpol_fix_fork_child_flag(). |
| * |
| * It is also safe to call this with a task pointer of current, |
| * which the static wrapper mpol_set_task_struct_flag() does, |
| * for use within this file. |
| */ |
| |
| void mpol_fix_fork_child_flag(struct task_struct *p) |
| { |
| if (p->mempolicy) |
| p->flags |= PF_MEMPOLICY; |
| else |
| p->flags &= ~PF_MEMPOLICY; |
| } |
| |
| static void mpol_set_task_struct_flag(void) |
| { |
| mpol_fix_fork_child_flag(current); |
| } |
| |
| /* Set the process memory policy */ |
| static long do_set_mempolicy(unsigned short mode, unsigned short flags, |
| nodemask_t *nodes) |
| { |
| struct mempolicy *new, *old; |
| struct mm_struct *mm = current->mm; |
| NODEMASK_SCRATCH(scratch); |
| int ret; |
| |
| if (!scratch) |
| return -ENOMEM; |
| |
| new = mpol_new(mode, flags, nodes); |
| if (IS_ERR(new)) { |
| ret = PTR_ERR(new); |
| goto out; |
| } |
| /* |
| * prevent changing our mempolicy while show_numa_maps() |
| * is using it. |
| * Note: do_set_mempolicy() can be called at init time |
| * with no 'mm'. |
| */ |
| if (mm) |
| down_write(&mm->mmap_sem); |
| task_lock(current); |
| ret = mpol_set_nodemask(new, nodes, scratch); |
| if (ret) { |
| task_unlock(current); |
| if (mm) |
| up_write(&mm->mmap_sem); |
| mpol_put(new); |
| goto out; |
| } |
| old = current->mempolicy; |
| current->mempolicy = new; |
| mpol_set_task_struct_flag(); |
| if (new && new->mode == MPOL_INTERLEAVE && |
| nodes_weight(new->v.nodes)) |
| current->il_next = first_node(new->v.nodes); |
| task_unlock(current); |
| if (mm) |
| up_write(&mm->mmap_sem); |
| |
| mpol_put(old); |
| ret = 0; |
| out: |
| NODEMASK_SCRATCH_FREE(scratch); |
| return ret; |
| } |
| |
| /* |
| * Return nodemask for policy for get_mempolicy() query |
| * |
| * Called with task's alloc_lock held |
| */ |
| static void get_policy_nodemask(struct mempolicy *p, nodemask_t *nodes) |
| { |
| nodes_clear(*nodes); |
| if (p == &default_policy) |
| return; |
| |
| switch (p->mode) { |
| case MPOL_BIND: |
| /* Fall through */ |
| case MPOL_INTERLEAVE: |
| *nodes = p->v.nodes; |
| break; |
| case MPOL_PREFERRED: |
| if (!(p->flags & MPOL_F_LOCAL)) |
| node_set(p->v.preferred_node, *nodes); |
| /* else return empty node mask for local allocation */ |
| break; |
| default: |
| BUG(); |
| } |
| } |
| |
| static int lookup_node(struct mm_struct *mm, unsigned long addr) |
| { |
| struct page *p; |
| int err; |
| |
| err = get_user_pages(current, mm, addr & PAGE_MASK, 1, 0, 0, &p, NULL); |
| if (err >= 0) { |
| err = page_to_nid(p); |
| put_page(p); |
| } |
| return err; |
| } |
| |
| /* Retrieve NUMA policy */ |
| static long do_get_mempolicy(int *policy, nodemask_t *nmask, |
| unsigned long addr, unsigned long flags) |
| { |
| int err; |
| struct mm_struct *mm = current->mm; |
| struct vm_area_struct *vma = NULL; |
| struct mempolicy *pol = current->mempolicy; |
| |
| if (flags & |
| ~(unsigned long)(MPOL_F_NODE|MPOL_F_ADDR|MPOL_F_MEMS_ALLOWED)) |
| return -EINVAL; |
| |
| if (flags & MPOL_F_MEMS_ALLOWED) { |
| if (flags & (MPOL_F_NODE|MPOL_F_ADDR)) |
| return -EINVAL; |
| *policy = 0; /* just so it's initialized */ |
| task_lock(current); |
| *nmask = cpuset_current_mems_allowed; |
| task_unlock(current); |
| return 0; |
| } |
| |
| if (flags & MPOL_F_ADDR) { |
| /* |
| * Do NOT fall back to task policy if the |
| * vma/shared policy at addr is NULL. We |
| * want to return MPOL_DEFAULT in this case. |
| */ |
| down_read(&mm->mmap_sem); |
| vma = find_vma_intersection(mm, addr, addr+1); |
| if (!vma) { |
| up_read(&mm->mmap_sem); |
| return -EFAULT; |
| } |
| if (vma->vm_ops && vma->vm_ops->get_policy) |
| pol = vma->vm_ops->get_policy(vma, addr); |
| else |
| pol = vma->vm_policy; |
| } else if (addr) |
| return -EINVAL; |
| |
| if (!pol) |
| pol = &default_policy; /* indicates default behavior */ |
| |
| if (flags & MPOL_F_NODE) { |
| if (flags & MPOL_F_ADDR) { |
| err = lookup_node(mm, addr); |
| if (err < 0) |
| goto out; |
| *policy = err; |
| } else if (pol == current->mempolicy && |
| pol->mode == MPOL_INTERLEAVE) { |
| *policy = current->il_next; |
| } else { |
| err = -EINVAL; |
| goto out; |
| } |
| } else { |
| *policy = pol == &default_policy ? MPOL_DEFAULT : |
| pol->mode; |
| /* |
| * Internal mempolicy flags must be masked off before exposing |
| * the policy to userspace. |
| */ |
| *policy |= (pol->flags & MPOL_MODE_FLAGS); |
| } |
| |
| if (vma) { |
| up_read(¤t->mm->mmap_sem); |
| vma = NULL; |
| } |
| |
| err = 0; |
| if (nmask) { |
| if (mpol_store_user_nodemask(pol)) { |
| *nmask = pol->w.user_nodemask; |
| } else { |
| task_lock(current); |
| get_policy_nodemask(pol, nmask); |
| task_unlock(current); |
| } |
| } |
| |
| out: |
| mpol_cond_put(pol); |
| if (vma) |
| up_read(¤t->mm->mmap_sem); |
| return err; |
| } |
| |
| #ifdef CONFIG_MIGRATION |
| /* |
| * page migration |
| */ |
| static void migrate_page_add(struct page *page, struct list_head *pagelist, |
| unsigned long flags) |
| { |
| /* |
| * Avoid migrating a page that is shared with others. |
| */ |
| if ((flags & MPOL_MF_MOVE_ALL) || page_mapcount(page) == 1) { |
| if (!isolate_lru_page(page)) { |
| list_add_tail(&page->lru, pagelist); |
| inc_zone_page_state(page, NR_ISOLATED_ANON + |
| page_is_file_cache(page)); |
| } |
| } |
| } |
| |
| static struct page *new_node_page(struct page *page, unsigned long node, int **x) |
| { |
| return alloc_pages_exact_node(node, GFP_HIGHUSER_MOVABLE, 0); |
| } |
| |
| /* |
| * Migrate pages from one node to a target node. |
| * Returns error or the number of pages not migrated. |
| */ |
| static int migrate_to_node(struct mm_struct *mm, int source, int dest, |
| int flags) |
| { |
| nodemask_t nmask; |
| LIST_HEAD(pagelist); |
| int err = 0; |
| struct vm_area_struct *vma; |
| |
| nodes_clear(nmask); |
| node_set(source, nmask); |
| |
| vma = check_range(mm, mm->mmap->vm_start, mm->task_size, &nmask, |
| flags | MPOL_MF_DISCONTIG_OK, &pagelist); |
| if (IS_ERR(vma)) |
| return PTR_ERR(vma); |
| |
| if (!list_empty(&pagelist)) { |
| err = migrate_pages(&pagelist, new_node_page, dest, 0, true); |
| if (err) |
| putback_lru_pages(&pagelist); |
| } |
| |
| return err; |
| } |
| |
| /* |
| * Move pages between the two nodesets so as to preserve the physical |
| * layout as much as possible. |
| * |
| * Returns the number of page that could not be moved. |
| */ |
| int do_migrate_pages(struct mm_struct *mm, |
| const nodemask_t *from_nodes, const nodemask_t *to_nodes, int flags) |
| { |
| int busy = 0; |
| int err; |
| nodemask_t tmp; |
| |
| err = migrate_prep(); |
| if (err) |
| return err; |
| |
| down_read(&mm->mmap_sem); |
| |
| err = migrate_vmas(mm, from_nodes, to_nodes, flags); |
| if (err) |
| goto out; |
| |
| /* |
| * Find a 'source' bit set in 'tmp' whose corresponding 'dest' |
