patch-2.3.30 linux/drivers/char/zr36120_mem.c

• Lines: 129
• Date: Sat Nov 27 15:27:48 1999
• Orig file: v2.3.29/linux/drivers/char/zr36120_mem.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.3.29/linux/drivers/char/zr36120_mem.c linux/drivers/char/zr36120_mem.c
@@ -0,0 +1,128 @@
+/*
+    zr36120_mem.c - Zoran 36120/36125 based framegrabbers
+
+    Copyright (C) 1998-1999 Pauline Middelink <middelin@polyware.nl>
+
+    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.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+#include <linux/config.h>
+#include <linux/mm.h>
+#include <linux/pci.h>
+#include <linux/wrapper.h>
+#include <asm/io.h>
+#ifdef CONFIG_BIGPHYS_AREA
+#include <linux/bigphysarea.h>
+#endif
+
+#include "zr36120.h"
+#include "zr36120_mem.h"
+
+/* ----------------------------------------------------------------------- */
+/* Memory functions							   */
+/* shamelessly stolen and adapted from bttv.c				   */
+/* ----------------------------------------------------------------------- */
+
+/*
+ * convert virtual user memory address to physical address
+ * (virt_to_phys only works for kmalloced kernel memory)
+ */
+inline unsigned long uvirt_to_phys(unsigned long adr)
+{
+	pgd_t *pgd;
+	pmd_t *pmd;
+	pte_t *ptep, pte;
+
+	pgd = pgd_offset(current->mm, adr);
+	if (pgd_none(*pgd))
+		return 0;
+	pmd = pmd_offset(pgd, adr);
+	if (pmd_none(*pmd))
+		return 0;
+	ptep = pte_offset(pmd, adr/*&(~PGDIR_MASK)*/);
+	pte = *ptep;
+	/* Note; page_address will panic for us if the page is high */
+        if(pte_present(pte))
+        	return page_address(pte_page(pte))|(adr&(PAGE_SIZE-1));
+	return 0;
+}
+
+/*
+ * vmalloced address to physical address
+ */
+inline unsigned long kvirt_to_phys(unsigned long adr)
+{
+	return uvirt_to_phys(VMALLOC_VMADDR(adr));
+}
+
+/*
+ * vmalloced address to bus address
+ */
+inline unsigned long kvirt_to_bus(unsigned long adr)
+{
+	return virt_to_bus(phys_to_virt(kvirt_to_phys(adr)));
+}
+
+inline int order(unsigned long size)
+{
+	int ordr = 0;
+	size = (size+PAGE_SIZE-1)/PAGE_SIZE;
+	while (size) {
+		size /= 2;
+		ordr++;
+	}
+	return ordr;
+}
+
+void* bmalloc(unsigned long size)
+{
+	void* mem;
+#ifdef CONFIG_BIGPHYS_AREA
+	mem = bigphysarea_alloc_pages(size/PAGE_SIZE, 1, GFP_KERNEL);
+#else
+	/*
+	 * The following function got a lot of memory at boottime,
+	 * so we know its always there...
+	 */
+	mem = (void*)__get_free_pages(GFP_USER,order(size));
+#endif
+	if (mem) {
+		unsigned long adr = (unsigned long)mem;
+		while (size > 0) {
+			mem_map_reserve(MAP_NR(phys_to_virt(adr)));
+			adr += PAGE_SIZE;
+			size -= PAGE_SIZE;
+		}
+	}
+	return mem;
+}
+
+void bfree(void* mem, unsigned long size)
+{
+	if (mem) {
+		unsigned long adr = (unsigned long)mem;
+		unsigned long siz = size;
+		while (siz > 0) {
+			mem_map_unreserve(MAP_NR(phys_to_virt(adr)));
+			adr += PAGE_SIZE;
+			siz -= PAGE_SIZE;
+		}
+#ifdef CONFIG_BIGPHYS_AREA
+		bigphysarea_free_pages(mem);
+#else
+		free_pages((unsigned long)mem,order(size));
+#endif
+	}
+}