Integrate PIC support into context switching

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@1900 42af7a65-404d-4744-a932-0658087f49c3

include/nuttx/binfmt.h

@@ -43,6 +43,7 @@
 #include <nuttx/config.h>
 #include <sys/types.h>
 #include <nxflat.h>
+#include <nuttx/sched.h>
 
 /****************************************************************************
  * Pre-processor Definitions
@@ -65,7 +66,7 @@ struct binary_s
 
   main_t       entrypt;              /* Entry point into a program module */
   FAR void    *ispace;               /* Memory-mapped, I-space (.text) address */
-  FAR void    *dspace;               /* Address of the allocated .data/.bss space */
+  FAR struct dspace_s *dspace;       /* Address of the allocated .data/.bss space */
   size_t       isize;                /* Size of the I-space region (needed for munmap) */
   size_t       stacksize;            /* Size of the stack in bytes (unallocated) */
 };

include/nuttx/nxflat.h

@@ -40,7 +40,9 @@
  * Included Files
  ****************************************************************************/
 
+#include <nuttx/config.h>
 #include <nxflat.h>
+#include <nuttx/sched.h>
 
 /****************************************************************************
  * Pre-processor Definitions
@@ -61,29 +63,29 @@ struct nxflat_loadinfo_s
    * text section instance in the system for each module.
    */
 
-  uint32 ispace;       /* Address where hdr/text is loaded */
-  uint32 entryoffs;    /* Offset from ispace to entry point */
-  uint32 isize;        /* Size of ispace. */
+  uint32 ispace;           /* Address where hdr/text is loaded */
+  uint32 entryoffs;        /* Offset from ispace to entry point */
+  uint32 isize;            /* Size of ispace. */
 
   /* Data Space (DSpace): This region contains all information that in referenced
    * as data (other than the stack which is separately allocated).  There will be
    * a unique instance of DSpace (and stack) for each instance of a process.
    */
 
-  uint32 dspace;       /* Address where data/bss/etc. is loaded */
-  uint32 datasize;     /* Size of data segment in dspace */
-  uint32 bsssize;      /* Size of bss segment in dspace */
-  uint32 stacksize;    /* Size of stack (not allocated) */
-  uint32 dsize;        /* Size of dspace (may be large than parts) */
+  struct dspace_s *dspace; /* Allocated D-Space (data/bss/etc) */
+  uint32 datasize;         /* Size of data segment in dspace */
+  uint32 bsssize;          /* Size of bss segment in dspace */
+  uint32 stacksize;        /* Size of stack (not allocated) */
+  uint32 dsize;            /* Size of dspace (may be large than parts) */
 
   /* This is temporary memory where relocation records will be loaded. */
 
-  uint32 relocstart;   /* Start of array of struct flat_reloc */
-  uint32 reloccount;   /* Number of elements in reloc array */
+  uint32 relocstart;       /* Start of array of struct flat_reloc */
+  uint32 reloccount;       /* Number of elements in reloc array */
 
   /* File descriptors */
 
-  int    filfd;        /* Descriptor for the file being loaded */
+  int    filfd;            /* Descriptor for the file being loaded */
 
   const struct nxflat_hdr_s  *header; /* A reference to the flat file header */
 };

include/nuttx/sched.h

@@ -161,6 +161,18 @@ typedef struct environ_s environ_t;
 # define SIZEOF_ENVIRON_T(alloc) (sizeof(environ_t) + alloc - 1)
 #endif
 
+/* This structure describes a reference counted D-Space region */
+
+struct dspace_s
+{
+  uint32 crefs;               /* This is the number of pthreads that shared the
+                               * the same D-Space.
+                               */
+  ubyte  region[1];           /* Beginning of the allocated region */
+};
+
+#define SIZEOF_DSPACE_S(n) (sizeof(struct dspace_s) - 1 + (n))
+
 /* This is the task control block (TCB) */
 
 struct _TCB
@@ -217,7 +229,7 @@ struct _TCB
   /* External Module Support ****************************************************/
 
 #ifdef CONFIG_PIC
-  FAR void *picbase;                     /* Allocated area for .bss and .data   */
+  FAR struct dspace_s *dspace;           /* Allocated area for .bss and .data   */
 #endif
 
   /* POSIX Thread Specific Data *************************************************/