| * bit in 'to' is not also set in 'tmp'. Clear the found 'source' |
| * bit in 'tmp', and return that <source, dest> pair for migration. |
| * The pair of nodemasks 'to' and 'from' define the map. |
| * |
| * If no pair of bits is found that way, fallback to picking some |
| * pair of 'source' and 'dest' bits that are not the same. If the |
| * 'source' and 'dest' bits are the same, this represents a node |
| * that will be migrating to itself, so no pages need move. |
| * |
| * If no bits are left in 'tmp', or if all remaining bits left |
| * in 'tmp' correspond to the same bit in 'to', return false |
| * (nothing left to migrate). |
| * |
| * This lets us pick a pair of nodes to migrate between, such that |
| * if possible the dest node is not already occupied by some other |
| * source node, minimizing the risk of overloading the memory on a |
| * node that would happen if we migrated incoming memory to a node |
| * before migrating outgoing memory source that same node. |
| * |
| * A single scan of tmp is sufficient. As we go, we remember the |
| * most recent <s, d> pair that moved (s != d). If we find a pair |
| * that not only moved, but what's better, moved to an empty slot |
| * (d is not set in tmp), then we break out then, with that pair. |
| * Otherwise when we finish scannng from_tmp, we at least have the |
| * most recent <s, d> pair that moved. If we get all the way through |
| * the scan of tmp without finding any node that moved, much less |
| * moved to an empty node, then there is nothing left worth migrating. |
| */ |
| |
| tmp = *from_nodes; |
| while (!nodes_empty(tmp)) { |
| int s,d; |
| int source = -1; |
| int dest = 0; |
| |
| for_each_node_mask(s, tmp) { |
| d = node_remap(s, *from_nodes, *to_nodes); |
| if (s == d) |
| continue; |
| |
| source = s; /* Node moved. Memorize */ |
| dest = d; |
| |
| /* dest not in remaining from nodes? */ |
| if (!node_isset(dest, tmp)) |
| break; |
| } |
| if (source == -1) |
| break; |
| |
| node_clear(source, tmp); |
| err = migrate_to_node(mm, source, dest, flags); |
| if (err > 0) |
| busy += err; |
| if (err < 0) |
| break; |
| } |
| out: |
| up_read(&mm->mmap_sem); |
| if (err < 0) |
| return err; |
| return busy; |
| |
| } |
| |
| /* |
| * Allocate a new page for page migration based on vma policy. |
| * Start assuming that page is mapped by vma pointed to by @private. |
| * Search forward from there, if not. N.B., this assumes that the |
| * list of pages handed to migrate_pages()--which is how we get here-- |
| * is in virtual address order. |
| */ |
| static struct page *new_vma_page(struct page *page, unsigned long private, int **x) |
| { |
| struct vm_area_struct *vma = (struct vm_area_struct *)private; |
| unsigned long uninitialized_var(address); |
| |
| while (vma) { |
| address = page_address_in_vma(page, vma); |
| if (address != -EFAULT) |
| break; |
| vma = vma->vm_next; |
| } |
| |
| /* |
| * if !vma, alloc_page_vma() will use task or system default policy |
| */ |
| return alloc_page_vma(GFP_HIGHUSER_MOVABLE, vma, address); |
| } |
| #else |
| |
| static void migrate_page_add(struct page *page, struct list_head *pagelist, |
| unsigned long flags) |
| { |
| } |
| |
| int do_migrate_pages(struct mm_struct *mm, |
| const nodemask_t *from_nodes, const nodemask_t *to_nodes, int flags) |
| { |
| return -ENOSYS; |
| } |
| |
| static struct page *new_vma_page(struct page *page, unsigned long private, int **x) |
| { |
| return NULL; |
| } |
| #endif |
| |
| static long do_mbind(unsigned long start, unsigned long len, |
| unsigned short mode, unsigned short mode_flags, |
| nodemask_t *nmask, unsigned long flags) |
| { |
| struct vm_area_struct *vma; |
| struct mm_struct *mm = current->mm; |
| struct mempolicy *new; |
| unsigned long end; |
| int err; |
| LIST_HEAD(pagelist); |
| |
| if (flags & ~(unsigned long)(MPOL_MF_STRICT | |
| MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) |
| return -EINVAL; |
| if ((flags & MPOL_MF_MOVE_ALL) && !capable(CAP_SYS_NICE)) |
| return -EPERM; |
| |
| if (start & ~PAGE_MASK) |
| return -EINVAL; |
| |
| if (mode == MPOL_DEFAULT) |
| flags &= ~MPOL_MF_STRICT; |
| |
| len = (len + PAGE_SIZE - 1) & PAGE_MASK; |
| end = start + len; |
| |
| if (end < start) |
| return -EINVAL; |
| if (end == start) |
| return 0; |
| |
| new = mpol_new(mode, mode_flags, nmask); |
| if (IS_ERR(new)) |
| return PTR_ERR(new); |
| |
| /* |
| * If we are using the default policy then operation |
| * on discontinuous address spaces is okay after all |
| */ |
| if (!new) |
| flags |= MPOL_MF_DISCONTIG_OK; |
| |
| pr_debug("mbind %lx-%lx mode:%d flags:%d nodes:%lx\n", |
| start, start + len, mode, mode_flags, |
| nmask ? nodes_addr(*nmask)[0] : -1); |
| |
| if (flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) { |
| |
| err = migrate_prep(); |
| if (err) |
| goto mpol_out; |
| } |
| { |
| NODEMASK_SCRATCH(scratch); |
| if (scratch) { |
| down_write(&mm->mmap_sem); |
| task_lock(current); |
| err = mpol_set_nodemask(new, nmask, scratch); |
| task_unlock(current); |
| if (err) |
| up_write(&mm->mmap_sem); |
| } else |
| err = -ENOMEM; |
| NODEMASK_SCRATCH_FREE(scratch); |
| } |
| if (err) |
| goto mpol_out; |
| |
| vma = check_range(mm, start, end, nmask, |
| flags | MPOL_MF_INVERT, &pagelist); |
| |
| err = PTR_ERR(vma); |
| if (!IS_ERR(vma)) { |
| int nr_failed = 0; |
| |
| err = mbind_range(mm, start, end, new); |
| |
| if (!list_empty(&pagelist)) { |
| nr_failed = migrate_pages(&pagelist, new_vma_page, |
| (unsigned long)vma, 0, true); |
| if (nr_failed) |
| putback_lru_pages(&pagelist); |
| } |
| |
| if (!err && nr_failed && (flags & MPOL_MF_STRICT)) |
| err = -EIO; |
| } else |
| putback_lru_pages(&pagelist); |
| |
| up_write(&mm->mmap_sem); |
| mpol_out: |
| mpol_put(new); |
| return err; |
| } |
| |
| /* |
| * User space interface with variable sized bitmaps for nodelists. |
| */ |
| |
| /* Copy a node mask from user space. */ |
| static int get_nodes(nodemask_t *nodes, const unsigned long __user *nmask, |
| unsigned long maxnode) |
| { |
| unsigned long k; |
| unsigned long nlongs; |
| unsigned long endmask; |
| |
| --maxnode; |
| nodes_clear(*nodes); |
| if (maxnode == 0 || !nmask) |
| return 0; |
| if (maxnode > PAGE_SIZE*BITS_PER_BYTE) |
| return -EINVAL; |
| |
| nlongs = BITS_TO_LONGS(maxnode); |
| if ((maxnode % BITS_PER_LONG) == 0) |
| endmask = ~0UL; |
| else |
| endmask = (1UL << (maxnode % BITS_PER_LONG)) - 1; |
| |
| /* When the user specified more nodes than supported just check |
| if the non supported part is all zero. */ |
| if (nlongs > BITS_TO_LONGS(MAX_NUMNODES)) { |
| if (nlongs > PAGE_SIZE/sizeof(long)) |
| return -EINVAL; |
| for (k = BITS_TO_LONGS(MAX_NUMNODES); k < nlongs; k++) { |
| unsigned long t; |
