9 files changed, 159 insertions, 76 deletions

diff --git a/arch/um/os-Linux/Makefile b/arch/um/os-Linux/Makefile
index 1659386b42bb..f4bfc4c7ccac 100644
--- a/arch/um/os-Linux/Makefile
+++ b/arch/um/os-Linux/Makefile
@@ -4,7 +4,7 @@
 #
 
 obj-y = aio.o elf_aux.o file.o helper.o irq.o main.o mem.o process.o sigio.o \
-        signal.o start_up.o time.o trap.o tt.o tty.o uaccess.o umid.o \
+        signal.o start_up.o time.o trap.o tt.o tty.o uaccess.o umid.o tls.o \
         user_syms.o util.o drivers/ sys-$(SUBARCH)/
 
 obj-$(CONFIG_MODE_SKAS) += skas/
@@ -12,12 +12,9 @@ obj-$(CONFIG_TTY_LOG) += tty_log.o
 user-objs-$(CONFIG_TTY_LOG) += tty_log.o
 
 USER_OBJS := $(user-objs-y) aio.o elf_aux.o file.o helper.o irq.o main.o mem.o \
-        process.o sigio.o signal.o start_up.o time.o trap.o tt.o tty.o \
+        process.o sigio.o signal.o start_up.o time.o trap.o tt.o tty.o tls.o \
         uaccess.o umid.o util.o
 
-elf_aux.o: $(ARCH_DIR)/kernel-offsets.h
-CFLAGS_elf_aux.o += -I$(objtree)/arch/um
-
 CFLAGS_user_syms.o += -DSUBARCH_$(SUBARCH)
 
 HAVE_AIO_ABI := $(shell [ -r /usr/include/linux/aio_abi.h ] && \
diff --git a/arch/um/os-Linux/drivers/ethertap_kern.c b/arch/um/os-Linux/drivers/ethertap_kern.c
index 6ae4b19d9f50..768606bec233 100644
--- a/arch/um/os-Linux/drivers/ethertap_kern.c
+++ b/arch/um/os-Linux/drivers/ethertap_kern.c
@@ -102,18 +102,7 @@ static struct transport ethertap_transport = {
 static int register_ethertap(void)
 {
         register_transport(&ethertap_transport);
-        return(1);
+        return 0;
 }
 
 __initcall(register_ethertap);
-
-/*
- * Overrides for Emacs so that we follow Linus's tabbing style.
- * Emacs will notice this stuff at the end of the file and automatically
- * adjust the settings for this buffer only.  This must remain at the end
- * of the file.
- * ---------------------------------------------------------------------------
- * Local variables:
- * c-file-style: "linux"
- * End:
- */
diff --git a/arch/um/os-Linux/drivers/tuntap_kern.c b/arch/um/os-Linux/drivers/tuntap_kern.c
index 4202b9ebad4c..190009a6f89c 100644
--- a/arch/um/os-Linux/drivers/tuntap_kern.c
+++ b/arch/um/os-Linux/drivers/tuntap_kern.c
@@ -87,18 +87,7 @@ static struct transport tuntap_transport = {
 static int register_tuntap(void)
 {
         register_transport(&tuntap_transport);
-        return(1);
+        return 0;
 }
 
 __initcall(register_tuntap);
-
-/*
- * Overrides for Emacs so that we follow Linus's tabbing style.
- * Emacs will notice this stuff at the end of the file and automatically
- * adjust the settings for this buffer only.  This must remain at the end
- * of the file.
- * ---------------------------------------------------------------------------
- * Local variables:
- * c-file-style: "linux"
- * End:
- */
diff --git a/arch/um/os-Linux/mem.c b/arch/um/os-Linux/mem.c
index 9d7d69a523bb..6ab372da9657 100644
--- a/arch/um/os-Linux/mem.c
+++ b/arch/um/os-Linux/mem.c
@@ -121,36 +121,11 @@ int create_tmp_file(unsigned long long len)
         return(fd);
 }
 
