v4.19.13 snapshot.
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
new file mode 100644
index 0000000..a027473
--- /dev/null
+++ b/fs/proc/task_mmu.c
@@ -0,0 +1,1830 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/mm.h>
+#include <linux/vmacache.h>
+#include <linux/hugetlb.h>
+#include <linux/huge_mm.h>
+#include <linux/mount.h>
+#include <linux/seq_file.h>
+#include <linux/highmem.h>
+#include <linux/ptrace.h>
+#include <linux/slab.h>
+#include <linux/pagemap.h>
+#include <linux/mempolicy.h>
+#include <linux/rmap.h>
+#include <linux/swap.h>
+#include <linux/sched/mm.h>
+#include <linux/swapops.h>
+#include <linux/mmu_notifier.h>
+#include <linux/page_idle.h>
+#include <linux/shmem_fs.h>
+#include <linux/uaccess.h>
+#include <linux/pkeys.h>
+
+#include <asm/elf.h>
+#include <asm/tlb.h>
+#include <asm/tlbflush.h>
+#include "internal.h"
+
+#define SEQ_PUT_DEC(str, val) \
+ seq_put_decimal_ull_width(m, str, (val) << (PAGE_SHIFT-10), 8)
+void task_mem(struct seq_file *m, struct mm_struct *mm)
+{
+ unsigned long text, lib, swap, anon, file, shmem;
+ unsigned long hiwater_vm, total_vm, hiwater_rss, total_rss;
+
+ anon = get_mm_counter(mm, MM_ANONPAGES);
+ file = get_mm_counter(mm, MM_FILEPAGES);
+ shmem = get_mm_counter(mm, MM_SHMEMPAGES);
+
+ /*
+ * Note: to minimize their overhead, mm maintains hiwater_vm and
+ * hiwater_rss only when about to *lower* total_vm or rss. Any
+ * collector of these hiwater stats must therefore get total_vm
+ * and rss too, which will usually be the higher. Barriers? not
+ * worth the effort, such snapshots can always be inconsistent.
+ */
+ hiwater_vm = total_vm = mm->total_vm;
+ if (hiwater_vm < mm->hiwater_vm)
+ hiwater_vm = mm->hiwater_vm;
+ hiwater_rss = total_rss = anon + file + shmem;
+ if (hiwater_rss < mm->hiwater_rss)
+ hiwater_rss = mm->hiwater_rss;
+
+ /* split executable areas between text and lib */
+ text = PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK);
+ text = min(text, mm->exec_vm << PAGE_SHIFT);
+ lib = (mm->exec_vm << PAGE_SHIFT) - text;
+
+ swap = get_mm_counter(mm, MM_SWAPENTS);
+ SEQ_PUT_DEC("VmPeak:\t", hiwater_vm);
+ SEQ_PUT_DEC(" kB\nVmSize:\t", total_vm);
+ SEQ_PUT_DEC(" kB\nVmLck:\t", mm->locked_vm);
+ SEQ_PUT_DEC(" kB\nVmPin:\t", mm->pinned_vm);
+ SEQ_PUT_DEC(" kB\nVmHWM:\t", hiwater_rss);
+ SEQ_PUT_DEC(" kB\nVmRSS:\t", total_rss);
+ SEQ_PUT_DEC(" kB\nRssAnon:\t", anon);
+ SEQ_PUT_DEC(" kB\nRssFile:\t", file);
+ SEQ_PUT_DEC(" kB\nRssShmem:\t", shmem);
+ SEQ_PUT_DEC(" kB\nVmData:\t", mm->data_vm);
+ SEQ_PUT_DEC(" kB\nVmStk:\t", mm->stack_vm);
+ seq_put_decimal_ull_width(m,
+ " kB\nVmExe:\t", text >> 10, 8);
+ seq_put_decimal_ull_width(m,
+ " kB\nVmLib:\t", lib >> 10, 8);
+ seq_put_decimal_ull_width(m,
+ " kB\nVmPTE:\t", mm_pgtables_bytes(mm) >> 10, 8);
+ SEQ_PUT_DEC(" kB\nVmSwap:\t", swap);
+ seq_puts(m, " kB\n");
+ hugetlb_report_usage(m, mm);
+}
+#undef SEQ_PUT_DEC
+
+unsigned long task_vsize(struct mm_struct *mm)
+{
+ return PAGE_SIZE * mm->total_vm;
+}
+
+unsigned long task_statm(struct mm_struct *mm,
+ unsigned long *shared, unsigned long *text,
+ unsigned long *data, unsigned long *resident)
+{
+ *shared = get_mm_counter(mm, MM_FILEPAGES) +
+ get_mm_counter(mm, MM_SHMEMPAGES);
+ *text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK))
+ >> PAGE_SHIFT;
+ *data = mm->data_vm + mm->stack_vm;
+ *resident = *shared + get_mm_counter(mm, MM_ANONPAGES);
+ return mm->total_vm;
+}
+
+#ifdef CONFIG_NUMA
+/*
+ * Save get_task_policy() for show_numa_map().
+ */
+static void hold_task_mempolicy(struct proc_maps_private *priv)
+{
+ struct task_struct *task = priv->task;
+
+ task_lock(task);
+ priv->task_mempolicy = get_task_policy(task);
+ mpol_get(priv->task_mempolicy);
+ task_unlock(task);
+}
+static void release_task_mempolicy(struct proc_maps_private *priv)
+{
+ mpol_put(priv->task_mempolicy);
+}
+#else
+static void hold_task_mempolicy(struct proc_maps_private *priv)
+{
+}
+static void release_task_mempolicy(struct proc_maps_private *priv)
+{
+}
+#endif
+
+static void vma_stop(struct proc_maps_private *priv)
+{
+ struct mm_struct *mm = priv->mm;
+
+ release_task_mempolicy(priv);
+ up_read(&mm->mmap_sem);
+ mmput(mm);
+}
+
+static struct vm_area_struct *
+m_next_vma(struct proc_maps_private *priv, struct vm_area_struct *vma)
+{
+ if (vma == priv->tail_vma)
+ return NULL;
+ return vma->vm_next ?: priv->tail_vma;
+}
+
+static void m_cache_vma(struct seq_file *m, struct vm_area_struct *vma)
+{
+ if (m->count < m->size) /* vma is copied successfully */
+ m->version = m_next_vma(m->private, vma) ? vma->vm_end : -1UL;
+}
+
+static void *m_start(struct seq_file *m, loff_t *ppos)
+{
+ struct proc_maps_private *priv = m->private;
+ unsigned long last_addr = m->version;
+ struct mm_struct *mm;
+ struct vm_area_struct *vma;
+ unsigned int pos = *ppos;
+
+ /* See m_cache_vma(). Zero at the start or after lseek. */
+ if (last_addr == -1UL)
+ return NULL;
+
+ priv->task = get_proc_task(priv->inode);
+ if (!priv->task)
+ return ERR_PTR(-ESRCH);
+
+ mm = priv->mm;
+ if (!mm || !mmget_not_zero(mm))
+ return NULL;
+
+ down_read(&mm->mmap_sem);
+ hold_task_mempolicy(priv);
+ priv->tail_vma = get_gate_vma(mm);
+
+ if (last_addr) {
+ vma = find_vma(mm, last_addr - 1);
+ if (vma && vma->vm_start <= last_addr)
+ vma = m_next_vma(priv, vma);
+ if (vma)
+ return vma;
+ }
+
+ m->version = 0;
+ if (pos < mm->map_count) {
+ for (vma = mm->mmap; pos; pos--) {
+ m->version = vma->vm_start;
+ vma = vma->vm_next;
+ }
+ return vma;
+ }
+
+ /* we do not bother to update m->version in this case */
+ if (pos == mm->map_count && priv->tail_vma)
+ return priv->tail_vma;
+
+ vma_stop(priv);
+ return NULL;
+}
+
+static void *m_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ struct proc_maps_private *priv = m->private;
+ struct vm_area_struct *next;
+
+ (*pos)++;
+ next = m_next_vma(priv, v);
+ if (!next)
+ vma_stop(priv);
+ return next;
+}
+
+static void m_stop(struct seq_file *m, void *v)
+{
+ struct proc_maps_private *priv = m->private;
+
+ if (!IS_ERR_OR_NULL(v))
+ vma_stop(priv);
+ if (priv->task) {
+ put_task_struct(priv->task);
+ priv->task = NULL;
+ }
+}
+
+static int proc_maps_open(struct inode *inode, struct file *file,
+ const struct seq_operations *ops, int psize)
+{
+ struct proc_maps_private *priv = __seq_open_private(file, ops, psize);
+
+ if (!priv)
+ return -ENOMEM;
+
+ priv->inode = inode;
+ priv->mm = proc_mem_open(inode, PTRACE_MODE_READ);
+ if (IS_ERR(priv->mm)) {
+ int err = PTR_ERR(priv->mm);
+
+ seq_release_private(inode, file);
+ return err;
+ }
+
+ return 0;
+}
+
+static int proc_map_release(struct inode *inode, struct file *file)
+{
+ struct seq_file *seq = file->private_data;
+ struct proc_maps_private *priv = seq->private;
+
+ if (priv->mm)
+ mmdrop(priv->mm);
+
+ return seq_release_private(inode, file);
+}
+
+static int do_maps_open(struct inode *inode, struct file *file,
+ const struct seq_operations *ops)
+{
+ return proc_maps_open(inode, file, ops,
+ sizeof(struct proc_maps_private));
+}
+
+/*
+ * Indicate if the VMA is a stack for the given task; for
+ * /proc/PID/maps that is the stack of the main task.