| if (get_user(t, nmask + k)) |
| return -EFAULT; |
| if (k == nlongs - 1) { |
| if (t & endmask) |
| return -EINVAL; |
| } else if (t) |
| return -EINVAL; |
| } |
| nlongs = BITS_TO_LONGS(MAX_NUMNODES); |
| endmask = ~0UL; |
| } |
| |
| if (copy_from_user(nodes_addr(*nodes), nmask, nlongs*sizeof(unsigned long))) |
| return -EFAULT; |
| nodes_addr(*nodes)[nlongs-1] &= endmask; |
| return 0; |
| } |
| |
| /* Copy a kernel node mask to user space */ |
| static int copy_nodes_to_user(unsigned long __user *mask, unsigned long maxnode, |
| nodemask_t *nodes) |
| { |
| unsigned long copy = ALIGN(maxnode-1, 64) / 8; |
| const int nbytes = BITS_TO_LONGS(MAX_NUMNODES) * sizeof(long); |
| |
| if (copy > nbytes) { |
| if (copy > PAGE_SIZE) |
| return -EINVAL; |
| if (clear_user((char __user *)mask + nbytes, copy - nbytes)) |
| return -EFAULT; |
| copy = nbytes; |
| } |
| return copy_to_user(mask, nodes_addr(*nodes), copy) ? -EFAULT : 0; |
| } |
| |
| SYSCALL_DEFINE6(mbind, unsigned long, start, unsigned long, len, |
| unsigned long, mode, unsigned long __user *, nmask, |
| unsigned long, maxnode, unsigned, flags) |
| { |
| nodemask_t nodes; |
| int err; |
| unsigned short mode_flags; |
| |
| mode_flags = mode & MPOL_MODE_FLAGS; |
| mode &= ~MPOL_MODE_FLAGS; |
| if (mode >= MPOL_MAX) |
| return -EINVAL; |
| if ((mode_flags & MPOL_F_STATIC_NODES) && |
| (mode_flags & MPOL_F_RELATIVE_NODES)) |
| return -EINVAL; |
| err = get_nodes(&nodes, nmask, maxnode); |
| if (err) |
| return err; |
| return do_mbind(start, len, mode, mode_flags, &nodes, flags); |
| } |
| |
| /* Set the process memory policy */ |
| SYSCALL_DEFINE3(set_mempolicy, int, mode, unsigned long __user *, nmask, |
| unsigned long, maxnode) |
| { |
| int err; |
| nodemask_t nodes; |
| unsigned short flags; |
| |
| flags = mode & MPOL_MODE_FLAGS; |
| mode &= ~MPOL_MODE_FLAGS; |
| if ((unsigned int)mode >= MPOL_MAX) |
| return -EINVAL; |
| if ((flags & MPOL_F_STATIC_NODES) && (flags & MPOL_F_RELATIVE_NODES)) |
| return -EINVAL; |
| err = get_nodes(&nodes, nmask, maxnode); |
| if (err) |
| return err; |
| return do_set_mempolicy(mode, flags, &nodes); |
| } |
| |
| SYSCALL_DEFINE4(migrate_pages, pid_t, pid, unsigned long, maxnode, |
| const unsigned long __user *, old_nodes, |
| const unsigned long __user *, new_nodes) |
| { |
| const struct cred *cred = current_cred(), *tcred; |
| struct mm_struct *mm = NULL; |
| struct task_struct *task; |
| nodemask_t task_nodes; |
| int err; |
| nodemask_t *old; |
| nodemask_t *new; |
| NODEMASK_SCRATCH(scratch); |
| |
| if (!scratch) |
| return -ENOMEM; |
| |
| old = &scratch->mask1; |
| new = &scratch->mask2; |
| |
| err = get_nodes(old, old_nodes, maxnode); |
| if (err) |
| goto out; |
| |
| err = get_nodes(new, new_nodes, maxnode); |
| if (err) |
| goto out; |
| |
| /* Find the mm_struct */ |
| rcu_read_lock(); |
| read_lock(&tasklist_lock); |
| task = pid ? find_task_by_vpid(pid) : current; |
| if (!task) { |
| read_unlock(&tasklist_lock); |
| rcu_read_unlock(); |
| err = -ESRCH; |
| goto out; |
| } |
| mm = get_task_mm(task); |
| read_unlock(&tasklist_lock); |
| rcu_read_unlock(); |
| |
| err = -EINVAL; |
| if (!mm) |
| goto out; |
| |
| /* |
| * Check if this process has the right to modify the specified |
| * process. The right exists if the process has administrative |
| * capabilities, superuser privileges or the same |
| * userid as the target process. |
| */ |
| rcu_read_lock(); |
| tcred = __task_cred(task); |
| if (cred->euid != tcred->suid && cred->euid != tcred->uid && |
| cred->uid != tcred->suid && cred->uid != tcred->uid && |
| !capable(CAP_SYS_NICE)) { |
| rcu_read_unlock(); |
| err = -EPERM; |
| goto out; |
| } |
| rcu_read_unlock(); |
| |
| task_nodes = cpuset_mems_allowed(task); |
| /* Is the user allowed to access the target nodes? */ |
| if (!nodes_subset(*new, task_nodes) && !capable(CAP_SYS_NICE)) { |
| err = -EPERM; |
| goto out; |
| } |
| |
| if (!nodes_subset(*new, node_states[N_HIGH_MEMORY])) { |
| err = -EINVAL; |
| goto out; |
| } |
| |
| err = security_task_movememory(task); |
| if (err) |
| goto out; |
| |
| err = do_migrate_pages(mm, old, new, |
| capable(CAP_SYS_NICE) ? MPOL_MF_MOVE_ALL : MPOL_MF_MOVE); |
| out: |
| if (mm) |
| mmput(mm); |
| NODEMASK_SCRATCH_FREE(scratch); |
| |
| return err; |
| } |
| |
| |
| /* Retrieve NUMA policy */ |
| SYSCALL_DEFINE5(get_mempolicy, int __user *, policy, |
| unsigned long __user *, nmask, unsigned long, maxnode, |
| unsigned long, addr, unsigned long, flags) |
| { |
| int err; |
| int uninitialized_var(pval); |
| nodemask_t nodes; |
| |
| if (nmask != NULL && maxnode < MAX_NUMNODES) |
| return -EINVAL; |
| |
| err = do_get_mempolicy(&pval, &nodes, addr, flags); |
| |
| if (err) |
| return err; |
| |
| if (policy && put_user(pval, policy)) |
| return -EFAULT; |
| |
| if (nmask) |
| err = copy_nodes_to_user(nmask, maxnode, &nodes); |
| |
| return err; |
| } |
| |
| #ifdef CONFIG_COMPAT |
| |
| asmlinkage long compat_sys_get_mempolicy(int __user *policy, |
| compat_ulong_t __user *nmask, |
| compat_ulong_t maxnode, |
| compat_ulong_t addr, compat_ulong_t flags) |
| { |
| long err; |
| unsigned long __user *nm = NULL; |
| unsigned long nr_bits, alloc_size; |
| DECLARE_BITMAP(bm, MAX_NUMNODES); |
| |
| nr_bits = min_t(unsigned long, maxnode-1, MAX_NUMNODES); |
| alloc_size = ALIGN(nr_bits, BITS_PER_LONG) / 8; |
| |
| if (nmask) |
| nm = compat_alloc_user_space(alloc_size); |
| |
| err = sys_get_mempolicy(policy, nm, nr_bits+1, addr, flags); |
| |
| if (!err && nmask) { |
| err = copy_from_user(bm, nm, alloc_size); |
| /* ensure entire bitmap is zeroed */ |
| err |= clear_user(nmask, ALIGN(maxnode-1, 8) / 8); |
| err |= compat_put_bitmap(nmask, bm, nr_bits); |
| } |
| |
| return err; |
| } |
| |
| asmlinkage long compat_sys_set_mempolicy(int mode, compat_ulong_t __user *nmask, |
| compat_ulong_t maxnode) |
| { |
| long err = 0; |
| unsigned long __user *nm = NULL; |
| unsigned long nr_bits, alloc_size; |
| DECLARE_BITMAP(bm, MAX_NUMNODES); |
| |
| nr_bits = min_t(unsigned long, maxnode-1, MAX_NUMNODES); |
| alloc_size = ALIGN(nr_bits, BITS_PER_LONG) / 8; |
| |
| if (nmask) { |
| err = compat_get_bitmap(bm, nmask, nr_bits); |
| nm = compat_alloc_user_space(alloc_size); |
| err |= copy_to_user(nm, bm, alloc_size); |
| } |
| |
| if (err) |
| return -EFAULT; |
| |
| return sys_set_mempolicy(mode, nm, nr_bits+1); |
| } |
| |
| asmlinkage long compat_sys_mbind(compat_ulong_t start, compat_ulong_t len, |
| compat_ulong_t mode, compat_ulong_t __user *nmask, |
| compat_ulong_t maxnode, compat_ulong_t flags) |
| { |
| long err = 0; |
| unsigned long __user *nm = NULL; |
| unsigned long nr_bits, alloc_size; |
| nodemask_t bm; |
| |
| nr_bits = min_t(unsigned long, maxnode-1, MAX_NUMNODES); |
| alloc_size = ALIGN(nr_bits, BITS_PER_LONG) / 8; |