-static int create_anon_file(unsigned long long len)
-{
-        void *addr;
-        int fd;
-
-        fd = open("/dev/anon", O_RDWR);
-        if(fd < 0) {
-                perror("opening /dev/anon");
-                exit(1);
-        }
-
-        addr = mmap(NULL, len, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
-        if(addr == MAP_FAILED){
-                perror("mapping physmem file");
-                exit(1);
-        }
-        munmap(addr, len);
-
-        return(fd);
-}
-
-extern int have_devanon;
-
 int create_mem_file(unsigned long long len)
 {
         int err, fd;
 
-        if(have_devanon)
-                fd = create_anon_file(len);
-        else fd = create_tmp_file(len);
+        fd = create_tmp_file(len);
 
         err = os_set_exec_close(fd, 1);
         if(err < 0){
diff --git a/arch/um/os-Linux/process.c b/arch/um/os-Linux/process.c
index d261888f39c4..8176b0b52047 100644
--- a/arch/um/os-Linux/process.c
+++ b/arch/um/os-Linux/process.c
@@ -11,6 +11,7 @@
 #include <linux/unistd.h>
 #include <sys/mman.h>
 #include <sys/wait.h>
+#include <sys/mman.h>
 #include "ptrace_user.h"
 #include "os.h"
 #include "user.h"
@@ -20,6 +21,7 @@
 #include "kern_util.h"
 #include "longjmp.h"
 #include "skas_ptrace.h"
+#include "kern_constants.h"
 
 #define ARBITRARY_ADDR -1
 #define FAILURE_PID    -1
@@ -187,6 +189,48 @@ int os_unmap_memory(void *addr, int len)
         return(0);
 }
 
+#ifndef MADV_REMOVE
+#define MADV_REMOVE     0x5             /* remove these pages & resources */
+#endif
+
+int os_drop_memory(void *addr, int length)
+{
+        int err;
+
+        err = madvise(addr, length, MADV_REMOVE);
+        if(err < 0)
+                err = -errno;
+        return err;
+}
+
+int can_drop_memory(void)
+{
+        void *addr;
+        int fd;
+
+        printk("Checking host MADV_REMOVE support...");
+        fd = create_mem_file(UM_KERN_PAGE_SIZE);
+        if(fd < 0){
+                printk("Creating test memory file failed, err = %d\n", -fd);
+                return 0;
+        }
+
+        addr = mmap64(NULL, UM_KERN_PAGE_SIZE, PROT_READ | PROT_WRITE,
+                      MAP_PRIVATE, fd, 0);
+        if(addr == MAP_FAILED){
+                printk("Mapping test memory file failed, err = %d\n", -errno);
+                return 0;
+        }
+
+        if(madvise(addr, UM_KERN_PAGE_SIZE, MADV_REMOVE) != 0){
+                printk("MADV_REMOVE failed, err = %d\n", -errno);
+                return 0;
+        }
+
+        printk("OK\n");
+        return 1;
+}
+
 void init_new_thread_stack(void *sig_stack, void (*usr1_handler)(int))
 {
         int flags = 0, pages;
diff --git a/arch/um/os-Linux/start_up.c b/arch/um/os-Linux/start_up.c
index 32753131f8d8..387e26af301a 100644
--- a/arch/um/os-Linux/start_up.c
+++ b/arch/um/os-Linux/start_up.c
@@ -470,25 +470,6 @@ int can_do_skas(void)
 }
 #endif
 
-int have_devanon = 0;
-
-/* Runs on boot kernel stack - already safe to use printk. */
-
-void check_devanon(void)
-{
-        int fd;
-
-        printk("Checking for /dev/anon on the host...");
-        fd = open("/dev/anon", O_RDWR);
-        if(fd < 0){
-                printk("Not available (open failed with errno %d)\n", errno);
-                return;
-        }
-
-        printk("OK\n");
-        have_devanon = 1;
-}
-
 int __init parse_iomem(char *str, int *add)
 {
         struct iomem_region *new;
@@ -664,6 +645,5 @@ void os_check_bugs(void)
 {
         check_ptrace();
         check_sigio();
-        check_devanon();
 }
 
diff --git a/arch/um/os-Linux/sys-i386/Makefile b/arch/um/os-Linux/sys-i386/Makefile
index 340ef26f5944..b3213613c41c 100644
--- a/arch/um/os-Linux/sys-i386/Makefile
+++ b/arch/um/os-Linux/sys-i386/Makefile
@@ -3,7 +3,7 @@
 # Licensed under the GPL
 #
 
