@splice_desc.total_len is 32 bit(unsigned int) which is used to store the size passed from userspace which is 64 bit(size_t) so that the size is unexpectedly truncated
That causes vmsplice can not work if the size passed from userspace is >= 4G, for example, we noticed in vmsplice, splice-reader does not do anything and splice-writer is waiting for available buffer forever if the size is 4G Fix it by extending @splice_desc.total_len to 64 bits as well Signed-off-by: Xiao Guangrong <[email protected]> --- include/linux/splice.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/include/linux/splice.h b/include/linux/splice.h index 74575cb..1e85396 100644 --- a/include/linux/splice.h +++ b/include/linux/splice.h @@ -24,7 +24,8 @@ * Passed to the actors */ struct splice_desc { - unsigned int len, total_len; /* current and remaining length */ + size_t total_len; /* remaining length */ + unsigned int len; /* current length */ unsigned int flags; /* splice flags */ /* * actor() private data -- 1.8.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
