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From: Andrey Smetanin <asmetanin@virtuozzo.com>
To: qemu-devel@nongnu.org
Subject: [Qemu-devel] Question: cpu_physical_memory_map() and atomic test and set bit pattern
Date: Mon, 3 Aug 2015 13:38:38 +0300	[thread overview]
Message-ID: <55BF44AE.7020909@virtuozzo.com> (raw)

Hello, QEMU Developers!

cpu_physical_memory_map() calls directly addess_space_map() which has 
comment "Use only for reads OR writes - not for read-modify-write 
operations."

Why there is such restriction (only read or write access) in 
addess_space_map()/cpu_physical_memory_map() ?
How to transparently atomically test and set bit of guest memory inside 
QEMU host?
Is there any API for that pattern ? Or may I use cpu_physical_memory_map 
with is_write = 1 for that safely ?


Thanks,
Andrey

                 reply	other threads:[~2015-08-03 10:53 UTC|newest]

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