first commit

1 files changed, 294 insertions, 0 deletions

diff --git a/fs/proc/page.c b/fs/proc/page.c
new file mode 100644
index 000000000..1a10de230
--- /dev/null
+++ b/fs/proc/page.c
@@ -0,0 +1,294 @@
+#include <linux/bootmem.h>
+#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 <linux/swap.h>
+#include <linux/swapops.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
+ * physical page count.
+ */
+static ssize_t kpagecount_read(struct file *file, char __user *buf,
+			     size_t count, loff_t *ppos)
+{
+	u64 __user *out = (u64 __user *)buf;
+	struct page *ppage;
+	unsigned long src = *ppos;
+	unsigned long pfn;
+	unsigned long max_pfn_kpmsize = max_pfn * KPMSIZE;
+	ssize_t ret = 0;
+	u64 pcount;
+
+	pfn = src / KPMSIZE;
+	if(src != max_pfn_kpmsize){
+        count = min_t(size_t, count, max_pfn_kpmsize - src);
+	}
+	
+	if (src & KPMMASK || count & KPMMASK)
+		return -EINVAL;
+
+	while (count > 0) {
+		if (pfn_valid(pfn))
+			ppage = pfn_to_page(pfn);
+		else
+			ppage = NULL;
+		if (!ppage || PageSlab(ppage))
+			pcount = 0;
+		else
+			pcount = page_mapcount(ppage);
+
+		if (put_user(pcount, out)) {
+			ret = -EFAULT;
+			break;
+		}
+
+		pfn++;
+		out++;
+		count -= KPMSIZE;
+	}
+
+	*ppos += (char __user *)out - buf;
+	if (!ret)
+		ret = (char __user *)out - buf;
+	return ret;
+}
+
+static const struct file_operations proc_kpagecount_operations = {
+	.llseek = mem_lseek,
+	.read = kpagecount_read,
+};
+
+#ifdef CONFIG_SWAP
+extern struct swap_info_struct *swap_info_get(swp_entry_t entry);
+extern void swap_info_unlock(struct swap_info_struct *si);
+
+static inline unsigned char swap_count(unsigned char ent)
+{
+	return ent & ~SWAP_HAS_CACHE;	/* may include SWAP_HAS_CONT flag */
+}
+
+/* /proc/kpageswapn - an array exposing page swap counts
+ *
+ * Each entry is a u64 representing the corresponding
+ * physical page swap count.
+ */
+static ssize_t kpageswapn_read(struct file *file, char __user *buf,
+			     size_t count, loff_t *ppos)
+{
+	u64 __user *out = (u64 __user *)buf;
+	unsigned long src = *ppos, dst;
+	swp_entry_t swap_entry;
+	ssize_t ret = 0;
+	struct swap_info_struct *p;
+
+	dst = src / KPMSIZE;
+	/* Format the swap entry from the corresponding pagemap value */
+	swap_entry = swp_entry(dst >> (SWP_TYPE_SHIFT(swap_entry) + RADIX_TREE_EXCEPTIONAL_SHIFT), dst & SWP_OFFSET_MASK(swap_entry));
+	
+	//printk(KERN_INFO "kpageswapn_read src: %lx\n", src);
+	//printk(KERN_INFO "kpageswapn_read swap entry: %lx\n", swap_entry.val);
+	
+	if (src & KPMMASK || count & KPMMASK) {
+		printk(KERN_INFO "kpageswapn_read return EINVAL\n");
+		return -EINVAL;
+	}
+
+	p = swap_info_get(swap_entry);
+	if (p) {
+		u64 swapcount = swap_count(p->swap_map[swp_offset(swap_entry)]);
+		if (put_user(swapcount, out)) {
+			printk(KERN_INFO "kpageswapn_read put user failed\n");
+			ret = -EFAULT;
+		}
+		swap_info_unlock(p);
+	} else {
+		printk(KERN_INFO "kpageswapn_read swap_info_get failed\n");
+		ret = -EFAULT;
+	}
+
+	if (!ret) {
+		*ppos += KPMSIZE;
+		ret = KPMSIZE;
+	}
+	return ret;
+}
+
+static const struct file_operations proc_kpageswapn_operations = {
+	.llseek = mem_lseek,
+	.read = kpageswapn_read,
+};
+#endif // CONFIG_SWAP
+
+/* /proc/kpageflags - an array exposing page flags
+ *
+ * Each entry is a u64 representing the corresponding
+ * physical page flags.
+ */
+
+static inline u64 kpf_copy_bit(u64 kflags, int ubit, int kbit)
+{
+	return ((kflags >> kbit) & 1) << ubit;
+}
+
+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 to make
+	 * sure a given page is a thp, not a non-huge compound page.
+	 */
+	else if (PageTransCompound(page) && PageLRU(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)
+{
+	u64 __user *out = (u64 __user *)buf;
+	struct page *ppage;
+	unsigned long src = *ppos;
+	unsigned long pfn;
+	unsigned long max_pfn_kpmsize = max_pfn * KPMSIZE;
+	ssize_t ret = 0;
+
+	pfn = src / KPMSIZE;
+	if(src != max_pfn_kpmsize){
+	    count = min_t(unsigned long, count, max_pfn_kpmsize - src);
+	}
+	
+	if (src & KPMMASK || count & KPMMASK)
+		return -EINVAL;
+
+	while (count > 0) {
+		if (pfn_valid(pfn))
+			ppage = pfn_to_page(pfn);
+		else
+			ppage = NULL;
+
+		if (put_user(stable_page_flags(ppage), out)) {
+			ret = -EFAULT;
+			break;
+		}
+
+		pfn++;
+		out++;
+		count -= KPMSIZE;
+	}
+
+	*ppos += (char __user *)out - buf;
+	if (!ret)
+		ret = (char __user *)out - buf;
+	return ret;
+}
+
+static const struct file_operations proc_kpageflags_operations = {
+	.llseek = mem_lseek,
+	.read = kpageflags_read,
+};
+
+static int __init proc_page_init(void)
+{
+	proc_create("kpagecount", S_IRUSR, NULL, &proc_kpagecount_operations);
+#ifdef CONFIG_SWAP
+	proc_create("kpageswapn", S_IRUSR, NULL, &proc_kpageswapn_operations);
+#endif // CONFIG_SWAP
+	proc_create("kpageflags", S_IRUSR, NULL, &proc_kpageflags_operations);
+	return 0;
+}
+module_init(proc_page_init);