| |
| if (nmask) { |
| err = compat_get_bitmap(nodes_addr(bm), nmask, nr_bits); |
| nm = compat_alloc_user_space(alloc_size); |
| err |= copy_to_user(nm, nodes_addr(bm), alloc_size); |
| } |
| |
| if (err) |
| return -EFAULT; |
| |
| return sys_mbind(start, len, mode, nm, nr_bits+1, flags); |
| } |
| |
| #endif |
| |
| /* |
| * get_vma_policy(@task, @vma, @addr) |
| * @task - task for fallback if vma policy == default |
| * @vma - virtual memory area whose policy is sought |
| * @addr - address in @vma for shared policy lookup |
| * |
| * Returns effective policy for a VMA at specified address. |
| * Falls back to @task or system default policy, as necessary. |
| * Current or other task's task mempolicy and non-shared vma policies |
| * are protected by the task's mmap_sem, which must be held for read by |
| * the caller. |
| * Shared policies [those marked as MPOL_F_SHARED] require an extra reference |
| * count--added by the get_policy() vm_op, as appropriate--to protect against |
| * freeing by another task. It is the caller's responsibility to free the |
| * extra reference for shared policies. |
| */ |
| static struct mempolicy *get_vma_policy(struct task_struct *task, |
| struct vm_area_struct *vma, unsigned long addr) |
| { |
| struct mempolicy *pol = task->mempolicy; |
| |
| if (vma) { |
| if (vma->vm_ops && vma->vm_ops->get_policy) { |
| struct mempolicy *vpol = vma->vm_ops->get_policy(vma, |
| addr); |
| if (vpol) |
| pol = vpol; |
| } else if (vma->vm_policy) |
| pol = vma->vm_policy; |
| } |
| if (!pol) |
| pol = &default_policy; |
| return pol; |
| } |
| |
| /* |
| * Return a nodemask representing a mempolicy for filtering nodes for |
| * page allocation |
| */ |
| static nodemask_t *policy_nodemask(gfp_t gfp, struct mempolicy *policy) |
| { |
| /* Lower zones don't get a nodemask applied for MPOL_BIND */ |
| if (unlikely(policy->mode == MPOL_BIND) && |
| gfp_zone(gfp) >= policy_zone && |
| cpuset_nodemask_valid_mems_allowed(&policy->v.nodes)) |
| return &policy->v.nodes; |
| |
| return NULL; |
| } |
| |
| /* Return a zonelist indicated by gfp for node representing a mempolicy */ |
| static struct zonelist *policy_zonelist(gfp_t gfp, struct mempolicy *policy) |
| { |
| int nd = numa_node_id(); |
| |
| switch (policy->mode) { |
| case MPOL_PREFERRED: |
| if (!(policy->flags & MPOL_F_LOCAL)) |
| nd = policy->v.preferred_node; |
| break; |
| case MPOL_BIND: |
| /* |
| * Normally, MPOL_BIND allocations are node-local within the |
| * allowed nodemask. However, if __GFP_THISNODE is set and the |
| * current node isn't part of the mask, we use the zonelist for |
| * the first node in the mask instead. |
| */ |
| if (unlikely(gfp & __GFP_THISNODE) && |
| unlikely(!node_isset(nd, policy->v.nodes))) |
| nd = first_node(policy->v.nodes); |
| break; |
| default: |
| BUG(); |
| } |
| return node_zonelist(nd, gfp); |
| } |
| |
| /* Do dynamic interleaving for a process */ |
| static unsigned interleave_nodes(struct mempolicy *policy) |
| { |
| unsigned nid, next; |
| struct task_struct *me = current; |
| |
| nid = me->il_next; |
| next = next_node(nid, policy->v.nodes); |
| if (next >= MAX_NUMNODES) |
| next = first_node(policy->v.nodes); |
| if (next < MAX_NUMNODES) |
| me->il_next = next; |
| return nid; |
| } |
| |
| /* |
| * Depending on the memory policy provide a node from which to allocate the |
| * next slab entry. |
| * @policy must be protected by freeing by the caller. If @policy is |
| * the current task's mempolicy, this protection is implicit, as only the |
| * task can change it's policy. The system default policy requires no |
| * such protection. |
| */ |
| unsigned slab_node(struct mempolicy *policy) |
| { |
| if (!policy || policy->flags & MPOL_F_LOCAL) |
| return numa_node_id(); |
| |
| switch (policy->mode) { |
| case MPOL_PREFERRED: |
| /* |
| * handled MPOL_F_LOCAL above |
| */ |
| return policy->v.preferred_node; |
| |
| case MPOL_INTERLEAVE: |
| return interleave_nodes(policy); |
| |
| case MPOL_BIND: { |
| /* |
| * Follow bind policy behavior and start allocation at the |
| * first node. |
| */ |
| struct zonelist *zonelist; |
| struct zone *zone; |
| enum zone_type highest_zoneidx = gfp_zone(GFP_KERNEL); |
| zonelist = &NODE_DATA(numa_node_id())->node_zonelists[0]; |
| (void)first_zones_zonelist(zonelist, highest_zoneidx, |
| &policy->v.nodes, |
| &zone); |
| return zone ? zone->node : numa_node_id(); |
| } |
| |
| default: |
| BUG(); |
| } |
| } |
| |
| /* Do static interleaving for a VMA with known offset. */ |
| static unsigned offset_il_node(struct mempolicy *pol, |
| struct vm_area_struct *vma, unsigned long off) |
| { |
| unsigned nnodes = nodes_weight(pol->v.nodes); |
| unsigned target; |
| int c; |
| int nid = -1; |
| |
| if (!nnodes) |
| return numa_node_id(); |
| target = (unsigned int)off % nnodes; |
| c = 0; |
| do { |
| nid = next_node(nid, pol->v.nodes); |
| c++; |
| } while (c <= target); |
| return nid; |
| } |
| |
| /* Determine a node number for interleave */ |
| static inline unsigned interleave_nid(struct mempolicy *pol, |
| struct vm_area_struct *vma, unsigned long addr, int shift) |
| { |
| if (vma) { |
| unsigned long off; |
| |
| /* |
| * for small pages, there is no difference between |
| * shift and PAGE_SHIFT, so the bit-shift is safe. |
| * for huge pages, since vm_pgoff is in units of small |
| * pages, we need to shift off the always 0 bits to get |
| * a useful offset. |
| */ |
| BUG_ON(shift < PAGE_SHIFT); |
| off = vma->vm_pgoff >> (shift - PAGE_SHIFT); |
| off += (addr - vma->vm_start) >> shift; |
| return offset_il_node(pol, vma, off); |
| } else |
| return interleave_nodes(pol); |
| } |
| |
| #ifdef CONFIG_HUGETLBFS |
| /* |
| * huge_zonelist(@vma, @addr, @gfp_flags, @mpol) |
| * @vma = virtual memory area whose policy is sought |
| * @addr = address in @vma for shared policy lookup and interleave policy |
| * @gfp_flags = for requested zone |
| * @mpol = pointer to mempolicy pointer for reference counted mempolicy |
| * @nodemask = pointer to nodemask pointer for MPOL_BIND nodemask |
| * |
| * Returns a zonelist suitable for a huge page allocation and a pointer |
| * to the struct mempolicy for conditional unref after allocation. |
| * If the effective policy is 'BIND, returns a pointer to the mempolicy's |
| * @nodemask for filtering the zonelist. |
| * |
| * Must be protected by get_mems_allowed() |
| */ |
| struct zonelist *huge_zonelist(struct vm_area_struct *vma, unsigned long addr, |
| gfp_t gfp_flags, struct mempolicy **mpol, |
| nodemask_t **nodemask) |
| { |
| struct zonelist *zl; |
| |
| *mpol = get_vma_policy(current, vma, addr); |
| *nodemask = NULL; /* assume !MPOL_BIND */ |
| |
| if (unlikely((*mpol)->mode == MPOL_INTERLEAVE)) { |
