Merge branch 'linus' into timers/nohz

5 files changed, 152 insertions, 97 deletions

diff --git a/fs/proc/array.c b/fs/proc/array.c
index 9e3b8c33c24b..797d775e0354 100644
--- a/fs/proc/array.c
+++ b/fs/proc/array.c
@@ -288,7 +288,7 @@ static void render_cap_t(struct seq_file *m, const char *header,
         seq_printf(m, "%s", header);
         CAP_FOR_EACH_U32(__capi) {
                 seq_printf(m, "%08x",
-                           a->cap[(_LINUX_CAPABILITY_U32S-1) - __capi]);
+                           a->cap[(_KERNEL_CAPABILITY_U32S-1) - __capi]);
         }
         seq_printf(m, "\n");
 }
diff --git a/fs/proc/base.c b/fs/proc/base.c
index c447e0743a3c..58c3e6a8e15e 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -127,6 +127,25 @@ struct pid_entry {
                 NULL, &proc_single_file_operations,     \
                 { .proc_show = &proc_##OTYPE } )
 
+/*
+ * Count the number of hardlinks for the pid_entry table, excluding the .
+ * and .. links.
+ */
+static unsigned int pid_entry_count_dirs(const struct pid_entry *entries,
+        unsigned int n)
+{
+        unsigned int i;
+        unsigned int count;
+
+        count = 0;
+        for (i = 0; i < n; ++i) {
+                if (S_ISDIR(entries[i].mode))
+                        ++count;
+        }
+
+        return count;
+}
+
 int maps_protect;
 EXPORT_SYMBOL(maps_protect);
 
@@ -214,7 +233,7 @@ static int check_mem_permission(struct task_struct *task)
          */
         if (task->parent == current && (task->ptrace & PT_PTRACED) &&
             task_is_stopped_or_traced(task) &&
-            ptrace_may_attach(task))
+            ptrace_may_access(task, PTRACE_MODE_ATTACH))
                 return 0;
 
         /*
@@ -232,7 +251,8 @@ struct mm_struct *mm_for_maps(struct task_struct *task)
         task_lock(task);
         if (task->mm != mm)
                 goto out;
-        if (task->mm != current->mm && __ptrace_may_attach(task) < 0)
+        if (task->mm != current->mm &&
+            __ptrace_may_access(task, PTRACE_MODE_READ) < 0)
                 goto out;
         task_unlock(task);
         return mm;
@@ -499,7 +519,7 @@ static int proc_fd_access_allowed(struct inode *inode)
          */
         task = get_proc_task(inode);
         if (task) {
-                allowed = ptrace_may_attach(task);
+                allowed = ptrace_may_access(task, PTRACE_MODE_READ);
                 put_task_struct(task);
         }
         return allowed;
@@ -885,7 +905,7 @@ static ssize_t environ_read(struct file *file, char __user *buf,
         if (!task)
                 goto out_no_task;
 
-        if (!ptrace_may_attach(task))
+        if (!ptrace_may_access(task, PTRACE_MODE_READ))
                 goto out;
 
         ret = -ENOMEM;
@@ -2585,10 +2605,9 @@ static struct dentry *proc_pid_instantiate(struct inode *dir,
         inode->i_op = &proc_tgid_base_inode_operations;
         inode->i_fop = &proc_tgid_base_operations;
         inode->i_flags|=S_IMMUTABLE;
-        inode->i_nlink = 5;
-#ifdef CONFIG_SECURITY
-        inode->i_nlink += 1;
-#endif
+
+        inode->i_nlink = 2 + pid_entry_count_dirs(tgid_base_stuff,
+                ARRAY_SIZE(tgid_base_stuff));
 
         dentry->d_op = &pid_dentry_operations;
 
