lguest: per-cpu run guest

This patch makes the run_guest() routine use the lg_cpu struct.
This is required since in a smp guest environment, there's no
more the notion of "running the guest", but rather, it is "running the vcpu"

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

diff --git a/drivers/lguest/core.c b/drivers/lguest/core.c
index c1069bceba11dde196f02e75f691e3ed873565ba..75b38f2c778a752b3d2c4474fd775788afd4306b 100644 (file)
--- a/drivers/lguest/core.c
+++ b/drivers/lguest/core.c
@@ -174,8 +174,10 @@ void __lgwrite(struct lguest *lg, unsigned long addr, const void *b,
 /*H:030 Let's jump straight to the the main loop which runs the Guest.
  * Remember, this is called by the Launcher reading /dev/lguest, and we keep
  * going around and around until something interesting happens. */
-int run_guest(struct lguest *lg, unsigned long __user *user)
+int run_guest(struct lg_cpu *cpu, unsigned long __user *user)
 {
+       struct lguest *lg = cpu->lg;
+
        /* We stop running once the Guest is dead. */
        while (!lg->dead) {
                /* First we run any hypercalls the Guest wants done. */
@@ -226,7 +228,7 @@ int run_guest(struct lguest *lg, unsigned long __user *user)
                local_irq_disable();
 
                /* Actually run the Guest until something happens. */
-               lguest_arch_run_guest(lg);
+               lguest_arch_run_guest(cpu);
 
                /* Now we're ready to be interrupted or moved to other CPUs */
                local_irq_enable();

diff --git a/drivers/lguest/lg.h b/drivers/lguest/lg.h
index 5f73ddff0e3d7ef2c0a068e8093180c18a09c2a3..bfca2716ad114d8413451519df05c9497cd01f7d 100644 (file)
--- a/drivers/lguest/lg.h
+++ b/drivers/lguest/lg.h
@@ -126,7 +126,7 @@ void __lgwrite(struct lguest *, unsigned long, const void *, unsigned);
        } while(0)
 /* (end of memory access helper routines) :*/
 
-int run_guest(struct lguest *lg, unsigned long __user *user);
+int run_guest(struct lg_cpu *cpu, unsigned long __user *user);
 
 /* Helper macros to obtain the first 12 or the last 20 bits, this is only the
  * first step in the migration to the kernel types.  pte_pfn is already defined
@@ -177,7 +177,7 @@ void page_table_guest_data_init(struct lguest *lg);
 /* <arch>/core.c: */
 void lguest_arch_host_init(void);
 void lguest_arch_host_fini(void);
-void lguest_arch_run_guest(struct lguest *lg);
+void lguest_arch_run_guest(struct lg_cpu *cpu);
 void lguest_arch_handle_trap(struct lguest *lg);
 int lguest_arch_init_hypercalls(struct lguest *lg);
 int lguest_arch_do_hcall(struct lguest *lg, struct hcall_args *args);

diff --git a/drivers/lguest/lguest_user.c b/drivers/lguest/lguest_user.c
index c4bfe5a2b6b7d320985dab2f9e99de217313ed2b..9f0a4432994709288f3ef4fb6091cc22c6e4f130 100644 (file)
--- a/drivers/lguest/lguest_user.c
+++ b/drivers/lguest/lguest_user.c
@@ -55,11 +55,19 @@ static int user_send_irq(struct lguest *lg, const unsigned long __user *input)
 static ssize_t read(struct file *file, char __user *user, size_t size,loff_t*o)
 {
        struct lguest *lg = file->private_data;
+       struct lg_cpu *cpu;
+       unsigned int cpu_id = *o;
 
        /* You must write LHREQ_INITIALIZE first! */
        if (!lg)
                return -EINVAL;
 