+ */
+static int is_stack(struct vm_area_struct *vma)
+{
+ /*
+ * We make no effort to guess what a given thread considers to be
+ * its "stack". It's not even well-defined for programs written
+ * languages like Go.
+ */
+ return vma->vm_start <= vma->vm_mm->start_stack &&
+ vma->vm_end >= vma->vm_mm->start_stack;
+}
+
+static void show_vma_header_prefix(struct seq_file *m,
+ unsigned long start, unsigned long end,
+ vm_flags_t flags, unsigned long long pgoff,
+ dev_t dev, unsigned long ino)
+{
+ seq_setwidth(m, 25 + sizeof(void *) * 6 - 1);
+ seq_put_hex_ll(m, NULL, start, 8);
+ seq_put_hex_ll(m, "-", end, 8);
+ seq_putc(m, ' ');
+ seq_putc(m, flags & VM_READ ? 'r' : '-');
+ seq_putc(m, flags & VM_WRITE ? 'w' : '-');
+ seq_putc(m, flags & VM_EXEC ? 'x' : '-');
+ seq_putc(m, flags & VM_MAYSHARE ? 's' : 'p');
+ seq_put_hex_ll(m, " ", pgoff, 8);
+ seq_put_hex_ll(m, " ", MAJOR(dev), 2);
+ seq_put_hex_ll(m, ":", MINOR(dev), 2);
+ seq_put_decimal_ull(m, " ", ino);
+ seq_putc(m, ' ');
+}
+
+static void
+show_map_vma(struct seq_file *m, struct vm_area_struct *vma)
+{
+ struct mm_struct *mm = vma->vm_mm;
+ struct file *file = vma->vm_file;
+ vm_flags_t flags = vma->vm_flags;
+ unsigned long ino = 0;
+ unsigned long long pgoff = 0;
+ unsigned long start, end;
+ dev_t dev = 0;
+ const char *name = NULL;
+
+ if (file) {
+ struct inode *inode = file_inode(vma->vm_file);
+ dev = inode->i_sb->s_dev;
+ ino = inode->i_ino;
+ pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT;
+ }
+
+ start = vma->vm_start;
+ end = vma->vm_end;
+ show_vma_header_prefix(m, start, end, flags, pgoff, dev, ino);
+
+ /*
+ * Print the dentry name for named mappings, and a
+ * special [heap] marker for the heap:
+ */
+ if (file) {
+ seq_pad(m, ' ');
+ seq_file_path(m, file, "\n");
+ goto done;
+ }
+
+ if (vma->vm_ops && vma->vm_ops->name) {
+ name = vma->vm_ops->name(vma);
+ if (name)
+ goto done;
+ }
+
+ name = arch_vma_name(vma);
+ if (!name) {
+ if (!mm) {
+ name = "[vdso]";
+ goto done;
+ }
+
+ if (vma->vm_start <= mm->brk &&
+ vma->vm_end >= mm->start_brk) {
+ name = "[heap]";
+ goto done;
+ }
+
+ if (is_stack(vma))
+ name = "[stack]";
+ }
+
+done:
+ if (name) {
+ seq_pad(m, ' ');
+ seq_puts(m, name);
+ }
+ seq_putc(m, '\n');
+}
+
+static int show_map(struct seq_file *m, void *v)
+{
+ show_map_vma(m, v);
+ m_cache_vma(m, v);
+ return 0;
+}
+
+static const struct seq_operations proc_pid_maps_op = {
+ .start = m_start,
+ .next = m_next,
+ .stop = m_stop,
+ .show = show_map
+};
+
+static int pid_maps_open(struct inode *inode, struct file *file)
+{
+ return do_maps_open(inode, file, &proc_pid_maps_op);
+}
+
+const struct file_operations proc_pid_maps_operations = {
+ .open = pid_maps_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = proc_map_release,
+};
+
+/*
+ * Proportional Set Size(PSS): my share of RSS.
+ *
+ * PSS of a process is the count of pages it has in memory, where each
+ * page is divided by the number of processes sharing it. So if a
+ * process has 1000 pages all to itself, and 1000 shared with one other
+ * process, its PSS will be 1500.
+ *
+ * To keep (accumulated) division errors low, we adopt a 64bit
+ * fixed-point pss counter to minimize division errors. So (pss >>
+ * PSS_SHIFT) would be the real byte count.
+ *
+ * A shift of 12 before division means (assuming 4K page size):
+ * - 1M 3-user-pages add up to 8KB errors;
+ * - supports mapcount up to 2^24, or 16M;
+ * - supports PSS up to 2^52 bytes, or 4PB.
+ */
+#define PSS_SHIFT 12
+
+#ifdef CONFIG_PROC_PAGE_MONITOR
+struct mem_size_stats {
+ unsigned long resident;
+ unsigned long shared_clean;
+ unsigned long shared_dirty;
+ unsigned long private_clean;
+ unsigned long private_dirty;
+ unsigned long referenced;
+ unsigned long anonymous;
+ unsigned long lazyfree;
+ unsigned long anonymous_thp;
+ unsigned long shmem_thp;
+ unsigned long swap;
+ unsigned long shared_hugetlb;
+ unsigned long private_hugetlb;
+ u64 pss;
+ u64 pss_locked;
+ u64 swap_pss;
+ bool check_shmem_swap;
+};
+
+static void smaps_account(struct mem_size_stats *mss, struct page *page,
+ bool compound, bool young, bool dirty)
+{
+ int i, nr = compound ? 1 << compound_order(page) : 1;
+ unsigned long size = nr * PAGE_SIZE;
+
+ if (PageAnon(page)) {
+ mss->anonymous += size;
+ if (!PageSwapBacked(page) && !dirty && !PageDirty(page))
+ mss->lazyfree += size;
+ }
+
+ mss->resident += size;
+ /* Accumulate the size in pages that have been accessed. */
+ if (young || page_is_young(page) || PageReferenced(page))
+ mss->referenced += size;
+
+ /*
+ * page_count(page) == 1 guarantees the page is mapped exactly once.