| zl = node_zonelist(interleave_nid(*mpol, vma, addr, |
| huge_page_shift(hstate_vma(vma))), gfp_flags); |
| } else { |
| zl = policy_zonelist(gfp_flags, *mpol); |
| if ((*mpol)->mode == MPOL_BIND) |
| *nodemask = &(*mpol)->v.nodes; |
| } |
| return zl; |
| } |
| |
| /* |
| * init_nodemask_of_mempolicy |
| * |
| * If the current task's mempolicy is "default" [NULL], return 'false' |
| * to indicate default policy. Otherwise, extract the policy nodemask |
| * for 'bind' or 'interleave' policy into the argument nodemask, or |
| * initialize the argument nodemask to contain the single node for |
| * 'preferred' or 'local' policy and return 'true' to indicate presence |
| * of non-default mempolicy. |
| * |
| * We don't bother with reference counting the mempolicy [mpol_get/put] |
| * because the current task is examining it's own mempolicy and a task's |
| * mempolicy is only ever changed by the task itself. |
| * |
| * N.B., it is the caller's responsibility to free a returned nodemask. |
| */ |
| bool init_nodemask_of_mempolicy(nodemask_t *mask) |
| { |
| struct mempolicy *mempolicy; |
| int nid; |
| |
| if (!(mask && current->mempolicy)) |
| return false; |
| |
| task_lock(current); |
| mempolicy = current->mempolicy; |
| switch (mempolicy->mode) { |
| case MPOL_PREFERRED: |
| if (mempolicy->flags & MPOL_F_LOCAL) |
| nid = numa_node_id(); |
| else |
| nid = mempolicy->v.preferred_node; |
| init_nodemask_of_node(mask, nid); |
| break; |
| |
| case MPOL_BIND: |
| /* Fall through */ |
| case MPOL_INTERLEAVE: |
| *mask = mempolicy->v.nodes; |
| break; |
| |
| default: |
| BUG(); |
| } |
| task_unlock(current); |
| |
| return true; |
| } |
| #endif |
| |
| /* |
| * mempolicy_nodemask_intersects |
| * |
| * If tsk's mempolicy is "default" [NULL], return 'true' to indicate default |
| * policy. Otherwise, check for intersection between mask and the policy |
| * nodemask for 'bind' or 'interleave' policy. For 'perferred' or 'local' |
| * policy, always return true since it may allocate elsewhere on fallback. |
| * |
| * Takes task_lock(tsk) to prevent freeing of its mempolicy. |
| */ |
| bool mempolicy_nodemask_intersects(struct task_struct *tsk, |
| const nodemask_t *mask) |
| { |
| struct mempolicy *mempolicy; |
| bool ret = true; |
| |
| if (!mask) |
| return ret; |
| task_lock(tsk); |
| mempolicy = tsk->mempolicy; |
| if (!mempolicy) |
| goto out; |
| |
| switch (mempolicy->mode) { |
| case MPOL_PREFERRED: |
| /* |
| * MPOL_PREFERRED and MPOL_F_LOCAL are only preferred nodes to |
| * allocate from, they may fallback to other nodes when oom. |
| * Thus, it's possible for tsk to have allocated memory from |
| * nodes in mask. |
| */ |
| break; |
| case MPOL_BIND: |
| case MPOL_INTERLEAVE: |
| ret = nodes_intersects(mempolicy->v.nodes, *mask); |
| break; |
| default: |
| BUG(); |
| } |
| out: |
| task_unlock(tsk); |
| return ret; |
| } |
| |
| /* Allocate a page in interleaved policy. |
| Own path because it needs to do special accounting. */ |
| static struct page *alloc_page_interleave(gfp_t gfp, unsigned order, |
| unsigned nid) |
| { |
| struct zonelist *zl; |
| struct page *page; |
| |
| zl = node_zonelist(nid, gfp); |
| page = __alloc_pages(gfp, order, zl); |
| if (page && page_zone(page) == zonelist_zone(&zl->_zonerefs[0])) |
| inc_zone_page_state(page, NUMA_INTERLEAVE_HIT); |
| return page; |
| } |
| |
| /** |
| * alloc_page_vma - Allocate a page for a VMA. |
| * |
| * @gfp: |
| * %GFP_USER user allocation. |
| * %GFP_KERNEL kernel allocations, |
| * %GFP_HIGHMEM highmem/user allocations, |
| * %GFP_FS allocation should not call back into a file system. |
| * %GFP_ATOMIC don't sleep. |
| * |
| * @vma: Pointer to VMA or NULL if not available. |
| * @addr: Virtual Address of the allocation. Must be inside the VMA. |
| * |
| * This function allocates a page from the kernel page pool and applies |
| * a NUMA policy associated with the VMA or the current process. |
| * When VMA is not NULL caller must hold down_read on the mmap_sem of the |
| * mm_struct of the VMA to prevent it from going away. Should be used for |
| * all allocations for pages that will be mapped into |
| * user space. Returns NULL when no page can be allocated. |
| * |
| * Should be called with the mm_sem of the vma hold. |
| */ |
| struct page * |
| alloc_page_vma(gfp_t gfp, struct vm_area_struct *vma, unsigned long addr) |
| { |
| struct mempolicy *pol = get_vma_policy(current, vma, addr); |
| struct zonelist *zl; |
| struct page *page; |
| |
| get_mems_allowed(); |
| if (unlikely(pol->mode == MPOL_INTERLEAVE)) { |
| unsigned nid; |
| |
| nid = interleave_nid(pol, vma, addr, PAGE_SHIFT); |
| mpol_cond_put(pol); |
| page = alloc_page_interleave(gfp, 0, nid); |
| put_mems_allowed(); |
| return page; |
| } |
| zl = policy_zonelist(gfp, pol); |
| if (unlikely(mpol_needs_cond_ref(pol))) { |
| /* |
| * slow path: ref counted shared policy |
| */ |
| struct page *page = __alloc_pages_nodemask(gfp, 0, |
| zl, policy_nodemask(gfp, pol)); |
| __mpol_put(pol); |
| put_mems_allowed(); |
| return page; |
| } |
| /* |
| * fast path: default or task policy |
| */ |
| page = __alloc_pages_nodemask(gfp, 0, zl, policy_nodemask(gfp, pol)); |
| put_mems_allowed(); |
| return page; |
| } |
| |
| /** |
| * alloc_pages_current - Allocate pages. |
| * |
| * @gfp: |
| * %GFP_USER user allocation, |
| * %GFP_KERNEL kernel allocation, |
| * %GFP_HIGHMEM highmem allocation, |
| * %GFP_FS don't call back into a file system. |
| * %GFP_ATOMIC don't sleep. |
| * @order: Power of two of allocation size in pages. 0 is a single page. |
| * |
| * Allocate a page from the kernel page pool. When not in |
| * interrupt context and apply the current process NUMA policy. |
| * Returns NULL when no page can be allocated. |
| * |
| * Don't call cpuset_update_task_memory_state() unless |
| * 1) it's ok to take cpuset_sem (can WAIT), and |
| * 2) allocating for current task (not interrupt). |
| */ |
| struct page *alloc_pages_current(gfp_t gfp, unsigned order) |
| { |
| struct mempolicy *pol = current->mempolicy; |
| struct page *page; |
| |
| if (!pol || in_interrupt() || (gfp & __GFP_THISNODE)) |
| pol = &default_policy; |
| |
| get_mems_allowed(); |
| /* |
| * No reference counting needed for current->mempolicy |
| * nor system default_policy |
| */ |
| if (pol->mode == MPOL_INTERLEAVE) |
| page = alloc_page_interleave(gfp, order, interleave_nodes(pol)); |
| else |
| page = __alloc_pages_nodemask(gfp, order, |
| policy_zonelist(gfp, pol), policy_nodemask(gfp, pol)); |
| put_mems_allowed(); |
| return page; |
| } |
| EXPORT_SYMBOL(alloc_pages_current); |
| |
| /* |
| * If mpol_dup() sees current->cpuset == cpuset_being_rebound, then it |
| * rebinds the mempolicy its copying by calling mpol_rebind_policy() |
| * with the mems_allowed returned by cpuset_mems_allowed(). This |
