diff options
Diffstat (limited to 'fs/proc/page.c')
| -rw-r--r-- | fs/proc/page.c | 152 |
1 files changed, 113 insertions, 39 deletions
diff --git a/fs/proc/page.c b/fs/proc/page.c index 767d95a6d1b..e647c55275d 100644 --- a/fs/proc/page.c +++ b/fs/proc/page.c @@ -2,15 +2,19 @@ #include <linux/compiler.h> #include <linux/fs.h> #include <linux/init.h> +#include <linux/ksm.h> #include <linux/mm.h> #include <linux/mmzone.h> #include <linux/proc_fs.h> #include <linux/seq_file.h> +#include <linux/hugetlb.h> +#include <linux/kernel-page-flags.h> #include <asm/uaccess.h> #include "internal.h" #define KPMSIZE sizeof(u64) #define KPMMASK (KPMSIZE - 1) + /* /proc/kpagecount - an array exposing page counts * * Each entry is a u64 representing the corresponding @@ -32,20 +36,22 @@ static ssize_t kpagecount_read(struct file *file, char __user *buf, return -EINVAL; while (count > 0) { - ppage = NULL; if (pfn_valid(pfn)) ppage = pfn_to_page(pfn); - pfn++; - if (!ppage) + else + ppage = NULL; + if (!ppage || PageSlab(ppage)) pcount = 0; else pcount = page_mapcount(ppage); - if (put_user(pcount, out++)) { + if (put_user(pcount, out)) { ret = -EFAULT; break; } + pfn++; + out++; count -= KPMSIZE; } @@ -66,21 +72,104 @@ static const struct file_operations proc_kpagecount_operations = { * physical page flags. */ -/* These macros are used to decouple internal flags from exported ones */ - -#define KPF_LOCKED 0 -#define KPF_ERROR 1 -#define KPF_REFERENCED 2 -#define KPF_UPTODATE 3 -#define KPF_DIRTY 4 -#define KPF_LRU 5 -#define KPF_ACTIVE 6 -#define KPF_SLAB 7 -#define KPF_WRITEBACK 8 -#define KPF_RECLAIM 9 -#define KPF_BUDDY 10 +static inline u64 kpf_copy_bit(u64 kflags, int ubit, int kbit) +{ + return ((kflags >> kbit) & 1) << ubit; +} -#define kpf_copy_bit(flags, srcpos, dstpos) (((flags >> srcpos) & 1) << dstpos) +u64 stable_page_flags(struct page *page) +{ + u64 k; + u64 u; + + /* + * pseudo flag: KPF_NOPAGE + * it differentiates a memory hole from a page with no flags + */ + if (!page) + return 1 << KPF_NOPAGE; + + k = page->flags; + u = 0; + + /* + * pseudo flags for the well known (anonymous) memory mapped pages + * + * Note that page->_mapcount is overloaded in SLOB/SLUB/SLQB, so the + * simple test in page_mapped() is not enough. + */ + if (!PageSlab(page) && page_mapped(page)) + u |= 1 << KPF_MMAP; + if (PageAnon(page)) + u |= 1 << KPF_ANON; + if (PageKsm(page)) + u |= 1 << KPF_KSM; + + /* + * compound pages: export both head/tail info + * they together define a compound page's start/end pos and order + */ + if (PageHead(page)) + u |= 1 << KPF_COMPOUND_HEAD; + if (PageTail(page)) + u |= 1 << KPF_COMPOUND_TAIL; + if (PageHuge(page)) + u |= 1 << KPF_HUGE; + /* + * PageTransCompound can be true for non-huge compound pages (slab + * pages or pages allocated by drivers with __GFP_COMP) because it + * just checks PG_head/PG_tail, so we need to check PageLRU/PageAnon + * to make sure a given page is a thp, not a non-huge compound page. + */ + else if (PageTransCompound(page) && (PageLRU(compound_head(page)) || + PageAnon(compound_head(page)))) + u |= 1 << KPF_THP; + + /* + * Caveats on high order pages: page->_count will only be set + * -1 on the head page; SLUB/SLQB do the same for PG_slab; + * SLOB won't set PG_slab at all on compound pages. + */ + if (PageBuddy(page)) + u |= 1 << KPF_BUDDY; + + u |= kpf_copy_bit(k, KPF_LOCKED, PG_locked); + + u |= kpf_copy_bit(k, KPF_SLAB, PG_slab); + + u |= kpf_copy_bit(k, KPF_ERROR, PG_error); + u |= kpf_copy_bit(k, KPF_DIRTY, PG_dirty); + u |= kpf_copy_bit(k, KPF_UPTODATE, PG_uptodate); + u |= kpf_copy_bit(k, KPF_WRITEBACK, PG_writeback); + + u |= kpf_copy_bit(k, KPF_LRU, PG_lru); + u |= kpf_copy_bit(k, KPF_REFERENCED, PG_referenced); + u |= kpf_copy_bit(k, KPF_ACTIVE, PG_active); + u |= kpf_copy_bit(k, KPF_RECLAIM, PG_reclaim); + + u |= kpf_copy_bit(k, KPF_SWAPCACHE, PG_swapcache); + u |= kpf_copy_bit(k, KPF_SWAPBACKED, PG_swapbacked); + + u |= kpf_copy_bit(k, KPF_UNEVICTABLE, PG_unevictable); + u |= kpf_copy_bit(k, KPF_MLOCKED, PG_mlocked); + +#ifdef CONFIG_MEMORY_FAILURE + u |= kpf_copy_bit(k, KPF_HWPOISON, PG_hwpoison); +#endif + +#ifdef CONFIG_ARCH_USES_PG_UNCACHED + u |= kpf_copy_bit(k, KPF_UNCACHED, PG_uncached); +#endif + + u |= kpf_copy_bit(k, KPF_RESERVED, PG_reserved); + u |= kpf_copy_bit(k, KPF_MAPPEDTODISK, PG_mappedtodisk); + u |= kpf_copy_bit(k, KPF_PRIVATE, PG_private); + u |= kpf_copy_bit(k, KPF_PRIVATE_2, PG_private_2); + u |= kpf_copy_bit(k, KPF_OWNER_PRIVATE, PG_owner_priv_1); + u |= kpf_copy_bit(k, KPF_ARCH, PG_arch_1); + + return u; +}; static ssize_t kpageflags_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) @@ -90,7 +179,6 @@ static ssize_t kpageflags_read(struct file *file, char __user *buf, unsigned long src = *ppos; unsigned long pfn; ssize_t ret = 0; - u64 kflags, uflags; pfn = src / KPMSIZE; count = min_t(unsigned long, count, (max_pfn * KPMSIZE) - src); @@ -98,32 +186,18 @@ static ssize_t kpageflags_read(struct file *file, char __user *buf, return -EINVAL; while (count > 0) { - ppage = NULL; if (pfn_valid(pfn)) ppage = pfn_to_page(pfn); - pfn++; - if (!ppage) - kflags = 0; else - kflags = ppage->flags; - - uflags = kpf_copy_bit(KPF_LOCKED, PG_locked, kflags) | - kpf_copy_bit(kflags, KPF_ERROR, PG_error) | - kpf_copy_bit(kflags, KPF_REFERENCED, PG_referenced) | - kpf_copy_bit(kflags, KPF_UPTODATE, PG_uptodate) | - kpf_copy_bit(kflags, KPF_DIRTY, PG_dirty) | - kpf_copy_bit(kflags, KPF_LRU, PG_lru) | - kpf_copy_bit(kflags, KPF_ACTIVE, PG_active) | - kpf_copy_bit(kflags, KPF_SLAB, PG_slab) | - kpf_copy_bit(kflags, KPF_WRITEBACK, PG_writeback) | - kpf_copy_bit(kflags, KPF_RECLAIM, PG_reclaim) | - kpf_copy_bit(kflags, KPF_BUDDY, PG_buddy); - - if (put_user(uflags, out++)) { + ppage = NULL; + + if (put_user(stable_page_flags(ppage), out)) { ret = -EFAULT; break; } + pfn++; + out++; count -= KPMSIZE; } @@ -144,4 +218,4 @@ static int __init proc_page_init(void) proc_create("kpageflags", S_IRUSR, NULL, &proc_kpageflags_operations); return 0; } -module_init(proc_page_init); +fs_initcall(proc_page_init); |