@@ -2816,10 +2835,9 @@ static struct dentry *proc_task_instantiate(struct inode *dir,
         inode->i_op = &proc_tid_base_inode_operations;
         inode->i_fop = &proc_tid_base_operations;
         inode->i_flags|=S_IMMUTABLE;
-        inode->i_nlink = 4;
-#ifdef CONFIG_SECURITY
-        inode->i_nlink += 1;
-#endif
+
+        inode->i_nlink = 2 + pid_entry_count_dirs(tid_base_stuff,
+                ARRAY_SIZE(tid_base_stuff));
 
         dentry->d_op = &pid_dentry_operations;
 
diff --git a/fs/proc/proc_misc.c b/fs/proc/proc_misc.c
index 32dc14cd8900..c652d469dc08 100644
--- a/fs/proc/proc_misc.c
+++ b/fs/proc/proc_misc.c
@@ -123,6 +123,11 @@ static int uptime_read_proc(char *page, char **start, off_t off,
         return proc_calc_metrics(page, start, off, count, eof, len);
 }
 
+int __attribute__((weak)) arch_report_meminfo(char *page)
+{
+        return 0;
+}
+
 static int meminfo_read_proc(char *page, char **start, off_t off,
                                  int count, int *eof, void *data)
 {
@@ -221,6 +226,8 @@ static int meminfo_read_proc(char *page, char **start, off_t off,
 
                 len += hugetlb_report_meminfo(page + len);
 
+        len += arch_report_meminfo(page + len);
+
         return proc_calc_metrics(page, start, off, count, eof, len);
 #undef K
 }
@@ -472,6 +479,13 @@ static const struct file_operations proc_vmalloc_operations = {
 };
 #endif
 
+#ifndef arch_irq_stat_cpu
+#define arch_irq_stat_cpu(cpu) 0
+#endif
+#ifndef arch_irq_stat
+#define arch_irq_stat() 0
+#endif
+
 static int show_stat(struct seq_file *p, void *v)
 {
         int i;
@@ -509,7 +523,9 @@ static int show_stat(struct seq_file *p, void *v)
                         sum += temp;
                         per_irq_sum[j] += temp;
                 }
+                sum += arch_irq_stat_cpu(i);
         }
+        sum += arch_irq_stat();
 
         seq_printf(p, "cpu  %llu %llu %llu %llu %llu %llu %llu %llu %llu\n",
                 (unsigned long long)cputime64_to_clock_t(user),
@@ -716,7 +732,7 @@ static ssize_t kpagecount_read(struct file *file, char __user *buf,
         pfn = src / KPMSIZE;
         count = min_t(size_t, count, (max_pfn * KPMSIZE) - src);
         if (src & KPMMASK || count & KPMMASK)
-                return -EIO;
+                return -EINVAL;
 
         while (count > 0) {
                 ppage = NULL;
@@ -726,7 +742,7 @@ static ssize_t kpagecount_read(struct file *file, char __user *buf,
                 if (!ppage)
                         pcount = 0;
                 else
-                        pcount = atomic_read(&ppage->_count);
+                        pcount = page_mapcount(ppage);
 
                 if (put_user(pcount, out++)) {
                         ret = -EFAULT;
@@ -782,7 +798,7 @@ static ssize_t kpageflags_read(struct file *file, char __user *buf,
         pfn = src / KPMSIZE;
         count = min_t(unsigned long, count, (max_pfn * KPMSIZE) - src);
         if (src & KPMMASK || count & KPMMASK)
-                return -EIO;
+                return -EINVAL;
 
         while (count > 0) {
                 ppage = NULL;
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 88717c0f941b..164bd9f9ede3 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -210,7 +210,7 @@ static int show_map(struct seq_file *m, void *v)
         dev_t dev = 0;
         int len;
 
-        if (maps_protect && !ptrace_may_attach(task))
+        if (maps_protect && !ptrace_may_access(task, PTRACE_MODE_READ))
                 return -EACCES;
 
         if (file) {
@@ -315,9 +315,9 @@ struct mem_size_stats {
 };
 
 static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
-                           void *private)
+                           struct mm_walk *walk)
 {
-        struct mem_size_stats *mss = private;
+        struct mem_size_stats *mss = walk->private;
         struct vm_area_struct *vma = mss->vma;
         pte_t *pte, ptent;
         spinlock_t *ptl;
@@ -365,19 +365,21 @@ static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
         return 0;
 }
 