+ * If any subpage of the compound page mapped with PTE it would elevate
+ * page_count().
+ */
+ if (page_count(page) == 1) {
+ if (dirty || PageDirty(page))
+ mss->private_dirty += size;
+ else
+ mss->private_clean += size;
+ mss->pss += (u64)size << PSS_SHIFT;
+ return;
+ }
+
+ for (i = 0; i < nr; i++, page++) {
+ int mapcount = page_mapcount(page);
+
+ if (mapcount >= 2) {
+ if (dirty || PageDirty(page))
+ mss->shared_dirty += PAGE_SIZE;
+ else
+ mss->shared_clean += PAGE_SIZE;
+ mss->pss += (PAGE_SIZE << PSS_SHIFT) / mapcount;
+ } else {
+ if (dirty || PageDirty(page))
+ mss->private_dirty += PAGE_SIZE;
+ else
+ mss->private_clean += PAGE_SIZE;
+ mss->pss += PAGE_SIZE << PSS_SHIFT;
+ }
+ }
+}
+
+#ifdef CONFIG_SHMEM
+static int smaps_pte_hole(unsigned long addr, unsigned long end,
+ struct mm_walk *walk)
+{
+ struct mem_size_stats *mss = walk->private;
+
+ mss->swap += shmem_partial_swap_usage(
+ walk->vma->vm_file->f_mapping, addr, end);
+
+ return 0;
+}
+#endif
+
+static void smaps_pte_entry(pte_t *pte, unsigned long addr,
+ struct mm_walk *walk)
+{
+ struct mem_size_stats *mss = walk->private;
+ struct vm_area_struct *vma = walk->vma;
+ struct page *page = NULL;
+
+ if (pte_present(*pte)) {
+ page = vm_normal_page(vma, addr, *pte);
+ } else if (is_swap_pte(*pte)) {
+ swp_entry_t swpent = pte_to_swp_entry(*pte);
+
+ if (!non_swap_entry(swpent)) {
+ int mapcount;
+
+ mss->swap += PAGE_SIZE;
+ mapcount = swp_swapcount(swpent);
+ if (mapcount >= 2) {
+ u64 pss_delta = (u64)PAGE_SIZE << PSS_SHIFT;
+
+ do_div(pss_delta, mapcount);
+ mss->swap_pss += pss_delta;
+ } else {
+ mss->swap_pss += (u64)PAGE_SIZE << PSS_SHIFT;
+ }
+ } else if (is_migration_entry(swpent))
+ page = migration_entry_to_page(swpent);
+ else if (is_device_private_entry(swpent))
+ page = device_private_entry_to_page(swpent);
+ } else if (unlikely(IS_ENABLED(CONFIG_SHMEM) && mss->check_shmem_swap
+ && pte_none(*pte))) {
+ page = find_get_entry(vma->vm_file->f_mapping,
+ linear_page_index(vma, addr));
+ if (!page)
+ return;
+
+ if (radix_tree_exceptional_entry(page))
+ mss->swap += PAGE_SIZE;
+ else
+ put_page(page);
+
+ return;
+ }
+
+ if (!page)
+ return;
+
+ smaps_account(mss, page, false, pte_young(*pte), pte_dirty(*pte));
+}
+
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
+ struct mm_walk *walk)
+{
+ struct mem_size_stats *mss = walk->private;
+ struct vm_area_struct *vma = walk->vma;
+ struct page *page;
+
+ /* FOLL_DUMP will return -EFAULT on huge zero page */
+ page = follow_trans_huge_pmd(vma, addr, pmd, FOLL_DUMP);
+ if (IS_ERR_OR_NULL(page))
+ return;
+ if (PageAnon(page))
+ mss->anonymous_thp += HPAGE_PMD_SIZE;
+ else if (PageSwapBacked(page))
+ mss->shmem_thp += HPAGE_PMD_SIZE;
+ else if (is_zone_device_page(page))
+ /* pass */;
+ else
+ VM_BUG_ON_PAGE(1, page);
+ smaps_account(mss, page, true, pmd_young(*pmd), pmd_dirty(*pmd));
+}
+#else
+static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
+ struct mm_walk *walk)
+{
+}
+#endif
+
+static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
+ struct mm_walk *walk)
+{
+ struct vm_area_struct *vma = walk->vma;
+ pte_t *pte;
+ spinlock_t *ptl;
+
+ ptl = pmd_trans_huge_lock(pmd, vma);
+ if (ptl) {
+ if (pmd_present(*pmd))
+ smaps_pmd_entry(pmd, addr, walk);
+ spin_unlock(ptl);
+ goto out;
+ }
+
+ if (pmd_trans_unstable(pmd))
+ goto out;
+ /*
+ * The mmap_sem held all the way back in m_start() is what
+ * keeps khugepaged out of here and from collapsing things
+ * in here.
+ */
+ pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
+ for (; addr != end; pte++, addr += PAGE_SIZE)
+ smaps_pte_entry(pte, addr, walk);
+ pte_unmap_unlock(pte - 1, ptl);
+out:
+ cond_resched();
+ return 0;
+}
+
+static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma)
+{
+ /*
+ * Don't forget to update Documentation/ on changes.
+ */
+ static const char mnemonics[BITS_PER_LONG][2] = {
+ /*
+ * In case if we meet a flag we don't know about.
