From 11b4d66ea3313d9b03a83b80458ddee64990e3c3 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Fri, 27 Jul 2018 11:19:10 -0400 Subject: NFSD: Handle full-length symlinks I've given up on the idea of zero-copy handling of SYMLINK on the server side. This is because the Linux VFS symlink API requires the symlink pathname to be in a NUL-terminated kmalloc'd buffer. The NUL-termination is going to be problematic (watching out for landing on a page boundary and dealing with a 4096-byte pathname). I don't believe that SYMLINK creation is on a performance path or is requested frequently enough that it will cause noticeable CPU cache pollution due to data copies. There will be two places where a transport callout will be necessary to fill in the rqstp: one will be in the svc_fill_symlink_pathname() helper that is used by NFSv2 and NFSv3, and the other will be in nfsd4_decode_create(). Signed-off-by: Chuck Lever Signed-off-by: J. Bruce Fields --- include/linux/sunrpc/svc.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/sunrpc/svc.h b/include/linux/sunrpc/svc.h index 43f88bd7b601..73e130a840ce 100644 --- a/include/linux/sunrpc/svc.h +++ b/include/linux/sunrpc/svc.h @@ -499,7 +499,8 @@ unsigned int svc_fill_write_vector(struct svc_rqst *rqstp, struct page **pages, struct kvec *first, size_t total); char *svc_fill_symlink_pathname(struct svc_rqst *rqstp, - struct kvec *first, size_t total); + struct kvec *first, void *p, + size_t total); #define RPC_MAX_ADDRBUFLEN (63U) -- cgit v1.2.3