-static struct mm_walk smaps_walk = { .pmd_entry = smaps_pte_range };
-
 static int show_smap(struct seq_file *m, void *v)
 {
         struct vm_area_struct *vma = v;
         struct mem_size_stats mss;
         int ret;
+        struct mm_walk smaps_walk = {
+                .pmd_entry = smaps_pte_range,
+                .mm = vma->vm_mm,
+                .private = &mss,
+        };
 
         memset(&mss, 0, sizeof mss);
         mss.vma = vma;
         if (vma->vm_mm && !is_vm_hugetlb_page(vma))
-                walk_page_range(vma->vm_mm, vma->vm_start, vma->vm_end,
-                                &smaps_walk, &mss);
+                walk_page_range(vma->vm_start, vma->vm_end, &smaps_walk);
 
         ret = show_map(m, v);
         if (ret)
@@ -426,9 +428,9 @@ const struct file_operations proc_smaps_operations = {
 };
 
 static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr,
-                                unsigned long end, void *private)
+                                unsigned long end, struct mm_walk *walk)
 {
-        struct vm_area_struct *vma = private;
+        struct vm_area_struct *vma = walk->private;
         pte_t *pte, ptent;
         spinlock_t *ptl;
         struct page *page;
@@ -452,8 +454,6 @@ static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr,
         return 0;
 }
 
-static struct mm_walk clear_refs_walk = { .pmd_entry = clear_refs_pte_range };
-
 static ssize_t clear_refs_write(struct file *file, const char __user *buf,
                                 size_t count, loff_t *ppos)
 {
@@ -476,11 +476,17 @@ static ssize_t clear_refs_write(struct file *file, const char __user *buf,
                 return -ESRCH;
         mm = get_task_mm(task);
         if (mm) {
+                struct mm_walk clear_refs_walk = {
+                        .pmd_entry = clear_refs_pte_range,
+                        .mm = mm,
+                };
                 down_read(&mm->mmap_sem);
-                for (vma = mm->mmap; vma; vma = vma->vm_next)
+                for (vma = mm->mmap; vma; vma = vma->vm_next) {
+                        clear_refs_walk.private = vma;
                         if (!is_vm_hugetlb_page(vma))
-                                walk_page_range(mm, vma->vm_start, vma->vm_end,
-                                                &clear_refs_walk, vma);
+                                walk_page_range(vma->vm_start, vma->vm_end,
+                                                &clear_refs_walk);
+                }
                 flush_tlb_mm(mm);
                 up_read(&mm->mmap_sem);
                 mmput(mm);
@@ -496,7 +502,7 @@ const struct file_operations proc_clear_refs_operations = {
 };
 
 struct pagemapread {
-        char __user *out, *end;
+        u64 __user *out, *end;
 };
 
 #define PM_ENTRY_BYTES      sizeof(u64)
@@ -519,28 +525,18 @@ struct pagemapread {
 static int add_to_pagemap(unsigned long addr, u64 pfn,
                           struct pagemapread *pm)
 {
-        /*
-         * Make sure there's room in the buffer for an
-         * entire entry.  Otherwise, only copy part of
-         * the pfn.
-         */
-        if (pm->out + PM_ENTRY_BYTES >= pm->end) {
-                if (copy_to_user(pm->out, &pfn, pm->end - pm->out))
-                        return -EFAULT;
-                pm->out = pm->end;
-                return PM_END_OF_BUFFER;
-        }
-
         if (put_user(pfn, pm->out))
                 return -EFAULT;
-        pm->out += PM_ENTRY_BYTES;
+        pm->out++;
+        if (pm->out >= pm->end)
+                return PM_END_OF_BUFFER;
         return 0;
 }
 
 static int pagemap_pte_hole(unsigned long start, unsigned long end,
-                                void *private)
+                                struct mm_walk *walk)
 {
-        struct pagemapread *pm = private;
+        struct pagemapread *pm = walk->private;
         unsigned long addr;
         int err = 0;
         for (addr = start; addr < end; addr += PAGE_SIZE) {
@@ -557,24 +553,45 @@ static u64 swap_pte_to_pagemap_entry(pte_t pte)
         return swp_type(e) | (swp_offset(e) << MAX_SWAPFILES_SHIFT);
 }
 
