[RFC PATCH] procd: completely remove tmp-on-zram support

[Rui Salvaterra]

This is the follow-up patch to "procd: don't let the user choose to mount /tmp
on zram". As explained there, this feature is both redundant and more limited
than using a zram swap device, as already provided by the zram-swap package.

Signed-off-by: Rui Salvaterra <rsalvaterra at gmail.com>
---
 CMakeLists.txt |   7 +--
 initd/early.c  |  12 ++---
 initd/init.h   |   7 ---
 initd/zram.c   | 137 -------------------------------------------------
 4 files changed, 5 insertions(+), 158 deletions(-)
 delete mode 100644 initd/zram.c

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 3eb79f9..5f23fb8 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -41,11 +41,6 @@ IF(EARLY_PATH)
   ADD_DEFINITIONS(-DEARLY_PATH="${EARLY_PATH}")
 ENDIF()
 
-IF(ZRAM_TMPFS)
-  ADD_DEFINITIONS(-DZRAM_TMPFS)
-  SET(SOURCES_ZRAM initd/zram.c)
-ENDIF()
-
 add_subdirectory(upgraded)
 
 ADD_EXECUTABLE(procd ${SOURCES})
@@ -61,7 +56,7 @@ IF(DISABLE_INIT)
 ADD_DEFINITIONS(-DDISABLE_INIT)
 ELSE()
 ADD_EXECUTABLE(init initd/init.c initd/early.c initd/preinit.c initd/mkdev.c sysupgrade.c watchdog.c
-	utils/utils.c ${SOURCES_ZRAM})
+	utils/utils.c)
 TARGET_LINK_LIBRARIES(init ${LIBS})
 INSTALL(TARGETS init
 	RUNTIME DESTINATION ${CMAKE_INSTALL_SBINDIR}
diff --git a/initd/early.c b/initd/early.c
index 7b281b2..6ba553f 100644
--- a/initd/early.c
+++ b/initd/early.c
@@ -70,14 +70,10 @@ early_mounts(void)
 	}
 
 	early_console("/dev/console");
-	if (mount_zram_on_tmp()) {
-		mount("tmpfs", "/tmp", "tmpfs", MS_NOSUID | MS_NODEV | MS_NOATIME, "mode=01777");
-		mkdir("/tmp/shm", 01777);
-	} else {
-		mkdir("/tmp/shm", 01777);
-		mount("tmpfs", "/tmp/shm", "tmpfs", MS_NOSUID | MS_NODEV | MS_NOATIME,
-				"mode=01777");
-	}
+
+	mount("tmpfs", "/tmp", "tmpfs", MS_NOSUID | MS_NODEV | MS_NOATIME, "mode=01777");
+	mkdir("/tmp/shm", 01777);
+
 	mkdir("/tmp/run", 0755);
 	mkdir("/tmp/lock", 0755);
 	mkdir("/tmp/state", 0755);
diff --git a/initd/init.h b/initd/init.h
index 123e114..dcf9d30 100644
--- a/initd/init.h
+++ b/initd/init.h
@@ -26,11 +26,4 @@ void preinit(void);
 void early(void);
 int mkdev(const char *progname, int progmode);
 