+ */
+ [0 ... (BITS_PER_LONG-1)] = "??",
+
+ [ilog2(VM_READ)] = "rd",
+ [ilog2(VM_WRITE)] = "wr",
+ [ilog2(VM_EXEC)] = "ex",
+ [ilog2(VM_SHARED)] = "sh",
+ [ilog2(VM_MAYREAD)] = "mr",
+ [ilog2(VM_MAYWRITE)] = "mw",
+ [ilog2(VM_MAYEXEC)] = "me",
+ [ilog2(VM_MAYSHARE)] = "ms",
+ [ilog2(VM_GROWSDOWN)] = "gd",
+ [ilog2(VM_PFNMAP)] = "pf",
+ [ilog2(VM_DENYWRITE)] = "dw",
+#ifdef CONFIG_X86_INTEL_MPX
+ [ilog2(VM_MPX)] = "mp",
+#endif
+ [ilog2(VM_LOCKED)] = "lo",
+ [ilog2(VM_IO)] = "io",
+ [ilog2(VM_SEQ_READ)] = "sr",
+ [ilog2(VM_RAND_READ)] = "rr",
+ [ilog2(VM_DONTCOPY)] = "dc",
+ [ilog2(VM_DONTEXPAND)] = "de",
+ [ilog2(VM_ACCOUNT)] = "ac",
+ [ilog2(VM_NORESERVE)] = "nr",
+ [ilog2(VM_HUGETLB)] = "ht",
+ [ilog2(VM_SYNC)] = "sf",
+ [ilog2(VM_ARCH_1)] = "ar",
+ [ilog2(VM_WIPEONFORK)] = "wf",
+ [ilog2(VM_DONTDUMP)] = "dd",
+#ifdef CONFIG_MEM_SOFT_DIRTY
+ [ilog2(VM_SOFTDIRTY)] = "sd",
+#endif
+ [ilog2(VM_MIXEDMAP)] = "mm",
+ [ilog2(VM_HUGEPAGE)] = "hg",
+ [ilog2(VM_NOHUGEPAGE)] = "nh",
+ [ilog2(VM_MERGEABLE)] = "mg",
+ [ilog2(VM_UFFD_MISSING)]= "um",
+ [ilog2(VM_UFFD_WP)] = "uw",
+#ifdef CONFIG_ARCH_HAS_PKEYS
+ /* These come out via ProtectionKey: */
+ [ilog2(VM_PKEY_BIT0)] = "",
+ [ilog2(VM_PKEY_BIT1)] = "",
+ [ilog2(VM_PKEY_BIT2)] = "",
+ [ilog2(VM_PKEY_BIT3)] = "",
+#if VM_PKEY_BIT4
+ [ilog2(VM_PKEY_BIT4)] = "",
+#endif
+#endif /* CONFIG_ARCH_HAS_PKEYS */
+ };
+ size_t i;
+
+ seq_puts(m, "VmFlags: ");
+ for (i = 0; i < BITS_PER_LONG; i++) {
+ if (!mnemonics[i][0])
+ continue;
+ if (vma->vm_flags & (1UL << i)) {
+ seq_putc(m, mnemonics[i][0]);
+ seq_putc(m, mnemonics[i][1]);
+ seq_putc(m, ' ');
+ }
+ }
+ seq_putc(m, '\n');
+}
+
+#ifdef CONFIG_HUGETLB_PAGE
+static int smaps_hugetlb_range(pte_t *pte, unsigned long hmask,
+ unsigned long addr, unsigned long end,
+ struct mm_walk *walk)
+{
+ struct mem_size_stats *mss = walk->private;
+ struct vm_area_struct *vma = walk->vma;
+ struct page *page = NULL;
+
+ if (pte_present(*pte)) {
+ page = vm_normal_page(vma, addr, *pte);
+ } else if (is_swap_pte(*pte)) {
+ swp_entry_t swpent = pte_to_swp_entry(*pte);
+
+ if (is_migration_entry(swpent))
+ page = migration_entry_to_page(swpent);
+ else if (is_device_private_entry(swpent))
+ page = device_private_entry_to_page(swpent);
+ }
+ if (page) {
+ int mapcount = page_mapcount(page);
+
+ if (mapcount >= 2)
+ mss->shared_hugetlb += huge_page_size(hstate_vma(vma));
+ else
+ mss->private_hugetlb += huge_page_size(hstate_vma(vma));
+ }
+ return 0;
+}
+#endif /* HUGETLB_PAGE */
+
+static void smap_gather_stats(struct vm_area_struct *vma,
+ struct mem_size_stats *mss)
+{
+ struct mm_walk smaps_walk = {
+ .pmd_entry = smaps_pte_range,
+#ifdef CONFIG_HUGETLB_PAGE
+ .hugetlb_entry = smaps_hugetlb_range,
+#endif
+ .mm = vma->vm_mm,
+ };
+
+ smaps_walk.private = mss;
+
+#ifdef CONFIG_SHMEM
+ /* In case of smaps_rollup, reset the value from previous vma */
+ mss->check_shmem_swap = false;
+ if (vma->vm_file && shmem_mapping(vma->vm_file->f_mapping)) {
+ /*
+ * For shared or readonly shmem mappings we know that all
+ * swapped out pages belong to the shmem object, and we can
+ * obtain the swap value much more efficiently. For private
+ * writable mappings, we might have COW pages that are
+ * not affected by the parent swapped out pages of the shmem
+ * object, so we have to distinguish them during the page walk.
+ * Unless we know that the shmem object (or the part mapped by
+ * our VMA) has no swapped out pages at all.
+ */
+ unsigned long shmem_swapped = shmem_swap_usage(vma);
+
+ if (!shmem_swapped || (vma->vm_flags & VM_SHARED) ||
+ !(vma->vm_flags & VM_WRITE)) {
+ mss->swap += shmem_swapped;
+ } else {
+ mss->check_shmem_swap = true;
+ smaps_walk.pte_hole = smaps_pte_hole;
+ }
+ }
+#endif
+
+ /* mmap_sem is held in m_start */
+ walk_page_vma(vma, &smaps_walk);
+ if (vma->vm_flags & VM_LOCKED)
+ mss->pss_locked += mss->pss;
+}
+
+#define SEQ_PUT_DEC(str, val) \
+ seq_put_decimal_ull_width(m, str, (val) >> 10, 8)
+
+/* Show the contents common for smaps and smaps_rollup */
+static void __show_smap(struct seq_file *m, const struct mem_size_stats *mss)
+{
+ SEQ_PUT_DEC("Rss: ", mss->resident);
+ SEQ_PUT_DEC(" kB\nPss: ", mss->pss >> PSS_SHIFT);
+ SEQ_PUT_DEC(" kB\nShared_Clean: ", mss->shared_clean);
+ SEQ_PUT_DEC(" kB\nShared_Dirty: ", mss->shared_dirty);
+ SEQ_PUT_DEC(" kB\nPrivate_Clean: ", mss->private_clean);
+ SEQ_PUT_DEC(" kB\nPrivate_Dirty: ", mss->private_dirty);
+ SEQ_PUT_DEC(" kB\nReferenced: ", mss->referenced);
+ SEQ_PUT_DEC(" kB\nAnonymous: ", mss->anonymous);
+ SEQ_PUT_DEC(" kB\nLazyFree: ", mss->lazyfree);
+ SEQ_PUT_DEC(" kB\nAnonHugePages: ", mss->anonymous_thp);
+ SEQ_PUT_DEC(" kB\nShmemPmdMapped: ", mss->shmem_thp);
+ SEQ_PUT_DEC(" kB\nShared_Hugetlb: ", mss->shared_hugetlb);
+ seq_put_decimal_ull_width(m, " kB\nPrivate_Hugetlb: ",
+ mss->private_hugetlb >> 10, 7);
+ SEQ_PUT_DEC(" kB\nSwap: ", mss->swap);
+ SEQ_PUT_DEC(" kB\nSwapPss: ",
+ mss->swap_pss >> PSS_SHIFT);
+ SEQ_PUT_DEC(" kB\nLocked: ",
+ mss->pss_locked >> PSS_SHIFT);
+ seq_puts(m, " kB\n");
+}
+
+static int show_smap(struct seq_file *m, void *v)
+{
+ struct vm_area_struct *vma = v;
+ struct mem_size_stats mss;
+
+ memset(&mss, 0, sizeof(mss));
+
+ smap_gather_stats(vma, &mss);
+
+ show_map_vma(m, vma);
+
+ SEQ_PUT_DEC("Size: ", vma->vm_end - vma->vm_start);
+ SEQ_PUT_DEC(" kB\nKernelPageSize: ", vma_kernel_pagesize(vma));
+ SEQ_PUT_DEC(" kB\nMMUPageSize: ", vma_mmu_pagesize(vma));
+ seq_puts(m, " kB\n");
+
+ __show_smap(m, &mss);
+
+ if (arch_pkeys_enabled())
+ seq_printf(m, "ProtectionKey: %8u\n", vma_pkey(vma));
+ show_smap_vma_flags(m, vma);
+
+ m_cache_vma(m, vma);
+
+ return 0;
+}
+
+static int show_smaps_rollup(struct seq_file *m, void *v)
+{
+ struct proc_maps_private *priv = m->private;
+ struct mem_size_stats mss;
+ struct mm_struct *mm;
+ struct vm_area_struct *vma;
