The branch main has been updated by brooks:
URL:
https://cgit.FreeBSD.org/src/commit/?id=c3207e2d2554c8e36f9cf5950f8cd52a19fedfd5
commit c3207e2d2554c8e36f9cf5950f8cd52a19fedfd5
Author: Brooks Davis <bro...@freebsd.org>
AuthorDate: 2023-11-27 17:06:33 +0000
Commit: Brooks Davis <bro...@freebsd.org>
CommitDate: 2023-11-28 17:09:27 +0000
memfd_create: move implementation to libc/gen
Due to memfd_create(3)'s construction of a path to pass to shm_open2(2),
it has a much larger than typical dependency footprint for a system
call wrapper (the list currently includes calloc, memset, sprintf, and
strlen). As such, split it off into its own file under libc/gen to
lighten libc/sys's dependency list.
Reviewed by: kevans, imp, emaste
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D42709
---
lib/libc/gen/Makefile.inc | 1 +
lib/libc/gen/Symbol.map | 1 +
lib/libc/gen/memfd_create.c | 131 ++++++++++++++++++++++++++++++++++++++++++++
lib/libc/sys/Symbol.map | 1 -
lib/libc/sys/shm_open.c | 93 -------------------------------
5 files changed, 133 insertions(+), 94 deletions(-)
diff --git a/lib/libc/gen/Makefile.inc b/lib/libc/gen/Makefile.inc
index 5cb471fe4672..f657bd949cb7 100644
--- a/lib/libc/gen/Makefile.inc
+++ b/lib/libc/gen/Makefile.inc
@@ -101,6 +101,7 @@ SRCS+= __getosreldate.c \
lockf.c \
lrand48.c \
memalign.c \
+ memfd_create.c \
mrand48.c \
nftw.c \
nftw-compat11.c \
diff --git a/lib/libc/gen/Symbol.map b/lib/libc/gen/Symbol.map
index 559c0252c338..b68d63b279f3 100644
--- a/lib/libc/gen/Symbol.map
+++ b/lib/libc/gen/Symbol.map
@@ -433,6 +433,7 @@ FBSD_1.6 {
eventfd_write;
getlogin_r;
memalign;
+ memfd_create;
pthread_getname_np;
scandir_b;
sigandset;
diff --git a/lib/libc/gen/memfd_create.c b/lib/libc/gen/memfd_create.c
new file mode 100644
index 000000000000..b26d638656a4
--- /dev/null
+++ b/lib/libc/gen/memfd_create.c
@@ -0,0 +1,131 @@
+/*
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2019 Kyle Evans <kev...@freebsd.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice(s), this list of conditions and the following disclaimer as
+ * the first lines of this file unmodified other than the possible
+ * addition of one or more copyright notices.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice(s), this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+ * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
+ * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
+ * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/param.h>
+#include <sys/filio.h>
+#include <sys/mman.h>
+
+#include <errno.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "libc_private.h"
+
+#define MEMFD_NAME_PREFIX "memfd:"
+
+/*
+ * The path argument is passed to the kernel, but the kernel doesn't currently
+ * do anything with it. Linux exposes it in linprocfs for debugging purposes
+ * only, but our kernel currently will not do the same.
+ */
+int
+memfd_create(const char *name, unsigned int flags)
+{
+ char memfd_name[NAME_MAX + 1];
+ size_t namelen, *pgs, pgsize;
+ struct shm_largepage_conf slc;
+ int error, fd, npgs, oflags, pgidx, saved_errno, shmflags;
+
+ if (name == NULL) {
+ errno = EBADF;
+ return (-1);
+ }
+ namelen = strlen(name);
+ if (namelen + sizeof(MEMFD_NAME_PREFIX) - 1 > NAME_MAX) {
+ errno = EINVAL;
+ return (-1);
+ }
+ if ((flags & ~(MFD_CLOEXEC | MFD_ALLOW_SEALING | MFD_HUGETLB |
+ MFD_HUGE_MASK)) != 0) {
+ errno = EINVAL;
+ return (-1);
+ }
+ /* Size specified but no HUGETLB. */
+ if ((flags & MFD_HUGE_MASK) != 0 && (flags & MFD_HUGETLB) == 0) {
+ errno = EINVAL;
+ return (-1);
+ }
+
+ /* We've already validated that we're sufficiently sized. */
+ snprintf(memfd_name, NAME_MAX + 1, "%s%s", MEMFD_NAME_PREFIX, name);
+ oflags = O_RDWR;
+ shmflags = 0;
+ if ((flags & MFD_CLOEXEC) != 0)
+ oflags |= O_CLOEXEC;
+ if ((flags & MFD_ALLOW_SEALING) != 0)
+ shmflags |= SHM_ALLOW_SEALING;
+ if ((flags & MFD_HUGETLB) != 0)
+ shmflags |= SHM_LARGEPAGE;
+ else
+ shmflags |= SHM_GROW_ON_WRITE;
+ fd = __sys_shm_open2(SHM_ANON, oflags, 0, shmflags, memfd_name);
