X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=mm%2Fmempolicy.c;h=f11fdad06204c01f447d4bd7053ac930b7b636a4;hb=4f0ddfdffc8bef3a5eb9154734d68a6053194948;hp=b23492ee3e5072dbc74814bf06e9635de7f16422;hpb=b6dff3ec5e116e3af6f537d4caedcad6b9e5082a;p=safe%2Fjmp%2Flinux-2.6 diff --git a/mm/mempolicy.c b/mm/mempolicy.c index b23492e..f11fdad 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -89,6 +89,7 @@ #include #include #include +#include #include #include @@ -182,13 +183,58 @@ static int mpol_new_bind(struct mempolicy *pol, const nodemask_t *nodes) return 0; } -/* Create a new policy */ +/* + * 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; - nodemask_t cpuset_context_nmask; - int ret; pr_debug("setting mode %d flags %d nodes[0] %lx\n", mode, flags, nodes ? nodes_addr(*nodes)[0] : -1); @@ -210,7 +256,6 @@ static struct mempolicy *mpol_new(unsigned short mode, unsigned short flags, if (((flags & MPOL_F_STATIC_NODES) || (flags & MPOL_F_RELATIVE_NODES))) return ERR_PTR(-EINVAL); - nodes = NULL; /* flag local alloc */ } } else if (nodes_empty(*nodes)) return ERR_PTR(-EINVAL); @@ -221,30 +266,6 @@ static struct mempolicy *mpol_new(unsigned short mode, unsigned short flags, policy->mode = mode; policy->flags = flags; - if (nodes) { - /* - * cpuset related setup doesn't apply to local allocation - */ - cpuset_update_task_memory_state(); - if (flags & MPOL_F_RELATIVE_NODES) - mpol_relative_nodemask(&cpuset_context_nmask, nodes, - &cpuset_current_mems_allowed); - else - nodes_and(cpuset_context_nmask, *nodes, - cpuset_current_mems_allowed); - if (mpol_store_user_nodemask(policy)) - policy->w.user_nodemask = *nodes; - else - policy->w.cpuset_mems_allowed = - cpuset_mems_allowed(current); - } - - ret = mpol_ops[mode].create(policy, - nodes ? &cpuset_context_nmask : NULL); - if (ret < 0) { - kmem_cache_free(policy_cache, policy); - return ERR_PTR(ret); - } return policy; } @@ -324,6 +345,8 @@ static void mpol_rebind_policy(struct mempolicy *pol, /* * 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) @@ -489,12 +512,6 @@ check_range(struct mm_struct *mm, unsigned long start, unsigned long end, int err; struct vm_area_struct *first, *vma, *prev; - if (flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) { - - err = migrate_prep(); - if (err) - return ERR_PTR(err); - } first = find_vma(mm, start); if (!first) @@ -606,13 +623,19 @@ static void mpol_set_task_struct_flag(void) static long do_set_mempolicy(unsigned short mode, unsigned short flags, nodemask_t *nodes) { - struct mempolicy *new; + struct mempolicy *new, *old; struct mm_struct *mm = current->mm; + NODEMASK_SCRATCH(scratch); + int ret; - new = mpol_new(mode, flags, nodes); - if (IS_ERR(new)) - return PTR_ERR(new); + 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. @@ -621,20 +644,36 @@ static long do_set_mempolicy(unsigned short mode, unsigned short flags, */ if (mm) down_write(&mm->mmap_sem); - mpol_put(current->mempolicy); + 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); - return 0; + 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) { @@ -680,7 +719,6 @@ static long do_get_mempolicy(int *policy, nodemask_t *nmask, struct vm_area_struct *vma = NULL; struct mempolicy *pol = current->mempolicy; - cpuset_update_task_memory_state(); if (flags & ~(unsigned long)(MPOL_F_NODE|MPOL_F_ADDR|MPOL_F_MEMS_ALLOWED)) return -EINVAL; @@ -689,7 +727,9 @@ static long do_get_mempolicy(int *policy, nodemask_t *nmask, 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; } @@ -744,8 +784,11 @@ static long do_get_mempolicy(int *policy, nodemask_t *nmask, } err = 0; - if (nmask) + if (nmask) { + task_lock(current); get_policy_nodemask(pol, nmask); + task_unlock(current); + } out: mpol_cond_put(pol); @@ -767,13 +810,15 @@ static void migrate_page_add(struct page *page, struct list_head *pagelist, 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_node(node, GFP_HIGHUSER_MOVABLE, 0); + return alloc_pages_exact_node(node, GFP_HIGHUSER_MOVABLE, 0); } /* @@ -809,9 +854,13 @@ 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 = 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); @@ -974,7 +1023,28 @@ static long do_mbind(unsigned long start, unsigned long len, start, start + len, mode, mode_flags, nmask ? nodes_addr(*nmask)[0] : -1); - down_write(&mm->mmap_sem); + 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); @@ -990,9 +1060,11 @@ static long do_mbind(unsigned long start, unsigned long len, 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; } @@ -1064,10 +1136,9 @@ static int copy_nodes_to_user(unsigned long __user *mask, unsigned long maxnode, return copy_to_user(mask, nodes_addr(*nodes), copy) ? -EFAULT : 0; } -asmlinkage long sys_mbind(unsigned long start, unsigned long len, - unsigned long mode, - unsigned long __user *nmask, unsigned long maxnode, - unsigned flags) +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; @@ -1087,8 +1158,8 @@ asmlinkage long sys_mbind(unsigned long start, unsigned long len, } /* Set the process memory policy */ -asmlinkage long sys_set_mempolicy(int mode, unsigned long __user *nmask, - unsigned long maxnode) +SYSCALL_DEFINE3(set_mempolicy, int, mode, unsigned long __user *, nmask, + unsigned long, maxnode) { int err; nodemask_t nodes; @@ -1106,11 +1177,11 @@ asmlinkage long sys_set_mempolicy(int mode, unsigned long __user *nmask, return do_set_mempolicy(mode, flags, &nodes); } -asmlinkage long sys_migrate_pages(pid_t pid, unsigned long maxnode, - const unsigned long __user *old_nodes, - const unsigned long __user *new_nodes) +SYSCALL_DEFINE4(migrate_pages, pid_t, pid, unsigned long, maxnode, + const unsigned long __user *, old_nodes, + const unsigned long __user *, new_nodes) { - struct cred *cred, *tcred; + const struct cred *cred = current_cred(), *tcred; struct mm_struct *mm; struct task_struct *task; nodemask_t old; @@ -1145,14 +1216,16 @@ asmlinkage long sys_migrate_pages(pid_t pid, unsigned long maxnode, * capabilities, superuser privileges or the same * userid as the target process. */ - cred = current->cred; - tcred = task->cred; + 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? */ @@ -1179,10 +1252,9 @@ out: /* Retrieve NUMA policy */ -asmlinkage long sys_get_mempolicy(int __user *policy, - unsigned long __user *nmask, - unsigned long maxnode, - unsigned long addr, unsigned long flags) +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); @@ -1496,6 +1568,53 @@ struct zonelist *huge_zonelist(struct vm_area_struct *vma, unsigned long addr, } 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; + + 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(); + } + + return true; +} #endif /* Allocate a page in interleaved policy. @@ -1541,8 +1660,6 @@ 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; - cpuset_update_task_memory_state(); - if (unlikely(pol->mode == MPOL_INTERLEAVE)) { unsigned nid; @@ -1589,8 +1706,6 @@ struct page *alloc_pages_current(gfp_t gfp, unsigned order) { struct mempolicy *pol = current->mempolicy; - if ((gfp & __GFP_WAIT) && !in_interrupt()) - cpuset_update_task_memory_state(); if (!pol || in_interrupt() || (gfp & __GFP_THISNODE)) pol = &default_policy; @@ -1847,27 +1962,46 @@ restart: * 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) + return; /* contextualize the tmpfs mount point mempolicy */ new = mpol_new(mpol->mode, mpol->flags, &mpol->w.user_nodemask); - mpol_put(mpol); /* drop our ref on sb mpol */ - if (IS_ERR(new)) + if (IS_ERR(new)) { + mpol_put(mpol); /* drop our ref on sb mpol */ + NODEMASK_SCRATCH_FREE(scratch); return; /* no valid nodemask intersection */ + } + + task_lock(current); + ret = mpol_set_nodemask(new, &mpol->w.user_nodemask, scratch); + task_unlock(current); + mpol_put(mpol); /* drop our ref on sb mpol */ + if (ret) { + NODEMASK_SCRATCH_FREE(scratch); + mpol_put(new); + return; + } /* 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 */ mpol_put(new); /* drop initial ref */ + NODEMASK_SCRATCH_FREE(scratch); } } @@ -2082,8 +2216,24 @@ int mpol_parse_str(char *str, struct mempolicy **mpol, int no_context) new = mpol_new(mode, mode_flags, &nodes); if (IS_ERR(new)) err = 1; - else if (no_context) - new->w.user_nodemask = nodes; /* save for contextualization */ + 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) { + err = 1; + mpol_put(new); + } else if (no_context) { + /* save for contextualization */ + new->w.user_nodemask = nodes; + } + } out: /* Restore string for error message */