| * keeps mempolicies cpuset relative after its cpuset moves. See |
| * further kernel/cpuset.c update_nodemask(). |
| * |
| * current's mempolicy may be rebinded by the other task(the task that changes |
| * cpuset's mems), so we needn't do rebind work for current task. |
| */ |
| |
| /* Slow path of a mempolicy duplicate */ |
| struct mempolicy *__mpol_dup(struct mempolicy *old) |
| { |
| struct mempolicy *new = kmem_cache_alloc(policy_cache, GFP_KERNEL); |
| |
| if (!new) |
| return ERR_PTR(-ENOMEM); |
| |
| /* task's mempolicy is protected by alloc_lock */ |
| if (old == current->mempolicy) { |
| task_lock(current); |
| *new = *old; |
| task_unlock(current); |
| } else |
| *new = *old; |
| |
| rcu_read_lock(); |
| if (current_cpuset_is_being_rebound()) { |
| nodemask_t mems = cpuset_mems_allowed(current); |
| if (new->flags & MPOL_F_REBINDING) |
| mpol_rebind_policy(new, &mems, MPOL_REBIND_STEP2); |
| else |
| mpol_rebind_policy(new, &mems, MPOL_REBIND_ONCE); |
| } |
| rcu_read_unlock(); |
| atomic_set(&new->refcnt, 1); |
| return new; |
| } |
| |
| /* |
| * If *frompol needs [has] an extra ref, copy *frompol to *tompol , |
| * eliminate the * MPOL_F_* flags that require conditional ref and |
| * [NOTE!!!] drop the extra ref. Not safe to reference *frompol directly |
| * after return. Use the returned value. |
| * |
| * Allows use of a mempolicy for, e.g., multiple allocations with a single |
| * policy lookup, even if the policy needs/has extra ref on lookup. |
| * shmem_readahead needs this. |
| */ |
| struct mempolicy *__mpol_cond_copy(struct mempolicy *tompol, |
| struct mempolicy *frompol) |
| { |
| if (!mpol_needs_cond_ref(frompol)) |
| return frompol; |
| |
| *tompol = *frompol; |
| tompol->flags &= ~MPOL_F_SHARED; /* copy doesn't need unref */ |
| __mpol_put(frompol); |
| return tompol; |
| } |
| |
| /* Slow path of a mempolicy comparison */ |
| int __mpol_equal(struct mempolicy *a, struct mempolicy *b) |
| { |
| if (!a || !b) |
| return 0; |
| if (a->mode != b->mode) |
| return 0; |
| if (a->flags != b->flags) |
| return 0; |
| if (mpol_store_user_nodemask(a)) |
| if (!nodes_equal(a->w.user_nodemask, b->w.user_nodemask)) |
| return 0; |
| |
| switch (a->mode) { |
| case MPOL_BIND: |
| /* Fall through */ |
| case MPOL_INTERLEAVE: |
| return nodes_equal(a->v.nodes, b->v.nodes); |
| case MPOL_PREFERRED: |
| return a->v.preferred_node == b->v.preferred_node && |
| a->flags == b->flags; |
| default: |
| BUG(); |
| return 0; |
| } |
| } |
| |
| /* |
| * Shared memory backing store policy support. |
| * |
| * Remember policies even when nobody has shared memory mapped. |
| * The policies are kept in Red-Black tree linked from the inode. |
| * They are protected by the sp->lock spinlock, which should be held |
| * for any accesses to the tree. |
| */ |
| |
| /* lookup first element intersecting start-end */ |
| /* Caller holds sp->lock */ |
| static struct sp_node * |
| sp_lookup(struct shared_policy *sp, unsigned long start, unsigned long end) |
| { |
| struct rb_node *n = sp->root.rb_node; |
| |
| while (n) { |
| struct sp_node *p = rb_entry(n, struct sp_node, nd); |
| |
| if (start >= p->end) |
| n = n->rb_right; |
| else if (end <= p->start) |
| n = n->rb_left; |
| else |
| break; |
| } |
| if (!n) |
| return NULL; |
| for (;;) { |
| struct sp_node *w = NULL; |
| struct rb_node *prev = rb_prev(n); |
| if (!prev) |
| break; |
| w = rb_entry(prev, struct sp_node, nd); |
| if (w->end <= start) |
| break; |
| n = prev; |
| } |
| return rb_entry(n, struct sp_node, nd); |
| } |
| |
| /* Insert a new shared policy into the list. */ |
| /* Caller holds sp->lock */ |
| static void sp_insert(struct shared_policy *sp, struct sp_node *new) |
| { |
| struct rb_node **p = &sp->root.rb_node; |
| struct rb_node *parent = NULL; |
| struct sp_node *nd; |
| |
| while (*p) { |
| parent = *p; |
| nd = rb_entry(parent, struct sp_node, nd); |
| if (new->start < nd->start) |
| p = &(*p)->rb_left; |
| else if (new->end > nd->end) |
| p = &(*p)->rb_right; |
| else |
| BUG(); |
| } |
| rb_link_node(&new->nd, parent, p); |
| rb_insert_color(&new->nd, &sp->root); |
| pr_debug("inserting %lx-%lx: %d\n", new->start, new->end, |
| new->policy ? new->policy->mode : 0); |
| } |
| |
| /* Find shared policy intersecting idx */ |
| struct mempolicy * |
| mpol_shared_policy_lookup(struct shared_policy *sp, unsigned long idx) |
| { |
| struct mempolicy *pol = NULL; |
| struct sp_node *sn; |
| |
| if (!sp->root.rb_node) |
| return NULL; |
| spin_lock(&sp->lock); |
| sn = sp_lookup(sp, idx, idx+1); |
| if (sn) { |
| mpol_get(sn->policy); |
| pol = sn->policy; |
| } |
| spin_unlock(&sp->lock); |
| return pol; |
| } |
| |
| static void sp_delete(struct shared_policy *sp, struct sp_node *n) |
| { |
| pr_debug("deleting %lx-l%lx\n", n->start, n->end); |
| rb_erase(&n->nd, &sp->root); |
| mpol_put(n->policy); |
| kmem_cache_free(sn_cache, n); |
| } |
| |
| static struct sp_node *sp_alloc(unsigned long start, unsigned long end, |
| struct mempolicy *pol) |
| { |
| struct sp_node *n = kmem_cache_alloc(sn_cache, GFP_KERNEL); |
| |
| if (!n) |
| return NULL; |
| n->start = start; |
| n->end = end; |
| mpol_get(pol); |
| pol->flags |= MPOL_F_SHARED; /* for unref */ |
| n->policy = pol; |
| return n; |
| } |
| |
| /* Replace a policy range. */ |
| static int shared_policy_replace(struct shared_policy *sp, unsigned long start, |
| unsigned long end, struct sp_node *new) |
| { |
| struct sp_node *n, *new2 = NULL; |
| |
| restart: |
| spin_lock(&sp->lock); |
| n = sp_lookup(sp, start, end); |
| /* Take care of old policies in the same range. */ |
| while (n && n->start < end) { |
| struct rb_node *next = rb_next(&n->nd); |
| if (n->start >= start) { |
| if (n->end <= end) |
| sp_delete(sp, n); |
| else |
| n->start = end; |
| } else { |
| /* Old policy spanning whole new range. */ |
| if (n->end > end) { |
| if (!new2) { |
| spin_unlock(&sp->lock); |
| new2 = sp_alloc(end, n->end, n->policy); |
| if (!new2) |
| return -ENOMEM; |
| goto restart; |
| } |
| n->end = start; |
| sp_insert(sp, new2); |
| new2 = NULL; |
| break; |
| } else |
| n->end = start; |
| } |
| if (!next) |
| break; |
| n = rb_entry(next, struct sp_node, nd); |
| } |
| if (new) |
| sp_insert(sp, new); |
| spin_unlock(&sp->lock); |
| if (new2) { |
| mpol_put(new2->policy); |
| kmem_cache_free(sn_cache, new2); |
| } |
| return 0; |
| } |
| |
| /** |
| * mpol_shared_policy_init - initialize shared policy for inode |
| * @sp: pointer to inode shared policy |
| * @mpol: struct mempolicy to install |
| * |
| * Install non-NULL @mpol in inode's shared policy rb-tree. |
| * On entry, the current task has a reference on a non-NULL @mpol. |
| * This must be released on exit. |
| * This is called at get_inode() calls and we can use GFP_KERNEL. |
