From 978ffef22f6fe6e56b3705921b6458211cb19a9e Mon Sep 17 00:00:00 2001
From: Edward Tomasz Napierala <trasz@FreeBSD.org>
Date: Sat, 18 Jul 2020 10:56:04 +0000
Subject: [PATCH] Add missing SysV IPC stats to linprocfs(4).  Fixes 'ipcs -l',
 and also helps Oracle.

MFC after:	2 weeks
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D25669
---
 sys/compat/linprocfs/linprocfs.c | 68 ++++++++++++++++++++++++++++++++
 1 file changed, 68 insertions(+)

diff --git a/sys/compat/linprocfs/linprocfs.c b/sys/compat/linprocfs/linprocfs.c
index e36914732f8d..2dd9b43ac017 100644
--- a/sys/compat/linprocfs/linprocfs.c
+++ b/sys/compat/linprocfs/linprocfs.c
@@ -66,6 +66,7 @@ __FBSDID("$FreeBSD$");
 #include <sys/resource.h>
 #include <sys/sbuf.h>
 #include <sys/sem.h>
+#include <sys/shm.h>
 #include <sys/smp.h>
 #include <sys/socket.h>
 #include <sys/syscallsubr.h>
@@ -1404,6 +1405,17 @@ linprocfs_doosbuild(PFS_FILL_ARGS)
 	return (0);
 }
 
+/*
+ * Filler function for proc/sys/kernel/msgmax
+ */
+static int
+linprocfs_domsgmax(PFS_FILL_ARGS)
+{
+
+	sbuf_printf(sb, "%d\n", msginfo.msgmax);
+	return (0);
+}
+
 /*
  * Filler function for proc/sys/kernel/msgmni
  */
@@ -1415,6 +1427,17 @@ linprocfs_domsgmni(PFS_FILL_ARGS)
 	return (0);
 }
 
+/*
+ * Filler function for proc/sys/kernel/msgmnb
+ */
+static int
+linprocfs_domsgmnb(PFS_FILL_ARGS)
+{
+
+	sbuf_printf(sb, "%d\n", msginfo.msgmnb);
+	return (0);
+}
+
 /*
  * Filler function for proc/sys/kernel/pid_max
  */
@@ -1438,6 +1461,39 @@ linprocfs_dosem(PFS_FILL_ARGS)
 	return (0);
 }
 
+/*
+ * Filler function for proc/sys/kernel/shmall
+ */
+static int
+linprocfs_doshmall(PFS_FILL_ARGS)
+{
+
+	sbuf_printf(sb, "%lu\n", shminfo.shmall);
+	return (0);
+}
+
+/*
+ * Filler function for proc/sys/kernel/shmmax
+ */
+static int
+linprocfs_doshmmax(PFS_FILL_ARGS)
+{
+
+	sbuf_printf(sb, "%lu\n", shminfo.shmmax);
+	return (0);
+}
+
+/*
+ * Filler function for proc/sys/kernel/shmmni
+ */
+static int
+linprocfs_doshmmni(PFS_FILL_ARGS)
+{
+
+	sbuf_printf(sb, "%lu\n", shminfo.shmmni);
+	return (0);
+}
+
 /*
  * Filler function for proc/sys/kernel/tainted
  */
@@ -1837,6 +1893,7 @@ linprocfs_init(PFS_INIT_ARGS)
 
 	/* /proc/sys/... */
 	sys = pfs_create_dir(root, "sys", NULL, NULL, NULL, 0);
+
 	/* /proc/sys/kernel/... */
 	dir = pfs_create_dir(sys, "kernel", NULL, NULL, NULL, 0);
 	pfs_create_file(dir, "osrelease", &linprocfs_doosrelease,
@@ -1845,12 +1902,22 @@ linprocfs_init(PFS_INIT_ARGS)
 	    NULL, NULL, NULL, PFS_RD);
 	pfs_create_file(dir, "version", &linprocfs_doosbuild,
 	    NULL, NULL, NULL, PFS_RD);
+	pfs_create_file(dir, "msgmax", &linprocfs_domsgmax,
+	    NULL, NULL, NULL, PFS_RD);
 	pfs_create_file(dir, "msgmni", &linprocfs_domsgmni,
 	    NULL, NULL, NULL, PFS_RD);
+	pfs_create_file(dir, "msgmnb", &linprocfs_domsgmnb,
+	    NULL, NULL, NULL, PFS_RD);
 	pfs_create_file(dir, "pid_max", &linprocfs_dopid_max,
 	    NULL, NULL, NULL, PFS_RD);
 	pfs_create_file(dir, "sem", &linprocfs_dosem,
 	    NULL, NULL, NULL, PFS_RD);
+	pfs_create_file(dir, "shmall", &linprocfs_doshmall,
+	    NULL, NULL, NULL, PFS_RD);
+	pfs_create_file(dir, "shmmax", &linprocfs_doshmmax,
+	    NULL, NULL, NULL, PFS_RD);
+	pfs_create_file(dir, "shmmni", &linprocfs_doshmmni,
+	    NULL, NULL, NULL, PFS_RD);
 	pfs_create_file(dir, "tainted", &linprocfs_dotainted,
 	    NULL, NULL, NULL, PFS_RD);
 
@@ -1887,3 +1954,4 @@ MODULE_DEPEND(linprocfs, linux, 1, 1, 1);
 MODULE_DEPEND(linprocfs, procfs, 1, 1, 1);
 MODULE_DEPEND(linprocfs, sysvmsg, 1, 1, 1);
 MODULE_DEPEND(linprocfs, sysvsem, 1, 1, 1);
+MODULE_DEPEND(linprocfs, sysvshm, 1, 1, 1);