Remove fixed limit on number of guests, and lguests array.

Back when we had all the Guest state in the switcher, we had a fixed
array of them.  This is no longer necessary.

If we switch the network code to using random_ether_addr (46 bits is
enough to avoid clashes), we can get rid of the concept of "guest id"
altogether.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

1 files changed, 6 insertions, 11 deletions

diff --git a/drivers/lguest/lguest_user.c b/drivers/lguest/lguest_user.c
index 816d4d12a801..5632ed82798a 100644
--- a/drivers/lguest/lguest_user.c
+++ b/drivers/lguest/lguest_user.c
@@ -167,11 +167,11 @@ static int initialize(struct file *file, const u32 __user *input)
         /* "struct lguest" contains everything we (the Host) know about a
          * Guest. */
         struct lguest *lg;
-        int err, i;
+        int err;
         u32 args[5];
 
-        /* We grab the Big Lguest lock, which protects the global array
-         * "lguests" and multiple simultaneous initializations. */
+        /* We grab the Big Lguest lock, which protects against multiple
+         * simultaneous initializations. */
         mutex_lock(&lguest_lock);
         /* You can't initialize twice!  Close the device and start again... */
         if (file->private_data) {
@@ -184,18 +184,13 @@ static int initialize(struct file *file, const u32 __user *input)
                 goto unlock;
         }
 
-        /* Find an unused guest. */
-        i = find_free_guest();
-        if (i < 0) {
-                err = -ENOSPC;
+        lg = kzalloc(sizeof(*lg), GFP_KERNEL);
+        if (!lg) {
+                err = -ENOMEM;
                 goto unlock;
         }
-        /* OK, we have an index into the "lguest" array: "lg" is a convenient
-         * pointer. */
-        lg = &lguests[i];
 
         /* Populate the easy fields of our "struct lguest" */
-        lg->guestid = i;
         lg->mem_base = (void __user *)(long)args[0];
         lg->pfn_limit = args[1];
         lg->page_offset = args[4];