From 2384981b61d1fba364c8be763b40432de49f4fa4 Mon Sep 17 00:00:00 2001 From: Conrad Meyer Date: Fri, 26 Oct 2018 20:07:46 +0000 Subject: poll: Unify userspace pollfd pointer name Some of the poll code used 'fds' and some used 'ufds' to refer to the uap->fds userspace pointer that was passed around to subroutines. Some of the poll code used 'fds' to refer to the kernel memory pollfd arrays, which seemed unnecessarily confusing. Unify on 'ufds' to refer to the userspace pollfd array. Additionally, 'bits' is not an accurate description of the kernel pollfd array in kern_poll, so rename that to 'kfds'. Finally, clean up some logic with mallocarray() and nitems(). No functional change. Reviewed by: markj Differential Revision: https://reviews.freebsd.org/D17670 --- sys/kern/sys_generic.c | 24 +++++++++++------------- 1 file changed, 11 insertions(+), 13 deletions(-) (limited to 'sys/kern/sys_generic.c') diff --git a/sys/kern/sys_generic.c b/sys/kern/sys_generic.c index 455220c36752..0e8e173654c5 100644 --- a/sys/kern/sys_generic.c +++ b/sys/kern/sys_generic.c @@ -1304,16 +1304,15 @@ sys_poll(struct thread *td, struct poll_args *uap) } int -kern_poll(struct thread *td, struct pollfd *fds, u_int nfds, +kern_poll(struct thread *td, struct pollfd *ufds, u_int nfds, struct timespec *tsp, sigset_t *uset) { - struct pollfd *bits; - struct pollfd smallbits[32]; + struct pollfd *kfds; + struct pollfd stackfds[32]; sbintime_t sbt, precision, tmp; time_t over; struct timespec ts; int error; - size_t ni; precision = 0; if (tsp != NULL) { @@ -1342,12 +1341,11 @@ kern_poll(struct thread *td, struct pollfd *fds, u_int nfds, if (nfds > maxfilesperproc && nfds > FD_SETSIZE) return (EINVAL); - ni = nfds * sizeof(struct pollfd); - if (ni > sizeof(smallbits)) - bits = malloc(ni, M_TEMP, M_WAITOK); + if (nfds > nitems(stackfds)) + kfds = mallocarray(nfds, sizeof(*kfds), M_TEMP, M_WAITOK); else - bits = smallbits; - error = copyin(fds, bits, ni); + kfds = stackfds; + error = copyin(ufds, kfds, nfds * sizeof(*kfds)); if (error) goto done; @@ -1370,7 +1368,7 @@ kern_poll(struct thread *td, struct pollfd *fds, u_int nfds, seltdinit(td); /* Iterate until the timeout expires or descriptors become ready. */ for (;;) { - error = pollscan(td, bits, nfds); + error = pollscan(td, kfds, nfds); if (error || td->td_retval[0] != 0) break; error = seltdwait(td, sbt, precision); @@ -1389,13 +1387,13 @@ done: if (error == EWOULDBLOCK) error = 0; if (error == 0) { - error = pollout(td, bits, fds, nfds); + error = pollout(td, kfds, ufds, nfds); if (error) goto out; } out: - if (ni > sizeof(smallbits)) - free(bits, M_TEMP); + if (nfds > nitems(stackfds)) + free(kfds, M_TEMP); return (error); } -- cgit v1.2.3