pcmcia: pcmcia_dev_present bugfix

pcmcia_dev_present is in and by itself buggy. Add a note specifying
why it is broken, and replace the broken locking -- taking a mutex
is a bad idea in IRQ context, from which this function is rarely
called -- by an atomic_t.

Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>

2 files changed, 6 insertions, 9 deletions

diff --git a/include/pcmcia/ds.h b/include/pcmcia/ds.h
index d57847f2f6c1..aab3c13dc310 100644
--- a/include/pcmcia/ds.h
+++ b/include/pcmcia/ds.h
@@ -26,6 +26,7 @@
 #ifdef __KERNEL__
 #include <linux/device.h>
 #include <pcmcia/ss.h>
+#include <asm/atomic.h>
 
 /*
  * PCMCIA device drivers (16-bit cards only; 32-bit cards require CardBus
@@ -94,10 +95,8 @@ struct pcmcia_device {
         config_req_t            conf;
         window_handle_t         win;
 
-        /* Is the device suspended, or in the process of
-         * being removed? */
+        /* Is the device suspended? */
         u16                     suspended:1;
-        u16                     _removed:1;
 
         /* Flags whether io, irq, win configurations were
          * requested, and whether the configuration is "locked" */
@@ -115,7 +114,7 @@ struct pcmcia_device {
         u16                     has_card_id:1;
         u16                     has_func_id:1;
 
-        u16                     reserved:3;
+        u16                     reserved:4;
 
         u8                      func_id;
         u16                     manf_id;
diff --git a/include/pcmcia/ss.h b/include/pcmcia/ss.h
index 2e488b60bc76..344705cb42f4 100644
--- a/include/pcmcia/ss.h
+++ b/include/pcmcia/ss.h
@@ -224,18 +224,16 @@ struct pcmcia_socket {
 
         /* 16-bit state: */
         struct {
-                /* PCMCIA card is present in socket */
-                u8                      present:1;
                 /* "master" ioctl is used */
                 u8                      busy:1;
-                /* pcmcia module is being unloaded */
-                u8                      dead:1;
                 /* the PCMCIA card consists of two pseudo devices */
                 u8                      has_pfc:1;
 
-                u8                      reserved:4;
+                u8                      reserved:6;
         } pcmcia_state;
 
+        /* non-zero if PCMCIA card is present */
+        atomic_t                        present;
 
 #ifdef CONFIG_PCMCIA_IOCTL
         struct user_info_t              *user;