-#ifdef ZRAM_TMPFS
-int mount_zram_on_tmp(void);
-#else
-static inline int mount_zram_on_tmp(void) {
-	return -ENOSYS;
-}
-#endif
 #endif
diff --git a/initd/zram.c b/initd/zram.c
deleted file mode 100644
index 380fe0e..0000000
--- a/initd/zram.c
+++ /dev/null
@@ -1,137 +0,0 @@
-#include <stdio.h>
-#include <unistd.h>
-#include <stdlib.h>
-#include <string.h>
-#include <errno.h>
-#include <fcntl.h>
-
-#include <sys/utsname.h>
-#include <sys/mount.h>
-#include <sys/types.h>
-#include <sys/wait.h>
-#include <sys/stat.h>
-
-#include "../log.h"
-#include "../container.h"
-
-#include "init.h"
-
-#define KB(x) (x * 1024)
-
-#define ZRAM_MOD_PATH "/lib/modules/%s/zram.ko"
-#define EXT4_MOD_PATH "/lib/modules/%s/ext4.ko"
-
-static long
-proc_meminfo(void)
-{
-	FILE *fp;
-	char line[256];
-	char *key;
-	long val = KB(16);
-
-	fp = fopen("/proc/meminfo", "r");
-	if (fp == NULL) {
-		ERROR("Can't open /proc/meminfo: %m\n");
-		return errno;
-	}
-
-	while (fgets(line, sizeof(line), fp)) {
-		key = strtok(line, ":");
-		if (strcasecmp(key, "MemTotal"))
-			continue;
-		val = atol(strtok(NULL, " kB\n"));
-		break;
-	}
-	fclose(fp);
-
-	if (val > KB(32))
-		val = KB(32);
-
-	return val;
-}
-
-static int
-early_insmod(char *module)
-{
-	pid_t pid = fork();
-	char *modprobe[] = { "/sbin/modprobe", NULL, NULL };
-
-	if (!pid) {
-		char *path;
-		struct utsname ver;
-
-		uname(&ver);
-		path = alloca(strlen(module) + strlen(ver.release) + 1);
-		sprintf(path, module, ver.release);
-		modprobe[1] = path;
-		execvp(modprobe[0], modprobe);
-		ERROR("Can't exec %s: %m\n", modprobe[0]);
-		exit(EXIT_FAILURE);
-	}
-
-	if (pid <= 0) {
-		ERROR("Can't exec %s: %m\n", modprobe[0]);
-		return -1;
-	} else {
-		waitpid(pid, NULL, 0);
-	}
-
-	return 0;
-}
-
-
-int
-mount_zram_on_tmp(void)
-{
-	char *mkfs[] = { "/usr/sbin/mkfs.ext4", "-b", "4096", "-F", "-L", "TEMP", "-m", "0", "/dev/zram0", NULL };
-	FILE *fp;
-	long zramsize;
-	pid_t pid;
-	int ret;
-
-	if (early_insmod(ZRAM_MOD_PATH) || early_insmod(EXT4_MOD_PATH)) {
-		ERROR("failed to insmod zram support\n");
-		return -1;
-	}
-
-	mkdev("*", 0600);
-
-	zramsize = proc_meminfo() / 2;
-	fp = fopen("/sys/block/zram0/disksize", "r+");
-	if (fp == NULL) {
-		ERROR("Can't open /sys/block/zram0/disksize: %m\n");
-		return errno;
-	}
-	fprintf(fp, "%ld", KB(zramsize));
-	fclose(fp);
-
-	pid = fork();
-	if (!pid) {
-		execvp(mkfs[0], mkfs);
-		ERROR("Can't exec %s: %m\n", mkfs[0]);
-		exit(EXIT_FAILURE);
-	} else if (pid <= 0) {
-		ERROR("Can't exec %s: %m\n", mkfs[0]);
-		return -1;
-	} else {
-		waitpid(pid, NULL, 0);
-	}
-
-	if (!is_container()) {
-		ret = mount("/dev/zram0", "/tmp", "ext4", MS_NOSUID | MS_NODEV | MS_NOATIME, "errors=continue,noquota");
-		if (ret < 0) {
-			ERROR("Can't mount /dev/zram0 on /tmp: %m\n");
-			return errno;
-		}
-	}
-
-	LOG("Using up to %ld kB of RAM as ZRAM storage on /mnt\n", zramsize);
-
-	ret = chmod("/tmp", 01777);
-	if (ret < 0) {
-		ERROR("Can't set /tmp mode to 1777: %m\n");
-		return errno;
-	}
-
-	return 0;
-}
-- 
2.27.0