From 11ca77cdcca17cec909d2b97404ddacfec0acafd Mon Sep 17 00:00:00 2001 From: Tyler Fanelli Date: Tue, 19 Sep 2023 22:40:01 -0400 Subject: [PATCH] docs/fuse-io: Document the usage of DIRECT_IO_ALLOW_MMAP By default, shared mmap is disabled in FUSE DIRECT_IO mode. However, when the DIRECT_IO_ALLOW_MMAP flag is enabled in the FUSE_INIT reply, shared mmap is allowed. Signed-off-by: Tyler Fanelli Signed-off-by: Miklos Szeredi --- Documentation/filesystems/fuse-io.rst | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/Documentation/filesystems/fuse-io.rst b/Documentation/filesystems/fuse-io.rst index 255a368fe534..6464de4266ad 100644 --- a/Documentation/filesystems/fuse-io.rst +++ b/Documentation/filesystems/fuse-io.rst @@ -15,7 +15,8 @@ The direct-io mode can be selected with the FOPEN_DIRECT_IO flag in the FUSE_OPEN reply. In direct-io mode the page cache is completely bypassed for reads and writes. -No read-ahead takes place. Shared mmap is disabled. +No read-ahead takes place. Shared mmap is disabled by default. To allow shared +mmap, the FUSE_DIRECT_IO_ALLOW_MMAP flag may be enabled in the FUSE_INIT reply. In cached mode reads may be satisfied from the page cache, and data may be read-ahead by the kernel to fill the cache. The cache is always kept consistent