+ unsigned long last_vma_end = 0;
+ int ret = 0;
+
+ priv->task = get_proc_task(priv->inode);
+ if (!priv->task)
+ return -ESRCH;
+
+ mm = priv->mm;
+ if (!mm || !mmget_not_zero(mm)) {
+ ret = -ESRCH;
+ goto out_put_task;
+ }
+
+ memset(&mss, 0, sizeof(mss));
+
+ down_read(&mm->mmap_sem);
+ hold_task_mempolicy(priv);
+
+ for (vma = priv->mm->mmap; vma; vma = vma->vm_next) {
+ smap_gather_stats(vma, &mss);
+ last_vma_end = vma->vm_end;
+ }
+
+ show_vma_header_prefix(m, priv->mm->mmap->vm_start,
+ last_vma_end, 0, 0, 0, 0);
+ seq_pad(m, ' ');
+ seq_puts(m, "[rollup]\n");
+
+ __show_smap(m, &mss);
+
+ release_task_mempolicy(priv);
+ up_read(&mm->mmap_sem);
+ mmput(mm);
+
+out_put_task:
+ put_task_struct(priv->task);
+ priv->task = NULL;
+
+ return ret;
+}
+#undef SEQ_PUT_DEC
+
+static const struct seq_operations proc_pid_smaps_op = {
+ .start = m_start,
+ .next = m_next,
+ .stop = m_stop,
+ .show = show_smap
+};
+
+static int pid_smaps_open(struct inode *inode, struct file *file)
+{
+ return do_maps_open(inode, file, &proc_pid_smaps_op);
+}
+
+static int smaps_rollup_open(struct inode *inode, struct file *file)
+{
+ int ret;
+ struct proc_maps_private *priv;
+
+ priv = kzalloc(sizeof(*priv), GFP_KERNEL_ACCOUNT);
+ if (!priv)
+ return -ENOMEM;
+
+ ret = single_open(file, show_smaps_rollup, priv);
+ if (ret)
+ goto out_free;
+
+ priv->inode = inode;
+ priv->mm = proc_mem_open(inode, PTRACE_MODE_READ);
+ if (IS_ERR(priv->mm)) {
+ ret = PTR_ERR(priv->mm);
+
+ single_release(inode, file);
+ goto out_free;
+ }
+
+ return 0;
+
+out_free:
+ kfree(priv);
+ return ret;
+}
+
+static int smaps_rollup_release(struct inode *inode, struct file *file)
+{
+ struct seq_file *seq = file->private_data;
+ struct proc_maps_private *priv = seq->private;
+
+ if (priv->mm)
+ mmdrop(priv->mm);
+
+ kfree(priv);
+ return single_release(inode, file);
+}
+
+const struct file_operations proc_pid_smaps_operations = {
+ .open = pid_smaps_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = proc_map_release,
+};
+
+const struct file_operations proc_pid_smaps_rollup_operations = {
+ .open = smaps_rollup_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = smaps_rollup_release,
+};
+
+enum clear_refs_types {
+ CLEAR_REFS_ALL = 1,
+ CLEAR_REFS_ANON,
+ CLEAR_REFS_MAPPED,
+ CLEAR_REFS_SOFT_DIRTY,
+ CLEAR_REFS_MM_HIWATER_RSS,
+ CLEAR_REFS_LAST,
+};
+
+struct clear_refs_private {
+ enum clear_refs_types type;
+};
+
+#ifdef CONFIG_MEM_SOFT_DIRTY
+static inline void clear_soft_dirty(struct vm_area_struct *vma,
+ unsigned long addr, pte_t *pte)
+{
+ /*
+ * The soft-dirty tracker uses #PF-s to catch writes
+ * to pages, so write-protect the pte as well. See the
+ * Documentation/admin-guide/mm/soft-dirty.rst for full description
+ * of how soft-dirty works.
+ */
+ pte_t ptent = *pte;
+
+ if (pte_present(ptent)) {
+ ptent = ptep_modify_prot_start(vma->vm_mm, addr, pte);
+ ptent = pte_wrprotect(ptent);
+ ptent = pte_clear_soft_dirty(ptent);
+ ptep_modify_prot_commit(vma->vm_mm, addr, pte, ptent);
+ } else if (is_swap_pte(ptent)) {
+ ptent = pte_swp_clear_soft_dirty(ptent);
+ set_pte_at(vma->vm_mm, addr, pte, ptent);
+ }
+}
+#else
+static inline void clear_soft_dirty(struct vm_area_struct *vma,
+ unsigned long addr, pte_t *pte)
+{
+}
+#endif
+
+#if defined(CONFIG_MEM_SOFT_DIRTY) && defined(CONFIG_TRANSPARENT_HUGEPAGE)
+static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
+ unsigned long addr, pmd_t *pmdp)
+{
+ pmd_t old, pmd = *pmdp;
+
+ if (pmd_present(pmd)) {
+ /* See comment in change_huge_pmd() */
+ old = pmdp_invalidate(vma, addr, pmdp);
+ if (pmd_dirty(old))
+ pmd = pmd_mkdirty(pmd);
+ if (pmd_young(old))
+ pmd = pmd_mkyoung(pmd);
+
+ pmd = pmd_wrprotect(pmd);
+ pmd = pmd_clear_soft_dirty(pmd);
+
+ set_pmd_at(vma->vm_mm, addr, pmdp, pmd);
+ } else if (is_migration_entry(pmd_to_swp_entry(pmd))) {
+ pmd = pmd_swp_clear_soft_dirty(pmd);
+ set_pmd_at(vma->vm_mm, addr, pmdp, pmd);
+ }
+}
+#else
+static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
+ unsigned long addr, pmd_t *pmdp)
+{
+}
+#endif
+
+static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr,
+ unsigned long end, struct mm_walk *walk)
+{
+ struct clear_refs_private *cp = walk->private;
+ struct vm_area_struct *vma = walk->vma;
+ pte_t *pte, ptent;
+ spinlock_t *ptl;
+ struct page *page;
+
+ ptl = pmd_trans_huge_lock(pmd, vma);
+ if (ptl) {
+ if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
+ clear_soft_dirty_pmd(vma, addr, pmd);
+ goto out;
+ }
+
+ if (!pmd_present(*pmd))
+ goto out;
+
+ page = pmd_page(*pmd);
+
+ /* Clear accessed and referenced bits. */
+ pmdp_test_and_clear_young(vma, addr, pmd);
+ test_and_clear_page_young(page);
+ ClearPageReferenced(page);
+out:
+ spin_unlock(ptl);
+ return 0;
+ }
+
+ if (pmd_trans_unstable(pmd))
+ return 0;
+
+ pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
+ for (; addr != end; pte++, addr += PAGE_SIZE) {
+ ptent = *pte;
+
+ if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
+ clear_soft_dirty(vma, addr, pte);
+ continue;
+ }
+
+ if (!pte_present(ptent))
+ continue;
+
+ page = vm_normal_page(vma, addr, ptent);
+ if (!page)
+ continue;
+
+ /* Clear accessed and referenced bits. */
+ ptep_test_and_clear_young(vma, addr, pte);
+ test_and_clear_page_young(page);
+ ClearPageReferenced(page);
+ }
+ pte_unmap_unlock(pte - 1, ptl);
+ cond_resched();
+ return 0;
+}
+
+static int clear_refs_test_walk(unsigned long start, unsigned long end,
+ struct mm_walk *walk)
+{
+ struct clear_refs_private *cp = walk->private;
+ struct vm_area_struct *vma = walk->vma;
+
+ if (vma->vm_flags & VM_PFNMAP)
+ return 1;
+
+ /*
+ * Writing 1 to /proc/pid/clear_refs affects all pages.
+ * Writing 2 to /proc/pid/clear_refs only affects anonymous pages.
+ * Writing 3 to /proc/pid/clear_refs only affects file mapped pages.
+ * Writing 4 to /proc/pid/clear_refs affects all pages.