| */ |
| void mpol_shared_policy_init(struct shared_policy *sp, struct mempolicy *mpol) |
| { |
| int ret; |
| |
| sp->root = RB_ROOT; /* empty tree == default mempolicy */ |
| spin_lock_init(&sp->lock); |
| |
| if (mpol) { |
| struct vm_area_struct pvma; |
| struct mempolicy *new; |
| NODEMASK_SCRATCH(scratch); |
| |
| if (!scratch) |
| goto put_mpol; |
| /* contextualize the tmpfs mount point mempolicy */ |
| new = mpol_new(mpol->mode, mpol->flags, &mpol->w.user_nodemask); |
| if (IS_ERR(new)) |
| goto free_scratch; /* no valid nodemask intersection */ |
| |
| task_lock(current); |
| ret = mpol_set_nodemask(new, &mpol->w.user_nodemask, scratch); |
| task_unlock(current); |
| if (ret) |
| goto put_new; |
| |
| /* Create pseudo-vma that contains just the policy */ |
| memset(&pvma, 0, sizeof(struct vm_area_struct)); |
| pvma.vm_end = TASK_SIZE; /* policy covers entire file */ |
| mpol_set_shared_policy(sp, &pvma, new); /* adds ref */ |
| |
| put_new: |
| mpol_put(new); /* drop initial ref */ |
| free_scratch: |
| NODEMASK_SCRATCH_FREE(scratch); |
| put_mpol: |
| mpol_put(mpol); /* drop our incoming ref on sb mpol */ |
| } |
| } |
| |
| int mpol_set_shared_policy(struct shared_policy *info, |
| struct vm_area_struct *vma, struct mempolicy *npol) |
| { |
| int err; |
| struct sp_node *new = NULL; |
| unsigned long sz = vma_pages(vma); |
| |
| pr_debug("set_shared_policy %lx sz %lu %d %d %lx\n", |
| vma->vm_pgoff, |
| sz, npol ? npol->mode : -1, |
| npol ? npol->flags : -1, |
| npol ? nodes_addr(npol->v.nodes)[0] : -1); |
| |
| if (npol) { |
| new = sp_alloc(vma->vm_pgoff, vma->vm_pgoff + sz, npol); |
| if (!new) |
| return -ENOMEM; |
| } |
| err = shared_policy_replace(info, vma->vm_pgoff, vma->vm_pgoff+sz, new); |
| if (err && new) |
| kmem_cache_free(sn_cache, new); |
| return err; |
| } |
| |
| /* Free a backing policy store on inode delete. */ |
| void mpol_free_shared_policy(struct shared_policy *p) |
| { |
| struct sp_node *n; |
| struct rb_node *next; |
| |
| if (!p->root.rb_node) |
| return; |
| spin_lock(&p->lock); |
| next = rb_first(&p->root); |
| while (next) { |
| n = rb_entry(next, struct sp_node, nd); |
| next = rb_next(&n->nd); |
| rb_erase(&n->nd, &p->root); |
| mpol_put(n->policy); |
| kmem_cache_free(sn_cache, n); |
| } |
| spin_unlock(&p->lock); |
| } |
| |
| /* assumes fs == KERNEL_DS */ |
| void __init numa_policy_init(void) |
| { |
| nodemask_t interleave_nodes; |
| unsigned long largest = 0; |
| int nid, prefer = 0; |
| |
| policy_cache = kmem_cache_create("numa_policy", |
| sizeof(struct mempolicy), |
| 0, SLAB_PANIC, NULL); |
| |
| sn_cache = kmem_cache_create("shared_policy_node", |
| sizeof(struct sp_node), |
| 0, SLAB_PANIC, NULL); |
| |
| /* |
| * Set interleaving policy for system init. Interleaving is only |
| * enabled across suitably sized nodes (default is >= 16MB), or |
| * fall back to the largest node if they're all smaller. |
| */ |
| nodes_clear(interleave_nodes); |
| for_each_node_state(nid, N_HIGH_MEMORY) { |
| unsigned long total_pages = node_present_pages(nid); |
| |
| /* Preserve the largest node */ |
| if (largest < total_pages) { |
| largest = total_pages; |
| prefer = nid; |
| } |
| |
| /* Interleave this node? */ |
| if ((total_pages << PAGE_SHIFT) >= (16 << 20)) |
| node_set(nid, interleave_nodes); |
| } |
| |
| /* All too small, use the largest */ |
| if (unlikely(nodes_empty(interleave_nodes))) |
| node_set(prefer, interleave_nodes); |
| |
| if (do_set_mempolicy(MPOL_INTERLEAVE, 0, &interleave_nodes)) |
| printk("numa_policy_init: interleaving failed\n"); |
| } |
| |
| /* Reset policy of current process to default */ |
| void numa_default_policy(void) |
| { |
| do_set_mempolicy(MPOL_DEFAULT, 0, NULL); |
| } |
| |
| /* |
| * Parse and format mempolicy from/to strings |
| */ |
| |
| /* |
| * "local" is pseudo-policy: MPOL_PREFERRED with MPOL_F_LOCAL flag |
| * Used only for mpol_parse_str() and mpol_to_str() |
| */ |
| #define MPOL_LOCAL MPOL_MAX |
| static const char * const policy_modes[] = |
| { |
| [MPOL_DEFAULT] = "default", |
| [MPOL_PREFERRED] = "prefer", |
| [MPOL_BIND] = "bind", |
| [MPOL_INTERLEAVE] = "interleave", |
| [MPOL_LOCAL] = "local" |
| }; |
| |
| |
| #ifdef CONFIG_TMPFS |
| /** |
| * mpol_parse_str - parse string to mempolicy |
| * @str: string containing mempolicy to parse |
| * @mpol: pointer to struct mempolicy pointer, returned on success. |
| * @no_context: flag whether to "contextualize" the mempolicy |
| * |
| * Format of input: |
| * <mode>[=<flags>][:<nodelist>] |
| * |
| * if @no_context is true, save the input nodemask in w.user_nodemask in |
| * the returned mempolicy. This will be used to "clone" the mempolicy in |
| * a specific context [cpuset] at a later time. Used to parse tmpfs mpol |
| * mount option. Note that if 'static' or 'relative' mode flags were |
| * specified, the input nodemask will already have been saved. Saving |
| * it again is redundant, but safe. |
| * |
| * On success, returns 0, else 1 |
| */ |
| int mpol_parse_str(char *str, struct mempolicy **mpol, int no_context) |
| { |
| struct mempolicy *new = NULL; |
| unsigned short mode; |
| unsigned short uninitialized_var(mode_flags); |
| nodemask_t nodes; |
| char *nodelist = strchr(str, ':'); |
| char *flags = strchr(str, '='); |
| int err = 1; |
| |
| if (nodelist) { |
| /* NUL-terminate mode or flags string */ |
| *nodelist++ = '\0'; |
| if (nodelist_parse(nodelist, nodes)) |
| goto out; |
| if (!nodes_subset(nodes, node_states[N_HIGH_MEMORY])) |
| goto out; |
| } else |
| nodes_clear(nodes); |
| |
| if (flags) |
| *flags++ = '\0'; /* terminate mode string */ |
| |
| for (mode = 0; mode <= MPOL_LOCAL; mode++) { |
| if (!strcmp(str, policy_modes[mode])) { |
| break; |
| } |
| } |
| if (mode > MPOL_LOCAL) |
| goto out; |
| |
| switch (mode) { |
| case MPOL_PREFERRED: |
| /* |
| * Insist on a nodelist of one node only |
| */ |
| if (nodelist) { |
| char *rest = nodelist; |
| while (isdigit(*rest)) |
| rest++; |
| if (*rest) |
| goto out; |
| } |
| break; |
| case MPOL_INTERLEAVE: |
| /* |
| * Default to online nodes with memory if no nodelist |
| */ |
| if (!nodelist) |
| nodes = node_states[N_HIGH_MEMORY]; |
| break; |
| case MPOL_LOCAL: |
| /* |
| * Don't allow a nodelist; mpol_new() checks flags |
| */ |
| if (nodelist) |
| goto out; |
| mode = MPOL_PREFERRED; |
| break; |
| case MPOL_DEFAULT: |
| /* |
| * Insist on a empty nodelist |
| */ |
| if (!nodelist) |
| err = 0; |
| goto out; |
| case MPOL_BIND: |
| /* |
| * Insist on a nodelist |
| */ |
| if (!nodelist) |
| goto out; |
| } |
| |
| mode_flags = 0; |
| if (flags) { |
| /* |
| * Currently, we only support two mutually exclusive |
| * mode flags. |
| */ |
| if (!strcmp(flags, "static")) |
| mode_flags |= MPOL_F_STATIC_NODES; |
