diff options
Diffstat (limited to '')
| -rw-r--r-- | fs/proc/task_mmu.c | 1977 |
1 files changed, 1977 insertions, 0 deletions
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c new file mode 100644 index 000000000..39b103807 --- /dev/null +++ b/fs/proc/task_mmu.c @@ -0,0 +1,1977 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <linux/pagewalk.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", atomic64_read(&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 *m_start(struct seq_file *m, loff_t *ppos) +{ + struct proc_maps_private *priv = m->private; + unsigned long last_addr = *ppos; + struct mm_struct *mm; + struct vm_area_struct *vma; + + /* See m_next(). 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)) { + put_task_struct(priv->task); + priv->task = NULL; + return NULL; + } + + if (mmap_read_lock_killable(mm)) { + mmput(mm); + put_task_struct(priv->task); + priv->task = NULL; + return ERR_PTR(-EINTR); + } + + hold_task_mempolicy(priv); + priv->tail_vma = get_gate_vma(mm); + + vma = find_vma(mm, last_addr); + if (vma) + return vma; + + return priv->tail_vma; +} + +static void *m_next(struct seq_file *m, void *v, loff_t *ppos) +{ + struct proc_maps_private *priv = m->private; + struct vm_area_struct *next, *vma = v; + + if (vma == priv->tail_vma) + next = NULL; + else if (vma->vm_next) + next = vma->vm_next; + else + next = priv->tail_vma; + + *ppos = next ? next->vm_start : -1UL; + + return next; +} + +static void m_stop(struct seq_file *m, void *v) +{ + struct proc_maps_private *priv = m->private; + struct mm_struct *mm = priv->mm; + + if (!priv->task) + return; + + release_task_mempolicy(priv); + mmap_read_unlock(mm); + mmput(mm); + 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); + 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 file_thp; + unsigned long swap; + unsigned long shared_hugetlb; + unsigned long private_hugetlb; + u64 pss; + u64 pss_anon; + u64 pss_file; + u64 pss_shmem; + u64 pss_locked; + u64 swap_pss; + bool check_shmem_swap; +}; + +static void smaps_page_accumulate(struct mem_size_stats *mss, + struct page *page, unsigned long size, unsigned long pss, + bool dirty, bool locked, bool private) +{ + mss->pss += pss; + + if (PageAnon(page)) + mss->pss_anon += pss; + else if (PageSwapBacked(page)) + mss->pss_shmem += pss; + else + mss->pss_file += pss; + + if (locked) + mss->pss_locked += pss; + + if (dirty || PageDirty(page)) { + if (private) + mss->private_dirty += size; + else + mss->shared_dirty += size; + } else { + if (private) + mss->private_clean += size; + else + mss->shared_clean += size; + } +} + +static void smaps_account(struct mem_size_stats *mss, struct page *page, + bool compound, bool young, bool dirty, bool locked, + bool migration) +{ + int i, nr = compound ? compound_nr(page) : 1; + unsigned long size = nr * PAGE_SIZE; + + /* + * First accumulate quantities that depend only on |size| and the type + * of the compound page. + */ + 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; + + /* + * Then accumulate quantities that may depend on sharing, or that may + * differ page-by-page. + * + * 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(). + * + * The page_mapcount() is called to get a snapshot of the mapcount. + * Without holding the page lock this snapshot can be slightly wrong as + * we cannot always read the mapcount atomically. It is not safe to + * call page_mapcount() even with PTL held if the page is not mapped, + * especially for migration entries. Treat regular migration entries + * as mapcount == 1. + */ + if ((page_count(page) == 1) || migration) { + smaps_page_accumulate(mss, page, size, size << PSS_SHIFT, dirty, + locked, true); + return; + } + for (i = 0; i < nr; i++, page++) { + int mapcount = page_mapcount(page); + unsigned long pss = PAGE_SIZE << PSS_SHIFT; + if (mapcount >= 2) + pss /= mapcount; + smaps_page_accumulate(mss, page, PAGE_SIZE, pss, dirty, locked, + mapcount < 2); + } +} + +#ifdef CONFIG_SHMEM +static int smaps_pte_hole(unsigned long addr, unsigned long end, + __always_unused int depth, 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; +} +#else +#define smaps_pte_hole NULL +#endif /* CONFIG_SHMEM */ + +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; + bool locked = !!(vma->vm_flags & VM_LOCKED); + struct page *page = NULL; + bool migration = false, young = false, dirty = false; + + if (pte_present(*pte)) { + page = vm_normal_page(vma, addr, *pte); + young = pte_young(*pte); + dirty = pte_dirty(*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)) { + migration = true; + 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 = xa_load(&vma->vm_file->f_mapping->i_pages, + linear_page_index(vma, addr)); + if (xa_is_value(page)) + mss->swap += PAGE_SIZE; + return; + } + + if (!page) + return; + + smaps_account(mss, page, false, young, dirty, locked, migration); +} + +#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; + bool locked = !!(vma->vm_flags & VM_LOCKED); + struct page *page = NULL; + bool migration = false; + + if (pmd_present(*pmd)) { + /* FOLL_DUMP will return -EFAULT on huge zero page */ + page = follow_trans_huge_pmd(vma, addr, pmd, FOLL_DUMP); + } else if (unlikely(thp_migration_supported() && is_swap_pmd(*pmd))) { + swp_entry_t entry = pmd_to_swp_entry(*pmd); + + if (is_migration_entry(entry)) { + migration = true; + page = migration_entry_to_page(entry); + } + } + 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 + mss->file_thp += HPAGE_PMD_SIZE; + + smaps_account(mss, page, true, pmd_young(*pmd), pmd_dirty(*pmd), + locked, migration); +} +#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) { + smaps_pmd_entry(pmd, addr, walk); + spin_unlock(ptl); + goto out; + } + + if (pmd_trans_unstable(pmd)) + goto out; + /* + * The mmap_lock 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", + [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_ARM64_BTI + [ilog2(VM_ARM64_BTI)] = "bt", +#endif +#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_ARM64_MTE + [ilog2(VM_MTE)] = "mt", + [ilog2(VM_MTE_ALLOWED)] = "", +#endif +#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) { + if (page_mapcount(page) >= 2 || hugetlb_pmd_shared(pte)) + mss->shared_hugetlb += huge_page_size(hstate_vma(vma)); + else + mss->private_hugetlb += huge_page_size(hstate_vma(vma)); + } + return 0; +} +#else +#define smaps_hugetlb_range NULL +#endif /* HUGETLB_PAGE */ + +static const struct mm_walk_ops smaps_walk_ops = { + .pmd_entry = smaps_pte_range, + .hugetlb_entry = smaps_hugetlb_range, +}; + +static const struct mm_walk_ops smaps_shmem_walk_ops = { + .pmd_entry = smaps_pte_range, + .hugetlb_entry = smaps_hugetlb_range, + .pte_hole = smaps_pte_hole, +}; + +/* + * Gather mem stats from @vma with the indicated beginning + * address @start, and keep them in @mss. + * + * Use vm_start of @vma as the beginning address if @start is 0. + */ +static void smap_gather_stats(struct vm_area_struct *vma, + struct mem_size_stats *mss, unsigned long start) +{ + const struct mm_walk_ops *ops = &smaps_walk_ops; + + /* Invalid start */ + if (start >= vma->vm_end) + return; + +#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 (!start && (!shmem_swapped || (vma->vm_flags & VM_SHARED) || + !