+ */
+ if (cp->type == CLEAR_REFS_ANON && vma->vm_file)
+ return 1;
+ if (cp->type == CLEAR_REFS_MAPPED && !vma->vm_file)
+ return 1;
+ return 0;
+}
+
+static ssize_t clear_refs_write(struct file *file, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ struct task_struct *task;
+ char buffer[PROC_NUMBUF];
+ struct mm_struct *mm;
+ struct vm_area_struct *vma;
+ enum clear_refs_types type;
+ struct mmu_gather tlb;
+ int itype;
+ int rv;
+
+ memset(buffer, 0, sizeof(buffer));
+ if (count > sizeof(buffer) - 1)
+ count = sizeof(buffer) - 1;
+ if (copy_from_user(buffer, buf, count))
+ return -EFAULT;
+ rv = kstrtoint(strstrip(buffer), 10, &itype);
+ if (rv < 0)
+ return rv;
+ type = (enum clear_refs_types)itype;
+ if (type < CLEAR_REFS_ALL || type >= CLEAR_REFS_LAST)
+ return -EINVAL;
+
+ task = get_proc_task(file_inode(file));
+ if (!task)
+ return -ESRCH;
+ mm = get_task_mm(task);
+ if (mm) {
+ struct clear_refs_private cp = {
+ .type = type,
+ };
+ struct mm_walk clear_refs_walk = {
+ .pmd_entry = clear_refs_pte_range,
+ .test_walk = clear_refs_test_walk,
+ .mm = mm,
+ .private = &cp,
+ };
+
+ if (type == CLEAR_REFS_MM_HIWATER_RSS) {
+ if (down_write_killable(&mm->mmap_sem)) {
+ count = -EINTR;
+ goto out_mm;
+ }
+
+ /*
+ * Writing 5 to /proc/pid/clear_refs resets the peak
+ * resident set size to this mm's current rss value.
+ */
+ reset_mm_hiwater_rss(mm);
+ up_write(&mm->mmap_sem);
+ goto out_mm;
+ }
+
+ down_read(&mm->mmap_sem);
+ tlb_gather_mmu(&tlb, mm, 0, -1);
+ if (type == CLEAR_REFS_SOFT_DIRTY) {
+ for (vma = mm->mmap; vma; vma = vma->vm_next) {
+ if (!(vma->vm_flags & VM_SOFTDIRTY))
+ continue;
+ up_read(&mm->mmap_sem);
+ if (down_write_killable(&mm->mmap_sem)) {
+ count = -EINTR;
+ goto out_mm;
+ }
+ for (vma = mm->mmap; vma; vma = vma->vm_next) {
+ vma->vm_flags &= ~VM_SOFTDIRTY;
+ vma_set_page_prot(vma);
+ }
+ downgrade_write(&mm->mmap_sem);
+ break;
+ }
+ mmu_notifier_invalidate_range_start(mm, 0, -1);
+ }
+ walk_page_range(0, mm->highest_vm_end, &clear_refs_walk);
+ if (type == CLEAR_REFS_SOFT_DIRTY)
+ mmu_notifier_invalidate_range_end(mm, 0, -1);
+ tlb_finish_mmu(&tlb, 0, -1);
+ up_read(&mm->mmap_sem);
+out_mm:
+ mmput(mm);
+ }
+ put_task_struct(task);
+
+ return count;
+}
+
+const struct file_operations proc_clear_refs_operations = {
+ .write = clear_refs_write,
+ .llseek = noop_llseek,
+};
+
+typedef struct {
+ u64 pme;
+} pagemap_entry_t;
+
+struct pagemapread {
+ int pos, len; /* units: PM_ENTRY_BYTES, not bytes */
+ pagemap_entry_t *buffer;
+ bool show_pfn;
+};
+
+#define PAGEMAP_WALK_SIZE (PMD_SIZE)
+#define PAGEMAP_WALK_MASK (PMD_MASK)
+
+#define PM_ENTRY_BYTES sizeof(pagemap_entry_t)
+#define PM_PFRAME_BITS 55
+#define PM_PFRAME_MASK GENMASK_ULL(PM_PFRAME_BITS - 1, 0)
+#define PM_SOFT_DIRTY BIT_ULL(55)
+#define PM_MMAP_EXCLUSIVE BIT_ULL(56)
+#define PM_FILE BIT_ULL(61)
+#define PM_SWAP BIT_ULL(62)
+#define PM_PRESENT BIT_ULL(63)
+
+#define PM_END_OF_BUFFER 1
+
+static inline pagemap_entry_t make_pme(u64 frame, u64 flags)
+{
+ return (pagemap_entry_t) { .pme = (frame & PM_PFRAME_MASK) | flags };
+}
+
+static int add_to_pagemap(unsigned long addr, pagemap_entry_t *pme,
+ struct pagemapread *pm)
+{
+ pm->buffer[pm->pos++] = *pme;
+ if (pm->pos >= pm->len)
+ return PM_END_OF_BUFFER;
+ return 0;
+}
+
+static int pagemap_pte_hole(unsigned long start, unsigned long end,
+ struct mm_walk *walk)
+{
+ struct pagemapread *pm = walk->private;
+ unsigned long addr = start;
+ int err = 0;
+
+ while (addr < end) {
+ struct vm_area_struct *vma = find_vma(walk->mm, addr);
+ pagemap_entry_t pme = make_pme(0, 0);
+ /* End of address space hole, which we mark as non-present. */
+ unsigned long hole_end;
+
+ if (vma)
+ hole_end = min(end, vma->vm_start);
+ else
+ hole_end = end;
+
+ for (; addr < hole_end; addr += PAGE_SIZE) {
+ err = add_to_pagemap(addr, &pme, pm);
+ if (err)
+ goto out;
+ }
+
+ if (!vma)
+ break;
+
+ /* Addresses in the VMA. */
+ if (vma->vm_flags & VM_SOFTDIRTY)
+ pme = make_pme(0, PM_SOFT_DIRTY);
+ for (; addr < min(end, vma->vm_end); addr += PAGE_SIZE) {
+ err = add_to_pagemap(addr, &pme, pm);
+ if (err)
+ goto out;
+ }
+ }
+out:
+ return err;
+}
+
+static pagemap_entry_t pte_to_pagemap_entry(struct pagemapread *pm,
+ struct vm_area_struct *vma, unsigned long addr, pte_t pte)
+{
+ u64 frame = 0, flags = 0;
+ struct page *page = NULL;
+
+ if (pte_present(pte)) {
+ if (pm->show_pfn)
+ frame = pte_pfn(pte);
+ flags |= PM_PRESENT;
+ page = _vm_normal_page(vma, addr, pte, true);
+ if (pte_soft_dirty(pte))
+ flags |= PM_SOFT_DIRTY;
+ } else if (is_swap_pte(pte)) {
+ swp_entry_t entry;
+ if (pte_swp_soft_dirty(pte))
+ flags |= PM_SOFT_DIRTY;
+ entry = pte_to_swp_entry(pte);
+ if (pm->show_pfn)
+ frame = swp_type(entry) |
+ (swp_offset(entry) << MAX_SWAPFILES_SHIFT);
+ flags |= PM_SWAP;
+ if (is_migration_entry(entry))
+ page = migration_entry_to_page(entry);
+
+ if (is_device_private_entry(entry))
+ page = device_private_entry_to_page(entry);
+ }
+
+ if (page && !PageAnon(page))
+ flags |= PM_FILE;
+ if (page && page_mapcount(page) == 1)
+ flags |= PM_MMAP_EXCLUSIVE;
+ if (vma->vm_flags & VM_SOFTDIRTY)
+ flags |= PM_SOFT_DIRTY;
+
+ return make_pme(frame, flags);
+}
+
+static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end,
+ struct mm_walk *walk)
+{
+ struct vm_area_struct *vma = walk->vma;
+ struct pagemapread *pm = walk->private;
+ spinlock_t *ptl;
+ pte_t *pte, *orig_pte;
+ int err = 0;
+
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+ ptl = pmd_trans_huge_lock(pmdp, vma);
+ if (ptl) {
+ u64 flags = 0, frame = 0;
+ pmd_t pmd = *pmdp;
+ struct page *page = NULL;
+
+ if (vma->vm_flags & VM_SOFTDIRTY)
+ flags |= PM_SOFT_DIRTY;
+
+ if (pmd_present(pmd)) {
+ page = pmd_page(pmd);
+
+ flags |= PM_PRESENT;
+ if (pmd_soft_dirty(pmd))
+ flags |= PM_SOFT_DIRTY;
+ if (pm->show_pfn)
+ frame = pmd_pfn(pmd) +
+ ((addr & ~PMD_MASK) >> PAGE_SHIFT);
+ }
+#ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION
+ else if (is_swap_pmd(pmd)) {
+ swp_entry_t entry = pmd_to_swp_entry(pmd);
+ unsigned long offset;
+
+ if (pm->show_pfn) {
+ offset = swp_offset(entry) +
+ ((addr & ~PMD_MASK) >> PAGE_SHIFT);
+ frame = swp_type(entry) |
+ (offset << MAX_SWAPFILES_SHIFT);
+ }
+ flags |= PM_SWAP;
+ if (pmd_swp_soft_dirty(pmd))
+ flags |= PM_SOFT_DIRTY;
+ VM_BUG_ON(!is_pmd_migration_entry(pmd));
+ page = migration_entry_to_page(entry);
+ }
+#endif
+
+ if (page && page_mapcount(page) == 1)
+ flags |= PM_MMAP_EXCLUSIVE;
+
+ for (; addr != end; addr += PAGE_SIZE) {
+ pagemap_entry_t pme = make_pme(frame, flags);
+
+ err = add_to_pagemap(addr, &pme, pm);
+ if (err)
+ break;
+ if (pm->show_pfn) {
+ if (flags & PM_PRESENT)
+ frame++;
+ else if (flags & PM_SWAP)
+ frame += (1 << MAX_SWAPFILES_SHIFT);
+ }
+ }
+ spin_unlock(ptl);
+ return err;
+ }
+
+ if (pmd_trans_unstable(pmdp))
+ return 0;
+#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
+
+ /*
+ * We can assume that @vma always points to a valid one and @end never
+ * goes beyond vma->vm_end.