| else if (!strcmp(flags, "relative")) |
| mode_flags |= MPOL_F_RELATIVE_NODES; |
| else |
| goto out; |
| } |
| |
| new = mpol_new(mode, mode_flags, &nodes); |
| if (IS_ERR(new)) |
| goto out; |
| |
| if (no_context) { |
| /* save for contextualization */ |
| new->w.user_nodemask = nodes; |
| } else { |
| int ret; |
| NODEMASK_SCRATCH(scratch); |
| if (scratch) { |
| task_lock(current); |
| ret = mpol_set_nodemask(new, &nodes, scratch); |
| task_unlock(current); |
| } else |
| ret = -ENOMEM; |
| NODEMASK_SCRATCH_FREE(scratch); |
| if (ret) { |
| mpol_put(new); |
| goto out; |
| } |
| } |
| err = 0; |
| |
| out: |
| /* Restore string for error message */ |
| if (nodelist) |
| *--nodelist = ':'; |
| if (flags) |
| *--flags = '='; |
| if (!err) |
| *mpol = new; |
| return err; |
| } |
| #endif /* CONFIG_TMPFS */ |
| |
| /** |
| * mpol_to_str - format a mempolicy structure for printing |
| * @buffer: to contain formatted mempolicy string |
| * @maxlen: length of @buffer |
| * @pol: pointer to mempolicy to be formatted |
| * @no_context: "context free" mempolicy - use nodemask in w.user_nodemask |
| * |
| * Convert a mempolicy into a string. |
| * Returns the number of characters in buffer (if positive) |
| * or an error (negative) |
| */ |
| int mpol_to_str(char *buffer, int maxlen, struct mempolicy *pol, int no_context) |
| { |
| char *p = buffer; |
| int l; |
| nodemask_t nodes; |
| unsigned short mode; |
| unsigned short flags = pol ? pol->flags : 0; |
| |
| /* |
| * Sanity check: room for longest mode, flag and some nodes |
| */ |
| VM_BUG_ON(maxlen < strlen("interleave") + strlen("relative") + 16); |
| |
| if (!pol || pol == &default_policy) |
| mode = MPOL_DEFAULT; |
| else |
| mode = pol->mode; |
| |
| switch (mode) { |
| case MPOL_DEFAULT: |
| nodes_clear(nodes); |
| break; |
| |
| case MPOL_PREFERRED: |
| nodes_clear(nodes); |
| if (flags & MPOL_F_LOCAL) |
| mode = MPOL_LOCAL; /* pseudo-policy */ |
| else |
| node_set(pol->v.preferred_node, nodes); |
| break; |
| |
| case MPOL_BIND: |
| /* Fall through */ |
| case MPOL_INTERLEAVE: |
| if (no_context) |
| nodes = pol->w.user_nodemask; |
| else |
| nodes = pol->v.nodes; |
| break; |
| |
| default: |
| BUG(); |
| } |
| |
| l = strlen(policy_modes[mode]); |
| if (buffer + maxlen < p + l + 1) |
| return -ENOSPC; |
| |
| strcpy(p, policy_modes[mode]); |
| p += l; |
| |
| if (flags & MPOL_MODE_FLAGS) { |
| if (buffer + maxlen < p + 2) |
| return -ENOSPC; |
| *p++ = '='; |
| |
| /* |
| * Currently, the only defined flags are mutually exclusive |
| */ |
| if (flags & MPOL_F_STATIC_NODES) |
| p += snprintf(p, buffer + maxlen - p, "static"); |
| else if (flags & MPOL_F_RELATIVE_NODES) |
| p += snprintf(p, buffer + maxlen - p, "relative"); |
| } |
| |
| if (!nodes_empty(nodes)) { |
| if (buffer + maxlen < p + 2) |
| return -ENOSPC; |
| *p++ = ':'; |
| p += nodelist_scnprintf(p, buffer + maxlen - p, nodes); |
| } |
| return p - buffer; |
| } |
| |
| struct numa_maps { |
| unsigned long pages; |
| unsigned long anon; |
| unsigned long active; |
| unsigned long writeback; |
| unsigned long mapcount_max; |
| unsigned long dirty; |
| unsigned long swapcache; |
| unsigned long node[MAX_NUMNODES]; |
| }; |
| |
| static void gather_stats(struct page *page, void *private, int pte_dirty) |
| { |
| struct numa_maps *md = private; |
| int count = page_mapcount(page); |
| |
| md->pages++; |
| if (pte_dirty || PageDirty(page)) |
| md->dirty++; |
| |
| if (PageSwapCache(page)) |
| md->swapcache++; |
| |
| if (PageActive(page) || PageUnevictable(page)) |
| md->active++; |
| |
| if (PageWriteback(page)) |
| md->writeback++; |
| |
| if (PageAnon(page)) |
| md->anon++; |
| |
| if (count > md->mapcount_max) |
| md->mapcount_max = count; |
| |
| md->node[page_to_nid(page)]++; |
| } |
| |
| #ifdef CONFIG_HUGETLB_PAGE |
| static void check_huge_range(struct vm_area_struct *vma, |
| unsigned long start, unsigned long end, |
| struct numa_maps *md) |
| { |
| unsigned long addr; |
| struct page *page; |
| struct hstate *h = hstate_vma(vma); |
| unsigned long sz = huge_page_size(h); |
| |
| for (addr = start; addr < end; addr += sz) { |
| pte_t *ptep = huge_pte_offset(vma->vm_mm, |
| addr & huge_page_mask(h)); |
| pte_t pte; |
| |
| if (!ptep) |
| continue; |
| |
| pte = *ptep; |
| if (pte_none(pte)) |
| continue; |
| |
| page = pte_page(pte); |
| if (!page) |
| continue; |
| |
| gather_stats(page, md, pte_dirty(*ptep)); |
| } |
| } |
| #else |
| static inline void check_huge_range(struct vm_area_struct *vma, |
| unsigned long start, unsigned long end, |
| struct numa_maps *md) |
| { |
| } |
| #endif |
| |
| /* |
| * Display pages allocated per node and memory policy via /proc. |
| */ |
| int show_numa_map(struct seq_file *m, void *v) |
| { |
| struct proc_maps_private *priv = m->private; |
| struct vm_area_struct *vma = v; |
| struct numa_maps *md; |
| struct file *file = vma->vm_file; |
| struct mm_struct *mm = vma->vm_mm; |
| struct mempolicy *pol; |
| int n; |
| char buffer[50]; |
| |
| if (!mm) |
| return 0; |
| |
| md = kzalloc(sizeof(struct numa_maps), GFP_KERNEL); |
| if (!md) |
| return 0; |
| |
| pol = get_vma_policy(priv->task, vma, vma->vm_start); |
| mpol_to_str(buffer, sizeof(buffer), pol, 0); |
| mpol_cond_put(pol); |
| |
| seq_printf(m, "%08lx %s", vma->vm_start, buffer); |
| |
| if (file) { |
| seq_printf(m, " file="); |
| seq_path(m, &file->f_path, "\n\t= "); |
| } else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) { |
| seq_printf(m, " heap"); |
| } else if (vma->vm_start <= mm->start_stack && |
| vma->vm_end >= mm->start_stack) { |
| seq_printf(m, " stack"); |
| } |
| |
| if (is_vm_hugetlb_page(vma)) { |
| check_huge_range(vma, vma->vm_start, vma->vm_end, md); |
| seq_printf(m, " huge"); |
| } else { |
| check_pgd_range(vma, vma->vm_start, vma->vm_end, |
| &node_states[N_HIGH_MEMORY], MPOL_MF_STATS, md); |
| } |
| |
| if (!md->pages) |
| goto out; |
| |
| if (md->anon) |
| seq_printf(m," anon=%lu",md->anon); |
| |
| if (md->dirty) |
| seq_printf(m," dirty=%lu",md->dirty); |
| |
| if (md->pages != md->anon && md->pages != md->dirty) |
| seq_printf(m, " mapped=%lu", md->pages); |
| |
| if (md->mapcount_max > 1) |
| seq_printf(m, " mapmax=%lu", md->mapcount_max); |
| |
| if (md->swapcache) |
| seq_printf(m," swapcache=%lu", md->swapcache); |
| |
| if (md->active < md->pages && !is_vm_hugetlb_page(vma)) |
| seq_printf(m," active=%lu", md->active); |
| |
| if (md->writeback) |
| seq_printf(m," writeback=%lu", md->writeback); |
| |
| for_each_node_state(n, N_HIGH_MEMORY) |
| if (md->node[n]) |
| seq_printf(m, " N%d=%lu", n, md->node[n]); |
| out: |
| seq_putc(m, '\n'); |
| kfree(md); |
| |
| if (m->count < m->size) |
| m->version = (vma != priv->tail_vma) ? vma->vm_start : 0; |
| return 0; |
| } |