-obj-$(CONFIG_MODE_SKAS) = registers.o
+obj-$(CONFIG_MODE_SKAS) = registers.o tls.o
 
 USER_OBJS := $(obj-y)
 
diff --git a/arch/um/os-Linux/sys-i386/tls.c b/arch/um/os-Linux/sys-i386/tls.c
new file mode 100644
index 000000000000..ba21f0e04a2f
--- /dev/null
+++ b/arch/um/os-Linux/sys-i386/tls.c
@@ -0,0 +1,33 @@
+#include <linux/unistd.h>
+#include "sysdep/tls.h"
+#include "user_util.h"
+
+static _syscall1(int, get_thread_area, user_desc_t *, u_info);
+
+/* Checks whether host supports TLS, and sets *tls_min according to the value
+ * valid on the host.
+ * i386 host have it == 6; x86_64 host have it == 12, for i386 emulation. */
+void check_host_supports_tls(int *supports_tls, int *tls_min) {
+        /* Values for x86 and x86_64.*/
+        int val[] = {GDT_ENTRY_TLS_MIN_I386, GDT_ENTRY_TLS_MIN_X86_64};
+        int i;
+
+        for (i = 0; i < ARRAY_SIZE(val); i++) {
+                user_desc_t info;
+                info.entry_number = val[i];
+
+                if (get_thread_area(&info) == 0) {
+                        *tls_min = val[i];
+                        *supports_tls = 1;
+                        return;
+                } else {
+                        if (errno == EINVAL)
+                                continue;
+                        else if (errno == ENOSYS)
+                                *supports_tls = 0;
+                                return;
+                }
+        }
+
+        *supports_tls = 0;
+}
diff --git a/arch/um/os-Linux/tls.c b/arch/um/os-Linux/tls.c
new file mode 100644
index 000000000000..9cb09a45546b
--- /dev/null
+++ b/arch/um/os-Linux/tls.c
@@ -0,0 +1,76 @@
+#include <errno.h>
+#include <sys/ptrace.h>
+#include <asm/ldt.h>
+#include "sysdep/tls.h"
+#include "uml-config.h"
+
+/* TLS support - we basically rely on the host's one.*/
+
+/* In TT mode, this should be called only by the tracing thread, and makes sense
+ * only for PTRACE_SET_THREAD_AREA. In SKAS mode, it's used normally.
+ *
+ */
+
+#ifndef PTRACE_GET_THREAD_AREA
+#define PTRACE_GET_THREAD_AREA 25
+#endif
+
+#ifndef PTRACE_SET_THREAD_AREA
+#define PTRACE_SET_THREAD_AREA 26
+#endif
+
+int os_set_thread_area(user_desc_t *info, int pid)
+{
+        int ret;
+
+        ret = ptrace(PTRACE_SET_THREAD_AREA, pid, info->entry_number,
+                     (unsigned long) info);
+        if (ret < 0)
+                ret = -errno;
+        return ret;
+}
+
+#ifdef UML_CONFIG_MODE_SKAS
+
+int os_get_thread_area(user_desc_t *info, int pid)
+{
+        int ret;
+
+        ret = ptrace(PTRACE_GET_THREAD_AREA, pid, info->entry_number,
+                     (unsigned long) info);
+        if (ret < 0)
+                ret = -errno;
+        return ret;
+}
+
+#endif
+
+#ifdef UML_CONFIG_MODE_TT
+#include "linux/unistd.h"
+
+static _syscall1(int, get_thread_area, user_desc_t *, u_info);
+static _syscall1(int, set_thread_area, user_desc_t *, u_info);
+
+int do_set_thread_area_tt(user_desc_t *info)
+{
+        int ret;
+
+        ret = set_thread_area(info);
+        if (ret < 0) {
+                ret = -errno;
+        }
+        return ret;
+}
+
+int do_get_thread_area_tt(user_desc_t *info)
+{
+        int ret;
+
+        ret = get_thread_area(info);
+        if (ret < 0) {
+                ret = -errno;
+        }
+        return ret;
+}
+
+#endif /* UML_CONFIG_MODE_TT */