mirrors
/
linux-stable
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
1
0
Fork 0
Code Issues Releases Wiki Activity

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: Nicolas Saenz Julienne <nsaenz@kernel.org>
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Link: https://lore.kernel.org/r/1642968143-19281-4-git-send-email-stefan.wahren@i2se.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Stefan Wahren 2022-01-23 21:02:08 +01:00 committed by Greg Kroah-Hartman
parent e1a17ce82f
commit 9c78a73a5f
1 changed files with 15 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

19
drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c
View File

@ -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) |