patch-2.1.51 linux/arch/ppc/kernel/ppc_htab.c

• Lines: 197
• Date: Sat Aug 16 09:51:08 1997
• Orig file: v2.1.50/linux/arch/ppc/kernel/ppc_htab.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.1.50/linux/arch/ppc/kernel/ppc_htab.c linux/arch/ppc/kernel/ppc_htab.c
@@ -0,0 +1,196 @@
+/*
+ * $Id: ppc_htab.c,v 1.4 1997/08/12 04:24:54 cort Exp $
+ * PowerPC hash table management proc entry.  Will show information
+ * about the current hash table and will allow changes to it.
+ *
+ * Written by Cort Dougan (cort@cs.nmt.edu)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/proc_fs.h>
+#include <linux/stat.h>
+
+#include <asm/uaccess.h>
+#include <asm/bitops.h>
+#include <asm/mmu.h>
+#include <asm/processor.h>
+#include <asm/residual.h>
+#include <asm/io.h>
+#include <asm/pgtable.h>
+
+static long ppc_htab_read(struct inode * inode, struct file * file,
+			   char * buf, unsigned long nbytes);
+static long ppc_htab_write(struct inode * inode, struct file * file,
+			    const char * buffer, unsigned long count);
+static long long ppc_htab_lseek(struct inode * inode, struct file * file, 
+				 long long offset, int orig);
+
+extern PTE *Hash, *Hash_end;
+extern unsigned long Hash_size, Hash_mask;
+
+static struct file_operations ppc_htab_operations = {
+    ppc_htab_lseek,	/* lseek   */
+    ppc_htab_read,	/* read	   */
+    ppc_htab_write,	/* write   */
+    NULL,		/* readdir */
+    NULL,		/* poll    */
+    NULL,		/* ioctl   */
+    NULL,		/* mmap	   */
+    NULL,		/* no special open code	   */
+    NULL,		/* no special release code */
+    NULL		/* can't fsync */
+};
+
+/*
+ * proc files can do almost nothing..
+ */
+struct inode_operations proc_ppc_htab_inode_operations = {
+    &ppc_htab_operations,  /* default proc file-ops */
+    NULL,	    /* create	   */
+    NULL,	    /* lookup	   */
+    NULL,	    /* link	   */
+    NULL,	    /* unlink	   */
+    NULL,	    /* symlink	   */
+    NULL,	    /* mkdir	   */
+    NULL,	    /* rmdir	   */
+    NULL,	    /* mknod	   */
+    NULL,	    /* rename	   */
+    NULL,	    /* readlink	   */
+    NULL,	    /* follow_link */
+    NULL,	    /* readpage	   */
+    NULL,	    /* writepage   */
+    NULL,	    /* bmap	   */
+    NULL,	    /* truncate	   */
+    NULL	    /* permission  */
+};
+
+
+/*
+ * print some useful info about the hash table.  This function
+ * is _REALLY_ slow (see the nested for loops below) but nothing
+ * in here should be really timing critical. -- Cort
+ */
+static long ppc_htab_read(struct inode * inode, struct file * file,
+			   char * buf, unsigned long nbytes)
+{
+	int n = 0, valid;
+	unsigned int kptes = 0, overflow = 0, uptes = 0;
+	PTE *ptr;
+	struct task_struct *p;
+	
+	if (nbytes < 0)
+		return -EINVAL;
+
+	/*
+	 * compute user/kernel pte's table this info can be
+	 * misleading since there can be valid (v bit set) entries
+	 * in the table but their vsid is used by no process (mm->context)
+	 * due to the way tlb invalidation is handled on the ppc
+	 * -- Cort
+	 */
+	for ( ptr = Hash ; ptr < (PTE *)(Hash+Hash_size) ; ptr+=sizeof(PTE))
+	{
+		if (ptr->v)
+		{
+			/* make sure someone is using this context/vsid */
+			for_each_task(p)
+			{
+				if ( (ptr->vsid >> 4) == p->mm->context )
+				{
+					valid = 1;
+					break;
+				}
+			}
+			if ( !valid )
+				continue;
+			/* user not allowed read or write */
+			if (ptr->pp == PP_RWXX)
+				kptes++;
+			else
+				uptes++;
+			if (ptr->h == 1)
+				overflow++;
+		}
+	}
+	n += sprintf( buf,
+		      "Size\t\t: %luKb\n"
+		      "Buckets\t\t: %lu\n"
+ 		      "Address\t\t: %08lx\n"
+		      "Entries\t\t: %lu\n"
+		      "User ptes\t: %u\n"
+		      "Kernel ptes\t: %u\n"
+		      "Overflows\t: %u\n"
+		      "Percent full\t: %%%lu\n",
+                      (unsigned long)(Hash_size>>10),
+		      (Hash_size/(sizeof(PTE)*8)),
+		      (unsigned long)Hash,
+		      Hash_size/sizeof(PTE),
+                      uptes,
+		      kptes,
+		      overflow,
+		      ((kptes+uptes)*100) / (Hash_size/sizeof(PTE))
+		);
+	/* if we're trying to read part of the file that isn't there */
+	if ( file->f_pos > n )
+		return -ENOMEM;
+	file->f_pos += n;
+	return n;
+}
+
+/*
+ * Can't _yet_ adjust the hash table size while running. -- Cort
+ */
+static long
+ppc_htab_write(struct inode * inode, struct file * file,
+		const char * buffer, unsigned long count)
+{
+	if ( current->uid != 0 )
+		return -EACCES;
+	else
+		return -ENOSYS;
+	return 0;
+}
+
+
+static long long
+ppc_htab_lseek(struct inode * inode, struct file * file, 
+				 long long offset, int orig)
+{
+    switch (orig) {
+    case 0:
+	file->f_pos = offset;
+	return(file->f_pos);
+    case 1:
+	file->f_pos += offset;
+	return(file->f_pos);
+    case 2:
+	return(-EINVAL);
+    default:
+	return(-EINVAL);
+    }
+}
+
+
+#if 0
+/*
+  for root.c
+  */
+static struct proc_dir_entry proc_root_ppc_htab = {
+	PROC_PPC_HTAB, 8, "ppc_htab",
+	S_IFREG | S_IRUGO, 1, 0, 0,
+	0, &proc_ppc_htab_inode_operations
+};
+#ifdef __powerpc__
+	proc_register(&proc_root, &proc_root_ppc_htab);
+#endif
+
+
+/* add to proc_fs.h
+   	PROC_PPC_HTAB,*/
+#endif