+static unsigned long pte_to_pagemap_entry(pte_t pte)
+{
+        unsigned long pme = 0;
+        if (is_swap_pte(pte))
+                pme = PM_PFRAME(swap_pte_to_pagemap_entry(pte))
+                        | PM_PSHIFT(PAGE_SHIFT) | PM_SWAP;
+        else if (pte_present(pte))
+                pme = PM_PFRAME(pte_pfn(pte))
+                        | PM_PSHIFT(PAGE_SHIFT) | PM_PRESENT;
+        return pme;
+}
+
 static int pagemap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
-                             void *private)
+                             struct mm_walk *walk)
 {
-        struct pagemapread *pm = private;
+        struct vm_area_struct *vma;
+        struct pagemapread *pm = walk->private;
         pte_t *pte;
         int err = 0;
 
+        /* find the first VMA at or above 'addr' */
+        vma = find_vma(walk->mm, addr);
         for (; addr != end; addr += PAGE_SIZE) {
                 u64 pfn = PM_NOT_PRESENT;
-                pte = pte_offset_map(pmd, addr);
-                if (is_swap_pte(*pte))
-                        pfn = PM_PFRAME(swap_pte_to_pagemap_entry(*pte))
-                                | PM_PSHIFT(PAGE_SHIFT) | PM_SWAP;
-                else if (pte_present(*pte))
-                        pfn = PM_PFRAME(pte_pfn(*pte))
-                                | PM_PSHIFT(PAGE_SHIFT) | PM_PRESENT;
-                /* unmap so we're not in atomic when we copy to userspace */
-                pte_unmap(pte);
+
+                /* check to see if we've left 'vma' behind
+                 * and need a new, higher one */
+                if (vma && (addr >= vma->vm_end))
+                        vma = find_vma(walk->mm, addr);
+
+                /* check that 'vma' actually covers this address,
+                 * and that it isn't a huge page vma */
+                if (vma && (vma->vm_start <= addr) &&
+                    !is_vm_hugetlb_page(vma)) {
+                        pte = pte_offset_map(pmd, addr);
+                        pfn = pte_to_pagemap_entry(*pte);
+                        /* unmap before userspace copy */
+                        pte_unmap(pte);
+                }
                 err = add_to_pagemap(addr, pfn, pm);
                 if (err)
                         return err;
@@ -585,11 +602,6 @@ static int pagemap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
         return err;
 }
 
-static struct mm_walk pagemap_walk = {
-        .pmd_entry = pagemap_pte_range,
-        .pte_hole = pagemap_pte_hole
-};
-
 /*
  * /proc/pid/pagemap - an array mapping virtual pages to pfns
  *
@@ -624,17 +636,22 @@ static ssize_t pagemap_read(struct file *file, char __user *buf,
         struct pagemapread pm;
         int pagecount;
         int ret = -ESRCH;
+        struct mm_walk pagemap_walk;
+        unsigned long src;
+        unsigned long svpfn;
+        unsigned long start_vaddr;
+        unsigned long end_vaddr;
 
         if (!task)
                 goto out;
 
         ret = -EACCES;
-        if (!ptrace_may_attach(task))
+        if (!ptrace_may_access(task, PTRACE_MODE_READ))
                 goto out_task;
 
         ret = -EINVAL;
         /* file position must be aligned */
-        if (*ppos % PM_ENTRY_BYTES)
+        if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES))
                 goto out_task;
 
         ret = 0;
@@ -642,11 +659,15 @@ static ssize_t pagemap_read(struct file *file, char __user *buf,
         if (!mm)
                 goto out_task;
 