+       /* Watch out for arbitrary vcpu indexes! */
+       if (cpu_id >= lg->nr_cpus)
+               return -EINVAL;
+
+       cpu = &lg->cpus[cpu_id];
+
        /* If you're not the task which owns the Guest, go away. */
        if (current != lg->tsk)
                return -EPERM;
@@ -85,7 +93,7 @@ static ssize_t read(struct file *file, char __user *user, size_t size,loff_t*o)
                lg->pending_notify = 0;
 
        /* Run the Guest until something interesting happens. */
-       return run_guest(lg, (unsigned long __user *)user);
+       return run_guest(cpu, (unsigned long __user *)user);
 }
 
 static int lg_cpu_start(struct lg_cpu *cpu, unsigned id, unsigned long start_ip)
@@ -147,7 +155,7 @@ static int initialize(struct file *file, const unsigned long __user *input)
        lg->pfn_limit = args[1];
 
        /* This is the first cpu */
-       err = cpu_start(&lg->cpus[0], 0, args[3]);
+       err = lg_cpu_start(&lg->cpus[0], 0, args[3]);
        if (err)
                goto release_guest;
 

diff --git a/drivers/lguest/x86/core.c b/drivers/lguest/x86/core.c
index 96d0fd07c57d5702fe9666a587df05a2ced29c51..3d2131e169fdc3f41eb32ef8aa97848b524d7074 100644 (file)
--- a/drivers/lguest/x86/core.c
+++ b/drivers/lguest/x86/core.c
@@ -73,8 +73,9 @@ static DEFINE_PER_CPU(struct lguest *, last_guest);
  * since it last ran.  We saw this set in interrupts_and_traps.c and
  * segments.c.
  */
-static void copy_in_guest_info(struct lguest *lg, struct lguest_pages *pages)
+static void copy_in_guest_info(struct lg_cpu *cpu, struct lguest_pages *pages)
 {
+       struct lguest *lg = cpu->lg;
        /* Copying all this data can be quite expensive.  We usually run the
         * same Guest we ran last time (and that Guest hasn't run anywhere else
         * meanwhile).  If that's not the case, we pretend everything in the
@@ -113,14 +114,15 @@ static void copy_in_guest_info(struct lguest *lg, struct lguest_pages *pages)
 }
 
 /* Finally: the code to actually call into the Switcher to run the Guest. */
-static void run_guest_once(struct lguest *lg, struct lguest_pages *pages)
+static void run_guest_once(struct lg_cpu *cpu, struct lguest_pages *pages)
 {
        /* This is a dummy value we need for GCC's sake. */
        unsigned int clobber;
+       struct lguest *lg = cpu->lg;
 
        /* Copy the guest-specific information into this CPU's "struct
         * lguest_pages". */
-       copy_in_guest_info(lg, pages);
+       copy_in_guest_info(cpu, pages);
 
        /* Set the trap number to 256 (impossible value).  If we fault while
         * switching to the Guest (bad segment registers or bug), this will
@@ -161,8 +163,10 @@ static void run_guest_once(struct lguest *lg, struct lguest_pages *pages)
 
 /*H:040 This is the i386-specific code to setup and run the Guest.  Interrupts
  * are disabled: we own the CPU. */
-void lguest_arch_run_guest(struct lguest *lg)
+void lguest_arch_run_guest(struct lg_cpu *cpu)
 {
+       struct lguest *lg = cpu->lg;
+
        /* Remember the awfully-named TS bit?  If the Guest has asked to set it
         * we set it now, so we can trap and pass that trap to the Guest if it
         * uses the FPU. */
@@ -180,7 +184,7 @@ void lguest_arch_run_guest(struct lguest *lg)
        /* Now we actually run the Guest.  It will return when something
         * interesting happens, and we can examine its registers to see what it
         * was doing. */
-       run_guest_once(lg, lguest_pages(raw_smp_processor_id()));
+       run_guest_once(cpu, lguest_pages(raw_smp_processor_id()));
 
        /* Note that the "regs" pointer contains two extra entries which are
         * not really registers: a trap number which says what interrupt or