Commit 9c78a73a authored by Stefan Wahren's avatar Stefan Wahren Committed by Greg Kroah-Hartman
Browse files

staging: vchiq_arm: introduce is_adjacent_block 



The check for an adjacent block is hard to read. So move it into a separate
inline function.

Reviewed-by: default avatarNicolas Saenz Julienne <nsaenz@kernel.org>
Signed-off-by: default avatarStefan Wahren <stefan.wahren@i2se.com>
Link: https://lore.kernel.org/r/1642968143-19281-4-git-send-email-stefan.wahren@i2se.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent e1a17ce8

drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c

+15 −4
Original line number Diff line number Diff line
@@ -189,6 +189,20 @@ cleanup_pagelistinfo(struct vchiq_pagelist_info *pagelistinfo) 
			  pagelistinfo->pagelist, pagelistinfo->dma_addr);

}



static inline bool

is_adjacent_block(u32 *addrs, u32 addr, unsigned int k)

{

	u32 tmp;



	if (!k)

		return false;



	tmp = (addrs[k - 1] & PAGE_MASK) +

	      (((addrs[k - 1] & ~PAGE_MASK) + 1) << PAGE_SHIFT);



	return tmp == (addr & PAGE_MASK);

}



/* There is a potential problem with partial cache lines (pages?)

 * at the ends of the block when reading. If the CPU accessed anything in

 * the same line (page?) then it may have pulled old data into the cache,
@@ -349,10 +363,7 @@ create_pagelist(char *buf, char __user *ubuf, 
		WARN_ON(len == 0);

		WARN_ON(i && (i != (dma_buffers - 1)) && (len & ~PAGE_MASK));

		WARN_ON(i && (addr & ~PAGE_MASK));

		if (k > 0 &&

		    ((addrs[k - 1] & PAGE_MASK) +

		     (((addrs[k - 1] & ~PAGE_MASK) + 1) << PAGE_SHIFT))

		    == (addr & PAGE_MASK))

		if (is_adjacent_block(addrs, addr, k))

			addrs[k - 1] += ((len + PAGE_SIZE - 1) >> PAGE_SHIFT);

		else

			addrs[k++] = (addr & PAGE_MASK) |