firewire: ohci: replace vm_map_ram() with vmap() (51b04d59) · Commits · 戴 / test

vm_map_ram() is intended for short-lived objects, so using it for the AR buffers could fragment address space, especially on a 32-bit machine. For an allocation that lives as long as the device, vmap() is the better choice. Signed-off-by:

Clemens Ladisch <clemens@ladisch.de> Signed-off-by:

Stefan Richter <stefanr@s5r6.in-berlin.de>

drivers/firewire/ohci.c

+2 −4

Original line number	Diff line number	Diff line
		@@ -689,8 +689,7 @@ static void ar_context_release(struct ar_context *ctx)
		{
		unsigned int i;

		if (ctx->buffer)
		vm_unmap_ram(ctx->buffer, AR_BUFFERS + AR_WRAPAROUND_PAGES);
		vunmap(ctx->buffer);

		for (i = 0; i < AR_BUFFERS; i++)
		if (ctx->pages[i]) {
		@@ -1018,8 +1017,7 @@ static int ar_context_init(struct ar_context ctx, struct fw_ohci ohci,
		pages[i] = ctx->pages[i];
		for (i = 0; i < AR_WRAPAROUND_PAGES; i++)
		pages[AR_BUFFERS + i] = ctx->pages[i];
		ctx->buffer = vm_map_ram(pages, AR_BUFFERS + AR_WRAPAROUND_PAGES,
		-1, PAGE_KERNEL);
		ctx->buffer = vmap(pages, ARRAY_SIZE(pages), VM_MAP, PAGE_KERNEL);
		if (!ctx->buffer)
		goto out_of_memory;

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