(vma->vm_flags & VM_WRITE))) { + mss->swap += shmem_swapped; + } else { + mss->check_shmem_swap = true; + ops = &smaps_shmem_walk_ops; + } + } +#endif + /* mmap_lock is held in m_start */ + if (!start) + walk_page_vma(vma, ops, mss); + else + walk_page_range(vma->vm_mm, start, vma->vm_end, ops, mss); +} + +#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, + bool rollup_mode) +{ + SEQ_PUT_DEC("Rss: ", mss->resident); + SEQ_PUT_DEC(" kB\nPss: ", mss->pss >> PSS_SHIFT); + if (rollup_mode) { + /* + * These are meaningful only for smaps_rollup, otherwise two of + * them are zero, and the other one is the same as Pss. + */ + SEQ_PUT_DEC(" kB\nPss_Anon: ", + mss->pss_anon >> PSS_SHIFT); + SEQ_PUT_DEC(" kB\nPss_File: ", + mss->pss_file >> PSS_SHIFT); + SEQ_PUT_DEC(" kB\nPss_Shmem: ", + mss->pss_shmem >> 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\nFilePmdMapped: ", mss->file_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, 0); + + 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, false); + + seq_printf(m, "THPeligible: %d\n", + transparent_hugepage_active(vma)); + + if (arch_pkeys_enabled()) + seq_printf(m, "ProtectionKey: %8u\n", vma_pkey(vma)); + show_smap_vma_flags(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)); + + ret = mmap_read_lock_killable(mm); + if (ret) + goto out_put_mm; + + hold_task_mempolicy(priv); + + for (vma = priv->mm->mmap; vma;) { + smap_gather_stats(vma, &mss, 0); + last_vma_end = vma->vm_end; + + /* + * Release mmap_lock temporarily if someone wants to + * access it for write request. + */ + if (mmap_lock_is_contended(mm)) { + mmap_read_unlock(mm); + ret = mmap_read_lock_killable(mm); + if (ret) { + release_task_mempolicy(priv); + goto out_put_mm; + } + + /* + * After dropping the lock, there are four cases to + * consider. See the following example for explanation. + * + * +------+------+-----------+ + * | VMA1 | VMA2 | VMA3 | + * +------+------+-----------+ + * | | | | + * 4k 8k 16k 400k + * + * Suppose we drop the lock after reading VMA2 due to + * contention, then we get: + * + * last_vma_end = 16k + * + * 1) VMA2 is freed, but VMA3 exists: + * + * find_vma(mm, 16k - 1) will return VMA3. + * In this case, just continue from VMA3. + * + * 2) VMA2 still exists: + * + * find_vma(mm, 16k - 1) will return VMA2. + * Iterate the loop like the original one. + * + * 3) No more VMAs can be found: + * + * find_vma(mm, 16k - 1) will return NULL. + * No more things to do, just break. + * + * 4) (last_vma_end - 1) is the middle of a vma (VMA'): + * + * find_vma(mm, 16k - 1) will return VMA' whose range + * contains last_vma_end. + * Iterate VMA' from last_vma_end. + */ + vma = find_vma(mm, last_vma_end - 1); + /* Case 3 above */ + if (!vma) + break; + + /* Case 1 above */ + if (vma->vm_start >= last_vma_end) + continue; + + /* Case 4 above */ + if (vma->vm_end > last_vma_end) + smap_gather_stats(vma, &mss, last_vma_end); + } + /* Case 2 above */ + vma = vma->vm_next; + } + + show_vma_header_prefix(m, priv->mm->mmap ? priv->mm->mmap->vm_start : 0, + last_vma_end, 0, 0, 0, 0); + seq_pad(m, ' '); + seq_puts(m, "[rollup]\n"); + + __show_smap(m, &mss, true); + + release_task_mempolicy(priv); + mmap_read_unlock(mm); + +out_put_mm: + 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 + +#define is_cow_mapping(flags) (((flags) & (VM_SHARED | VM_MAYWRITE)) == VM_MAYWRITE) + +static inline bool pte_is_pinned(struct vm_area_struct *vma, unsigned long addr, pte_t pte) +{ + struct page *page; + + if (!pte_write(pte)) + return false; + if (!is_cow_mapping(vma->vm_flags)) + return false; + if (likely(!atomic_read(&vma->vm_mm->has_pinned))) + return false; + page = vm_normal_page(vma, addr, pte); + if (!page) + return false; + return page_maybe_dma_pinned(page); +} + +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)) { + pte_t