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-rw-r--r--fs/proc/page.c162
1 files changed, 127 insertions, 35 deletions
diff --git a/fs/proc/page.c b/fs/proc/page.c
index e9983837d08d..2707c6c7a20f 100644
--- a/fs/proc/page.c
+++ b/fs/proc/page.c
@@ -6,11 +6,13 @@
#include <linux/mmzone.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
+#include <linux/hugetlb.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 +34,22 @@ 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++;
+ else
+ ppage = NULL;
if (!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;
}
@@ -68,19 +72,122 @@ static const struct file_operations proc_kpagecount_operations = {
/* 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
+#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
+
+/* 11-20: new additions in 2.6.31 */
+#define KPF_MMAP 11
+#define KPF_ANON 12
+#define KPF_SWAPCACHE 13
+#define KPF_SWAPBACKED 14
+#define KPF_COMPOUND_HEAD 15
+#define KPF_COMPOUND_TAIL 16
+#define KPF_HUGE 17
+#define KPF_UNEVICTABLE 18
+#define KPF_NOPAGE 20
+
+/* kernel hacking assistances
+ * WARNING: subject to change, never rely on them!
+ */
+#define KPF_RESERVED 32
+#define KPF_MLOCKED 33
+#define KPF_MAPPEDTODISK 34
+#define KPF_PRIVATE 35
+#define KPF_PRIVATE_2 36
+#define KPF_OWNER_PRIVATE 37
+#define KPF_ARCH 38
+#define KPF_UNCACHED 39
+
+static inline u64 kpf_copy_bit(u64 kflags, int ubit, int kbit)
+{
+ return ((kflags >> kbit) & 1) << ubit;
+}
-#define kpf_copy_bit(flags, dstpos, srcpos) (((flags >> srcpos) & 1) << dstpos)
+static u64 get_uflags(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;
+
+ /*
+ * 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;
+
+ u |= kpf_copy_bit(k, KPF_LOCKED, PG_locked);
+
+ /*
+ * Caveats on high order pages:
+ * PG_buddy will only be set on the head page; SLUB/SLQB do the same
+ * for PG_slab; SLOB won't set PG_slab at all on compound pages.
+ */
+ u |= kpf_copy_bit(k, KPF_SLAB, PG_slab);
+ u |= kpf_copy_bit(k, KPF_BUDDY, PG_buddy);
+
+ 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_IA64_UNCACHED_ALLOCATOR
+ 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 +197,6 @@ 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 +204,18 @@ 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(kflags, KPF_LOCKED, PG_locked) |
- 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(get_uflags(ppage), out)) {
ret = -EFAULT;
break;
}
+ pfn++;
+ out++;
count -= KPMSIZE;
}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-21 12:00:39 +0100