Commit d3171200 authored Feb 27, 2017 by Gilad Ben-Yossef Committed by Linus Torvalds Feb 27, 2017

scatterlist: do not disable IRQs in sg_copy_buffer

Commit 50bed2e2 ("sg: disable interrupts inside sg_copy_buffer")
introduced disabling interrupts in sg_copy_buffer() since atomic uses of
miter required it due to use of kmap_atomic().

However, as commit 8290e2d2 ("scatterlist: atomic sg_mapping_iter()
no longer needs disabled IRQs") acknowledges disabling interrupts is no
longer needed for calls to kmap_atomic() and therefore unneeded for
miter ops either, so remove it from sg_copy_buffer().

Link: http://lkml.kernel.org/r/1486040150-14109-3-git-send-email-gilad@benyossef.com


Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: <ofir.drang@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 1d5210ef

lib/scatterlist.c

+0 −4

Original line number	Diff line number	Diff line
		@@ -651,7 +651,6 @@ size_t sg_copy_buffer(struct scatterlist sgl, unsigned int nents, void buf,
		{
		unsigned int offset = 0;
		struct sg_mapping_iter miter;
		unsigned long flags;
		unsigned int sg_flags = SG_MITER_ATOMIC;

		if (to_buffer)
		@@ -664,8 +663,6 @@ size_t sg_copy_buffer(struct scatterlist sgl, unsigned int nents, void buf,
		if (!sg_miter_skip(&miter, skip))
		return false;

		local_irq_save(flags);

		while ((offset < buflen) && sg_miter_next(&miter)) {
		unsigned int len;

		@@ -681,7 +678,6 @@ size_t sg_copy_buffer(struct scatterlist sgl, unsigned int nents, void buf,

		sg_miter_stop(&miter);

		local_irq_restore(flags);
		return offset;
		}
		EXPORT_SYMBOL(sg_copy_buffer);

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