+ if (fd == -1 || (flags & MFD_HUGETLB) == 0)
+ return (fd);
+
+ pgs = NULL;
+ npgs = getpagesizes(NULL, 0);
+ if (npgs == -1)
+ goto clean;
+ pgs = calloc(npgs, sizeof(size_t));
+ if (pgs == NULL)
+ goto clean;
+ error = getpagesizes(pgs, npgs);
+ if (error == -1)
+ goto clean;
+ pgsize = (size_t)1 << ((flags & MFD_HUGE_MASK) >> MFD_HUGE_SHIFT);
+ for (pgidx = 0; pgidx < npgs; pgidx++) {
+ if (pgsize == pgs[pgidx])
+ break;
+ }
+ if (pgidx == npgs) {
+ errno = EOPNOTSUPP;
+ goto clean;
+ }
+ free(pgs);
+ pgs = NULL;
+
+ memset(&slc, 0, sizeof(slc));
+ slc.psind = pgidx;
+ slc.alloc_policy = SHM_LARGEPAGE_ALLOC_DEFAULT;
+ error = ioctl(fd, FIOSSHMLPGCNF, &slc);
+ if (error == -1)
+ goto clean;
+ return (fd);
+
+clean:
+ saved_errno = errno;
+ close(fd);
+ free(pgs);
+ errno = saved_errno;
+ return (-1);
+}
diff --git a/lib/libc/sys/Symbol.map b/lib/libc/sys/Symbol.map
index b59ec1858ffd..f17aae279b8d 100644
--- a/lib/libc/sys/Symbol.map
+++ b/lib/libc/sys/Symbol.map
@@ -409,7 +409,6 @@ FBSD_1.6 {
fhreadlink;
getfhat;
funlinkat;
- memfd_create;
shm_create_largepage;
shm_rename;
};
diff --git a/lib/libc/sys/shm_open.c b/lib/libc/sys/shm_open.c
index b2c1532133bf..eb3022c857b1 100644
--- a/lib/libc/sys/shm_open.c
+++ b/lib/libc/sys/shm_open.c
@@ -34,9 +34,6 @@
#include <errno.h>
#include <fcntl.h>
-#include <limits.h>
-#include <stdlib.h>
-#include <stdio.h>
#include <string.h>
#include <unistd.h>
@@ -45,12 +42,9 @@
__weak_reference(shm_open, _shm_open);
__weak_reference(shm_open, __sys_shm_open);
-#define MEMFD_NAME_PREFIX "memfd:"
-
int
shm_open(const char *path, int flags, mode_t mode)
{
-
return (__sys_shm_open2(path, flags | O_CLOEXEC, mode, 0, NULL));
}
@@ -77,90 +71,3 @@ shm_create_largepage(const char *path, int flags, int psind,
int alloc_policy,
}
return (fd);
}
-
-/*
- * The path argument is passed to the kernel, but the kernel doesn't currently
- * do anything with it. Linux exposes it in linprocfs for debugging purposes
- * only, but our kernel currently will not do the same.
- */
-int
-memfd_create(const char *name, unsigned int flags)
-{
- char memfd_name[NAME_MAX + 1];
- size_t namelen, *pgs, pgsize;
- struct shm_largepage_conf slc;
- int error, fd, npgs, oflags, pgidx, saved_errno, shmflags;
-
- if (name == NULL) {
- errno = EBADF;
- return (-1);
- }
- namelen = strlen(name);
- if (namelen + sizeof(MEMFD_NAME_PREFIX) - 1 > NAME_MAX) {
- errno = EINVAL;
- return (-1);
- }
- if ((flags & ~(MFD_CLOEXEC | MFD_ALLOW_SEALING | MFD_HUGETLB |
- MFD_HUGE_MASK)) != 0) {
- errno = EINVAL;
- return (-1);
- }
- /* Size specified but no HUGETLB. */
- if ((flags & MFD_HUGE_MASK) != 0 && (flags & MFD_HUGETLB) == 0) {
- errno = EINVAL;
- return (-1);
- }
-
- /* We've already validated that we're sufficiently sized. */
- snprintf(memfd_name, NAME_MAX + 1, "%s%s", MEMFD_NAME_PREFIX, name);
- oflags = O_RDWR;
- shmflags = 0;
- if ((flags & MFD_CLOEXEC) != 0)
- oflags |= O_CLOEXEC;
- if ((flags & MFD_ALLOW_SEALING) != 0)
- shmflags |= SHM_ALLOW_SEALING;
- if ((flags & MFD_HUGETLB) != 0)
- shmflags |= SHM_LARGEPAGE;
- else
- shmflags |= SHM_GROW_ON_WRITE;
- fd = __sys_shm_open2(SHM_ANON, oflags, 0, shmflags, memfd_name);
- if (fd == -1 || (flags & MFD_HUGETLB) == 0)
- return (fd);
-
- pgs = NULL;
- npgs = getpagesizes(NULL, 0);
- if (npgs == -1)
- goto clean;
- pgs = calloc(npgs, sizeof(size_t));
- if (pgs == NULL)
- goto clean;
- error = getpagesizes(pgs, npgs);
- if (error == -1)
- goto clean;
- pgsize = (size_t)1 << ((flags & MFD_HUGE_MASK) >> MFD_HUGE_SHIFT);
- for (pgidx = 0; pgidx < npgs; pgidx++) {
- if (pgsize == pgs[pgidx])
- break;
- }
- if (pgidx == npgs) {
- errno = EOPNOTSUPP;
- goto clean;
- }
- free(pgs);
- pgs = NULL;
-
- memset(&slc, 0, sizeof(slc));
- slc.psind = pgidx;
- slc.alloc_policy = SHM_LARGEPAGE_ALLOC_DEFAULT;
- error = ioctl(fd, FIOSSHMLPGCNF, &slc);
- if (error == -1)
- goto clean;
- return (fd);
-
-clean:
- saved_errno = errno;
- close(fd);
- free(pgs);
- errno = saved_errno;
- return (-1);
-}
