Re: mmap over nfs leads to excessive system load

From: Chuck Lever
Date: Thu Nov 17 2005 - 12:01:52 EST

Trond Myklebust wrote:
I had a quick look at nfs_file_direct_write(), and among other things,
it would appear that it is not doing any of the usual overflow checks on
*pos and the count size (see generic_write_checks()). In particular,
checks are missing against overflow vs. MAX_NON_LFS if O_LARGEFILE is
not set (and also against overflow vs. s_maxbytes, but that is less
relevant here).

the architecture is to allow the NFS protocol and server to do these checks. begin:vcard
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