+ */
+ orig_pte = pte = pte_offset_map_lock(walk->mm, pmdp, addr, &ptl);
+ for (; addr < end; pte++, addr += PAGE_SIZE) {
+ pagemap_entry_t pme;
+
+ pme = pte_to_pagemap_entry(pm, vma, addr, *pte);
+ err = add_to_pagemap(addr, &pme, pm);
+ if (err)
+ break;
+ }
+ pte_unmap_unlock(orig_pte, ptl);
+
+ cond_resched();
+
+ return err;
+}
+
+#ifdef CONFIG_HUGETLB_PAGE
+/* This function walks within one hugetlb entry in the single call */
+static int pagemap_hugetlb_range(pte_t *ptep, unsigned long hmask,
+ unsigned long addr, unsigned long end,
+ struct mm_walk *walk)
+{
+ struct pagemapread *pm = walk->private;
+ struct vm_area_struct *vma = walk->vma;
+ u64 flags = 0, frame = 0;
+ int err = 0;
+ pte_t pte;
+
+ if (vma->vm_flags & VM_SOFTDIRTY)
+ flags |= PM_SOFT_DIRTY;
+
+ pte = huge_ptep_get(ptep);
+ if (pte_present(pte)) {
+ struct page *page = pte_page(pte);
+
+ if (!PageAnon(page))
+ flags |= PM_FILE;
+
+ if (page_mapcount(page) == 1)
+ flags |= PM_MMAP_EXCLUSIVE;
+
+ flags |= PM_PRESENT;
+ if (pm->show_pfn)
+ frame = pte_pfn(pte) +
+ ((addr & ~hmask) >> PAGE_SHIFT);
+ }
+
+ for (; addr != end; addr += PAGE_SIZE) {
+ pagemap_entry_t pme = make_pme(frame, flags);
+
+ err = add_to_pagemap(addr, &pme, pm);
+ if (err)
+ return err;
+ if (pm->show_pfn && (flags & PM_PRESENT))
+ frame++;
+ }
+
+ cond_resched();
+
+ return err;
+}
+#endif /* HUGETLB_PAGE */
+
+/*
+ * /proc/pid/pagemap - an array mapping virtual pages to pfns
+ *
+ * For each page in the address space, this file contains one 64-bit entry
+ * consisting of the following:
+ *
+ * Bits 0-54 page frame number (PFN) if present
+ * Bits 0-4 swap type if swapped
+ * Bits 5-54 swap offset if swapped
+ * Bit 55 pte is soft-dirty (see Documentation/admin-guide/mm/soft-dirty.rst)
+ * Bit 56 page exclusively mapped
+ * Bits 57-60 zero
+ * Bit 61 page is file-page or shared-anon
+ * Bit 62 page swapped
+ * Bit 63 page present
+ *
+ * If the page is not present but in swap, then the PFN contains an
+ * encoding of the swap file number and the page's offset into the
+ * swap. Unmapped pages return a null PFN. This allows determining
+ * precisely which pages are mapped (or in swap) and comparing mapped
+ * pages between processes.
+ *
+ * Efficient users of this interface will use /proc/pid/maps to
+ * determine which areas of memory are actually mapped and llseek to
+ * skip over unmapped regions.
+ */
+static ssize_t pagemap_read(struct file *file, char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ struct mm_struct *mm = file->private_data;
+ struct pagemapread pm;
+ struct mm_walk pagemap_walk = {};
+ unsigned long src;
+ unsigned long svpfn;
+ unsigned long start_vaddr;
+ unsigned long end_vaddr;
+ int ret = 0, copied = 0;
+
+ if (!mm || !mmget_not_zero(mm))
+ goto out;
+
+ ret = -EINVAL;
+ /* file position must be aligned */
+ if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES))
+ goto out_mm;
+
+ ret = 0;
+ if (!count)
+ goto out_mm;
+
+ /* do not disclose physical addresses: attack vector */
+ pm.show_pfn = file_ns_capable(file, &init_user_ns, CAP_SYS_ADMIN);
+
+ pm.len = (PAGEMAP_WALK_SIZE >> PAGE_SHIFT);
+ pm.buffer = kmalloc_array(pm.len, PM_ENTRY_BYTES, GFP_KERNEL);
+ ret = -ENOMEM;
+ if (!pm.buffer)
+ goto out_mm;
+
+ pagemap_walk.pmd_entry = pagemap_pmd_range;
+ pagemap_walk.pte_hole = pagemap_pte_hole;
+#ifdef CONFIG_HUGETLB_PAGE
+ pagemap_walk.hugetlb_entry = pagemap_hugetlb_range;
+#endif
+ pagemap_walk.mm = mm;
+ pagemap_walk.private = ±
+
+ src = *ppos;
+ svpfn = src / PM_ENTRY_BYTES;
+ start_vaddr = svpfn << PAGE_SHIFT;
+ end_vaddr = mm->task_size;
+
+ /* watch out for wraparound */
+ if (svpfn > mm->task_size >> 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 = 0;
+ while (count && (start_vaddr < end_vaddr)) {
+ int len;
+ unsigned long end;
+
+ pm.pos = 0;
+ end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK;
+ /* overflow ? */
+ if (end < start_vaddr || end > end_vaddr)
+ end = end_vaddr;
+ down_read(&mm->mmap_sem);
+ ret = walk_page_range(start_vaddr, end, &pagemap_walk);
+ up_read(&mm->mmap_sem);
+ start_vaddr = end;
+
+ len = min(count, PM_ENTRY_BYTES * pm.pos);
+ if (copy_to_user(buf, pm.buffer, len)) {
+ ret = -EFAULT;
+ goto out_free;
+ }
+ copied += len;
+ buf += len;
+ count -= len;
+ }
+ *ppos += copied;
+ if (!ret || ret == PM_END_OF_BUFFER)
+ ret = copied;
+
+out_free:
+ kfree(pm.buffer);
+out_mm:
+ mmput(mm);
+out:
+ return ret;
+}
+
+static int pagemap_open(struct inode *inode, struct file *file)
+{
+ struct mm_struct *mm;
+
+ mm = proc_mem_open(inode, PTRACE_MODE_READ);
+ if (IS_ERR(mm))
+ return PTR_ERR(mm);
+ file->private_data = mm;
+ return 0;
+}
+
+static int pagemap_release(struct inode *inode, struct file *file)
+{
+ struct mm_struct *mm = file->private_data;
+
+ if (mm)
+ mmdrop(mm);
+ return 0;
+}
+
+const struct file_operations proc_pagemap_operations = {
+ .llseek = mem_lseek, /* borrow this */
+ .read = pagemap_read,
+ .open = pagemap_open,
+ .release = pagemap_release,
+};
+#endif /* CONFIG_PROC_PAGE_MONITOR */
+
+#ifdef CONFIG_NUMA
+
+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];
+};
+
+struct numa_maps_private {