old_pte; + + if (pte_is_pinned(vma, addr, ptent)) + return; + old_pte = ptep_modify_prot_start(vma, addr, pte); + ptent = pte_wrprotect(old_pte); + ptent = pte_clear_soft_dirty(ptent); + ptep_modify_prot_commit(vma, addr, pte, old_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 const struct mm_walk_ops clear_refs_walk_ops = { + .pmd_entry = clear_refs_pte_range, + .test_walk = clear_refs_test_walk, +}; + +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; + 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 mmu_notifier_range range; + struct clear_refs_private cp = { + .type = type, + }; + + if (mmap_write_lock_killable(mm)) { + count = -EINTR; + goto out_mm; + } + if (type == CLEAR_REFS_MM_HIWATER_RSS) { + /* + * 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); + goto out_unlock; + } + + if (type == CLEAR_REFS_SOFT_DIRTY) { + for (vma = mm->mmap; vma; vma = vma->vm_next) { + if (!(vma->vm_flags & VM_SOFTDIRTY)) + continue; + vma->vm_flags &= ~VM_SOFTDIRTY; + vma_set_page_prot(vma); + } + + inc_tlb_flush_pending(mm); + mmu_notifier_range_init(&range, MMU_NOTIFY_SOFT_DIRTY, + 0, NULL, mm, 0, -1UL); + mmu_notifier_invalidate_range_start(&range); + } + walk_page_range(mm, 0, mm->highest_vm_end, &clear_refs_walk_ops, + &cp); + if (type == CLEAR_REFS_SOFT_DIRTY) { + mmu_notifier_invalidate_range_end(&range); + flush_tlb_mm(mm); + dec_tlb_flush_pending(mm); + } +out_unlock: + mmap_write_unlock(mm); +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, + __always_unused int depth, 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; + bool migration = false; + + if (pte_present(pte)) { + if (pm->show_pfn) + frame = pte_pfn(pte); + flags |= PM_PRESENT; + page = vm_normal_page(vma, addr, pte); + 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)) { + migration = true; + 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 && !migration && 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 + bool migration = false; + + 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)); + migration = is_migration_entry(entry); + page = migration_entry_to_page(entry); + } +#endif + + if (page && !migration && 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; +} +#else +#define pagemap_hugetlb_range NULL +#endif /* HUGETLB_PAGE */ + +static const struct mm_walk_ops pagemap_ops = { + .pmd_entry = pagemap_pmd_range, + .pte_hole = pagemap_pte_hole, + .hugetlb_entry = pagemap_hugetlb_range, +}; + +/* + * /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; + 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; + + src = *ppos; + svpfn = src / PM_ENTRY_BYTES; + end_vaddr = mm->task_size; + + /* watch out for wraparound */ + start_vaddr = end_vaddr; + if (svpfn <= (ULONG_MAX >> PAGE_SHIFT)) + start_vaddr = untagged_addr(svpfn << PAGE_SHIFT); + + /* Ensure the address is inside the task */ + if (start_vaddr > mm->task_size) + 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; + ret = mmap_read_lock_killable(mm); + if (ret) + goto out_free; + ret = walk_page_range(mm, start_vaddr, end, &pagemap_ops, &pm); + mmap_read_unlock(mm); + 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 + +static const struct mm_walk_ops show_numa_ops = { + .hugetlb_entry = gather_hugetlb_stats, + .pmd_entry = gather_pte_stats, +}; + +/* + * 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 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_lock is held by m_start */ + walk_page_vma(vma, &show_numa_ops, 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(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'); + 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 */ |