6e0c64f4dd
dev_name always dereferences its argument, so it should not be called if the argument is NULL. The function indeed later tests the argument for being NULL. The semantic match that finds this problem is as follows: (http://coccinelle.lip6.fr/) // <smpl> @@ expression dev,E; @@ *dev_name(dev) ... when != dev = E ( *dev == NULL | *dev != NULL ) // </smpl> Signed-off-by: Julia Lawall <julia@diku.dk> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
75 lines
2 KiB
C
75 lines
2 KiB
C
/* MN10300 Dynamic DMA mapping support
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*
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* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
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* Written by David Howells (dhowells@redhat.com)
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* Derived from: arch/i386/kernel/pci-dma.c
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public Licence
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* as published by the Free Software Foundation; either version
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* 2 of the Licence, or (at your option) any later version.
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*/
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#include <linux/types.h>
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#include <linux/mm.h>
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#include <linux/string.h>
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#include <linux/pci.h>
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#include <linux/gfp.h>
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#include <asm/io.h>
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static unsigned long pci_sram_allocated = 0xbc000000;
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void *dma_alloc_coherent(struct device *dev, size_t size,
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dma_addr_t *dma_handle, int gfp)
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{
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unsigned long addr;
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void *ret;
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pr_debug("dma_alloc_coherent(%s,%zu,%x)\n",
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dev ? dev_name(dev) : "?", size, gfp);
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if (0xbe000000 - pci_sram_allocated >= size) {
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size = (size + 255) & ~255;
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addr = pci_sram_allocated;
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pci_sram_allocated += size;
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ret = (void *) addr;
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goto done;
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}
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/* ignore region specifiers */
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gfp &= ~(__GFP_DMA | __GFP_HIGHMEM);
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if (dev == NULL || dev->coherent_dma_mask < 0xffffffff)
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gfp |= GFP_DMA;
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addr = __get_free_pages(gfp, get_order(size));
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if (!addr)
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return NULL;
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/* map the coherent memory through the uncached memory window */
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ret = (void *) (addr | 0x20000000);
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/* fill the memory with obvious rubbish */
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memset((void *) addr, 0xfb, size);
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/* write back and evict all cache lines covering this region */
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mn10300_dcache_flush_inv_range2(virt_to_phys((void *) addr), PAGE_SIZE);
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done:
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*dma_handle = virt_to_bus((void *) addr);
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printk("dma_alloc_coherent() = %p [%x]\n", ret, *dma_handle);
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return ret;
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}
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EXPORT_SYMBOL(dma_alloc_coherent);
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void dma_free_coherent(struct device *dev, size_t size, void *vaddr,
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dma_addr_t dma_handle)
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{
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unsigned long addr = (unsigned long) vaddr & ~0x20000000;
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if (addr >= 0x9c000000)
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return;
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free_pages(addr, get_order(size));
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}
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EXPORT_SYMBOL(dma_free_coherent);
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