Changeset 407 for trunk/hal/generic/hal_gpt.h

Timestamp:

Nov 7, 2017, 3:08:12 PM (6 years ago)

Author:

alain

Message:

First implementation of fork/exec.

File:

• trunk/hal/generic/hal_gpt.h (modified) (5 diffs)

trunk/hal/generic/hal_gpt.h

@@ -43 +43 @@
 
 struct page_s;
+struct process_s;
 
 /****************************************************************************************
@@ -48 +49 @@
  ***************************************************************************************/
 
-#define GPT_MAPPED      0x0001  /*! PTE is mapped                                 */
-#define GPT_SMALL       0x0002  /*! PTE is a small page                           */
-#define GPT_READABLE    0x0004  /*! PTE is readable                               */
-#define GPT_WRITABLE    0x0008  /*! PTE is writable                               */
-#define GPT_EXECUTABLE  0x0010  /*! PTE is executable                             */
-#define GPT_CACHABLE    0x0020  /*! PTE can be cached                             */
-#define GPT_USER        0x0040  /*! PTE is user accessible                        */
-#define GPT_DIRTY       0x0080  /*! PTE has been "recently" written               */
-#define GPT_ACCESSED    0x0100  /*! PTE has been "recently" accessed              */
-#define GPT_GLOBAL      0x0200  /*! PTE is kept in TLB at context switch          */
-#define GPT_COW         0x0400  /*! PTE must be copied on write                   */
-#define GPT_SWAP        0x0800  /*! PTE swapped on disk (not implemented yet)     */
-#define GPT_LOCKED      0x1000  /*! PTE is protected against concurrent access    */
+#define GPT_MAPPED      0x0001       /*! PTE is mapped                                 */
+#define GPT_SMALL       0x0002       /*! PTE is a small page                           */
+#define GPT_READABLE    0x0004       /*! PTE is readable                               */
+#define GPT_WRITABLE    0x0008       /*! PTE is writable                               */
+#define GPT_EXECUTABLE  0x0010       /*! PTE is executable                             */
+#define GPT_CACHABLE    0x0020       /*! PTE can be cached                             */
+#define GPT_USER        0x0040       /*! PTE is user accessible                        */
+#define GPT_DIRTY       0x0080       /*! PTE has been "recently" written               */
+#define GPT_ACCESSED    0x0100       /*! PTE has been "recently" accessed              */
+#define GPT_GLOBAL      0x0200       /*! PTE is kept in TLB at context switch          */
+#define GPT_COW         0x0400       /*! PTE must be copied on write                   */
+#define GPT_SWAP        0x0800       /*! PTE swapped on disk (not implemented yet)     */
+#define GPT_LOCKED      0x1000       /*! PTE is protected against concurrent access    */
 
 /****************************************************************************************
@@ -70 +71 @@
         void           * ptr;    /*! local pointer on GPT root                             */
         ppn_t            ppn;    /*! PPN of GPT root                                       */
-        struct page_s  * page;   /*! local pointer on GPT root page descriptor             */
 }
 gpt_t;
@@ -98 +98 @@
  * This function prints on the kernel terminal the content of a generic page table.
  ****************************************************************************************
- * @ gpt     : pointer on generic page table descriptor.
- * @ pid     : process identifier.
- ***************************************************************************************/
-void hal_gpt_print( gpt_t * gpt,
-                    pid_t   pid );
+ * @ process : pointer on local process descriptor.
+ ***************************************************************************************/
+void hal_gpt_display( struct process_s * process );
 
 /****************************************************************************************
@@ -169 +167 @@
 
 /****************************************************************************************
- * This function copies all valid entries from the source <src_gpt> to the <dst_gpt>.
- * The <src_gpt> and the <dst_gpt> point on the same physical pages.
- * If the <cow> argument is true, the GPT_WRITABLE attribute is reset for all writable
- * entries in both <src_gpt> and <dst_gpt>, and the PG_COW flag is registered in all
- * writable physical page descriptors, to support the Copy-On-Write mechanism.
+ * This function is used to implement the "fork" system call: It copies all valid GPT
+ * entries for a given vseg identified by the <vpn_base> and <vpn_size> arguments,
+ * from the source <src_gpt> to the <dst_gpt>. 
+ * It optionnally activates the "Copy on Write" mechanism: when the <cow> argument is
+ * true, the GPT_WRITABLE flag is reset, and the GPT_COW flag is set for each valid 
+ * entry in the destination GPT (The data page will be dynamically allocated an copied
+ * when a write access is detected).
  ****************************************************************************************
  * @ dst_gpt   : [in]  pointer on the destination GPT.
  * @ src_gpt   : [in]  pointer on the source GPT.
+ * @ vpn_base  : [in]  first vpn in vseg.
+ * @ vpn_size  : [in]  number of pages in vseg.
  * @ cow       : [in]  activate the COPY-On-Write mechanism if true.
  ***************************************************************************************/
 error_t hal_gpt_copy( gpt_t    * dst_gpt,
                       gpt_t    * src_gpt,
+                      vpn_t      vpn_base,
+                      vpn_t      vpn_size,
                       bool_t     cow );
 
+/****************************************************************************************
+ * This function returns GPT_COW flag for a PTE defined by <gpt> and <vpn> arguments.
+ ****************************************************************************************
+ * @ gpt       : [in]  pointer on the page table
+ * @ vpn       : [in]  virtual page number
+ * @ returns true if GPT_COW is set.
+ ***************************************************************************************/
+bool_t hal_gpt_pte_is_cow( gpt_t * gpt,
+                           vpn_t   vpn );
+
 
 #endif  /* _GPT_H_ */