+ struct proc_maps_private proc_maps;
+ struct numa_maps md;
+};
+
+static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty,
+ unsigned long nr_pages)
+{
+ int count = page_mapcount(page);
+
+ md->pages += nr_pages;
+ if (pte_dirty || PageDirty(page))
+ md->dirty += nr_pages;
+
+ if (PageSwapCache(page))
+ md->swapcache += nr_pages;
+
+ if (PageActive(page) || PageUnevictable(page))
+ md->active += nr_pages;
+
+ if (PageWriteback(page))
+ md->writeback += nr_pages;
+
+ if (PageAnon(page))
+ md->anon += nr_pages;
+
+ if (count > md->mapcount_max)
+ md->mapcount_max = count;
+
+ md->node[page_to_nid(page)] += nr_pages;
+}
+
+static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma,
+ unsigned long addr)
+{
+ struct page *page;
+ int nid;
+
+ if (!pte_present(pte))
+ return NULL;
+
+ page = vm_normal_page(vma, addr, pte);
+ if (!page)
+ return NULL;
+
+ if (PageReserved(page))
+ return NULL;
+
+ nid = page_to_nid(page);
+ if (!node_isset(nid, node_states[N_MEMORY]))
+ return NULL;
+
+ return page;
+}
+
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+static struct page *can_gather_numa_stats_pmd(pmd_t pmd,
+ struct vm_area_struct *vma,
+ unsigned long addr)
+{
+ struct page *page;
+ int nid;
+
+ if (!pmd_present(pmd))
+ return NULL;
+
+ page = vm_normal_page_pmd(vma, addr, pmd);
+ if (!page)
+ return NULL;
+
+ if (PageReserved(page))
+ return NULL;
+
+ nid = page_to_nid(page);
+ if (!node_isset(nid, node_states[N_MEMORY]))
+ return NULL;
+
+ return page;
+}
+#endif
+
+static int gather_pte_stats(pmd_t *pmd, unsigned long addr,
+ unsigned long end, struct mm_walk *walk)
+{
+ struct numa_maps *md = walk->private;
+ struct vm_area_struct *vma = walk->vma;
+ spinlock_t *ptl;
+ pte_t *orig_pte;
+ pte_t *pte;
+
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+ ptl = pmd_trans_huge_lock(pmd, vma);
+ if (ptl) {
+ struct page *page;
+
+ page = can_gather_numa_stats_pmd(*pmd, vma, addr);
+ if (page)
+ gather_stats(page, md, pmd_dirty(*pmd),
+ HPAGE_PMD_SIZE/PAGE_SIZE);
+ spin_unlock(ptl);
+ return 0;
+ }
+
+ if (pmd_trans_unstable(pmd))
+ return 0;
+#endif
+ orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl);
+ do {
+ struct page *page = can_gather_numa_stats(*pte, vma, addr);
+ if (!page)
+ continue;
+ gather_stats(page, md, pte_dirty(*pte), 1);
+
+ } while (pte++, addr += PAGE_SIZE, addr != end);
+ pte_unmap_unlock(orig_pte, ptl);
+ cond_resched();
+ return 0;
+}
+#ifdef CONFIG_HUGETLB_PAGE
+static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
+ unsigned long addr, unsigned long end, struct mm_walk *walk)
+{
+ pte_t huge_pte = huge_ptep_get(pte);
+ struct numa_maps *md;
+ struct page *page;
+
+ if (!pte_present(huge_pte))
+ return 0;
+
+ page = pte_page(huge_pte);
+ if (!page)
+ return 0;
+
+ md = walk->private;
+ gather_stats(page, md, pte_dirty(huge_pte), 1);
+ return 0;
+}
+
+#else
+static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
+ unsigned long addr, unsigned long end, struct mm_walk *walk)
+{
+ return 0;
+}
+#endif
+
+/*
+ * Display pages allocated per node and memory policy via /proc.
+ */
+static int show_numa_map(struct seq_file *m, void *v)
+{
+ struct numa_maps_private *numa_priv = m->private;
+ struct proc_maps_private *proc_priv = &numa_priv->proc_maps;
+ struct vm_area_struct *vma = v;
+ struct numa_maps *md = &numa_priv->md;
+ struct file *file = vma->vm_file;
+ struct mm_struct *mm = vma->vm_mm;
+ struct mm_walk walk = {
+ .hugetlb_entry = gather_hugetlb_stats,
+ .pmd_entry = gather_pte_stats,
+ .private = md,
+ .mm = mm,
+ };
+ struct mempolicy *pol;
+ char buffer[64];
+ int nid;
+
+ if (!mm)
+ return 0;
+
+ /* Ensure we start with an empty set of numa_maps statistics. */
+ memset(md, 0, sizeof(*md));
+
+ pol = __get_vma_policy(vma, vma->vm_start);
+ if (pol) {
+ mpol_to_str(buffer, sizeof(buffer), pol);
+ mpol_cond_put(pol);
+ } else {
+ mpol_to_str(buffer, sizeof(buffer), proc_priv->task_mempolicy);
+ }
+
+ seq_printf(m, "%08lx %s", vma->vm_start, buffer);
+
+ if (file) {
+ seq_puts(m, " file=");
+ seq_file_path(m, file, "\n\t= ");
+ } else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) {
+ seq_puts(m, " heap");
+ } else if (is_stack(vma)) {
+ seq_puts(m, " stack");
+ }
+
+ if (is_vm_hugetlb_page(vma))
+ seq_puts(m, " huge");
+
+ /* mmap_sem is held by m_start */
+ walk_page_vma(vma, &walk);
+
+ 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(nid, N_MEMORY)
+ if (md->node[nid])
+ seq_printf(m, " N%d=%lu", nid, md->node[nid]);
+
+ seq_printf(m, " kernelpagesize_kB=%lu", vma_kernel_pagesize(vma) >> 10);
+out:
+ seq_putc(m, '\n');
+ m_cache_vma(m, vma);
+ return 0;
+}
+
+static const struct seq_operations proc_pid_numa_maps_op = {
+ .start = m_start,
+ .next = m_next,
+ .stop = m_stop,
+ .show = show_numa_map,
+};
+
+static int pid_numa_maps_open(struct inode *inode, struct file *file)
+{
+ return proc_maps_open(inode, file, &proc_pid_numa_maps_op,
+ sizeof(struct numa_maps_private));
+}
+
+const struct file_operations proc_pid_numa_maps_operations = {
+ .open = pid_numa_maps_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = proc_map_release,
+};
+
+#endif /* CONFIG_NUMA */