-        ret = -ENOMEM;
+
         uaddr = (unsigned long)buf & PAGE_MASK;
         uend = (unsigned long)(buf + count);
         pagecount = (PAGE_ALIGN(uend) - uaddr) / PAGE_SIZE;
-        pages = kmalloc(pagecount * sizeof(struct page *), GFP_KERNEL);
+        ret = 0;
+        if (pagecount == 0)
+                goto out_mm;
+        pages = kcalloc(pagecount, sizeof(struct page *), GFP_KERNEL);
+        ret = -ENOMEM;
         if (!pages)
                 goto out_mm;
 
@@ -664,36 +685,36 @@ static ssize_t pagemap_read(struct file *file, char __user *buf,
                 goto out_pages;
         }
 
-        pm.out = buf;
-        pm.end = buf + count;
+        pm.out = (u64 *)buf;
+        pm.end = (u64 *)(buf + count);
 
-        if (!ptrace_may_attach(task)) {
-                ret = -EIO;
-        } else {
-                unsigned long src = *ppos;
-                unsigned long svpfn = src / PM_ENTRY_BYTES;
-                unsigned long start_vaddr = svpfn << PAGE_SHIFT;
-                unsigned long end_vaddr = TASK_SIZE_OF(task);
-
-                /* watch out for wraparound */
-                if (svpfn > TASK_SIZE_OF(task) >> PAGE_SHIFT)
-                        start_vaddr = end_vaddr;
-
-                /*
-                 * The odds are that this will stop walking way
-                 * before end_vaddr, because the length of the
-                 * user buffer is tracked in "pm", and the walk
-                 * will stop when we hit the end of the buffer.
-                 */
-                ret = walk_page_range(mm, start_vaddr, end_vaddr,
-                                        &pagemap_walk, &pm);
-                if (ret == PM_END_OF_BUFFER)
-                        ret = 0;
-                /* don't need mmap_sem for these, but this looks cleaner */
-                *ppos += pm.out - buf;
-                if (!ret)
-                        ret = pm.out - buf;
-        }
+        pagemap_walk.pmd_entry = pagemap_pte_range;
+        pagemap_walk.pte_hole = pagemap_pte_hole;
+        pagemap_walk.mm = mm;
+        pagemap_walk.private = &pm;
+
+        src = *ppos;
+        svpfn = src / PM_ENTRY_BYTES;
+        start_vaddr = svpfn << PAGE_SHIFT;
+        end_vaddr = TASK_SIZE_OF(task);
+
+        /* watch out for wraparound */
+        if (svpfn > TASK_SIZE_OF(task) >> PAGE_SHIFT)
+                start_vaddr = end_vaddr;
+
+        /*
+         * The odds are that this will stop walking way
+         * before end_vaddr, because the length of the
+         * user buffer is tracked in "pm", and the walk
+         * will stop when we hit the end of the buffer.
+         */
+        ret = walk_page_range(start_vaddr, end_vaddr, &pagemap_walk);
+        if (ret == PM_END_OF_BUFFER)
+                ret = 0;
+        /* don't need mmap_sem for these, but this looks cleaner */
+        *ppos += (char *)pm.out - buf;
+        if (!ret)
+                ret = (char *)pm.out - buf;
 
 out_pages:
         for (; pagecount; pagecount--) {
@@ -726,7 +747,7 @@ static int show_numa_map_checked(struct seq_file *m, void *v)
         struct proc_maps_private *priv = m->private;
         struct task_struct *task = priv->task;
 
-        if (maps_protect && !ptrace_may_attach(task))
+        if (maps_protect && !ptrace_may_access(task, PTRACE_MODE_READ))
                 return -EACCES;
 
         return show_numa_map(m, v);
diff --git a/fs/proc/task_nommu.c b/fs/proc/task_nommu.c
index 4b4f9cc2f186..5d84e7121df8 100644
--- a/fs/proc/task_nommu.c
+++ b/fs/proc/task_nommu.c
@@ -113,7 +113,7 @@ static int show_map(struct seq_file *m, void *_vml)
         struct proc_maps_private *priv = m->private;
         struct task_struct *task = priv->task;
 
-        if (maps_protect && !ptrace_may_attach(task))
+        if (maps_protect && !ptrace_may_access(task, PTRACE_MODE_READ))
                 return -EACCES;
 
         return nommu_vma_show(m, vml->vma);