🆕 sys_open系统调用

kernel/process/process.c

@@ -7,6 +7,7 @@
 #include "../syscall/syscall_num.h"
 #include <mm/slab.h>
 #include <sched/sched.h>
+#include <filesystem/fat32/fat32.h>
 
 extern void system_call(void);
 extern void kernel_thread_func(void);
@@ -72,16 +73,9 @@ void user_level_function()
     long ret = 0;
     //	printk_color(RED,BLACK,"user_level_function task is running\n");
 
-    char string[] = "User level process.\n";
     /*
-    __asm__ __volatile__("leaq	sysexit_return_address(%%rip),	%%rdx	\n\t"
-                         "movq	%%rsp,	%%rcx		\n\t"
-                         "sysenter			\n\t"
-                         "sysexit_return_address:	\n\t"
-                         : "=a"(ret)
-                         : "0"(1), "D"(string)
-                         : "memory");
-                         */
+    // 测试sys put string
+    char string[] = "User level process.\n";
     long err_code = 1;
     ul addr = (ul)string;
     __asm__ __volatile__(
@@ -90,19 +84,26 @@ void user_level_function()
         : "=a"(err_code)
         : "a"(SYS_PUT_STRING), "m"(addr)
         : "memory", "r8");
-    if (err_code == 0)
-    {
-        char str[] = "errno is 0\n";
-        addr = (ul)str;
-        __asm__ __volatile__(
-            "movq %2, %%r8 \n\t"
-            "int $0x80   \n\t"
-            : "=a"(err_code)
-            : "a"(SYS_PUT_STRING), "m"(addr)
-            : "memory", "r8");
-    }
-    // enter_syscall_int(SYS_PRINTF, (ul) "test_sys_printf\n", 0, 0, 0, 0, 0, 0, 0);
-    //  kinfo("Return from syscall id 15...");
+    */
+
+    // 测试sys_open
+    char string[] = "/xx/12.png";
+    long err_code = 1;
+    int zero = 0;
+    uint64_t addr = (ul)string;
+    __asm__ __volatile__(
+        "movq %2, %%r8 \n\t"
+        "movq %3, %%r9 \n\t"
+        "movq %4, %%r10 \n\t"
+        "movq %5, %%r11 \n\t"
+        "movq %6, %%r12 \n\t"
+        "movq %7, %%r13 \n\t"
+        "movq %8, %%r14 \n\t"
+        "movq %9, %%r15 \n\t"
+        "int $0x80   \n\t"
+        : "=a"(err_code)
+        : "a"(SYS_OPEN), "m"(addr), "m"(zero), "m"(zero), "m"(zero), "m"(zero), "m"(zero), "m"(zero), "m"(zero)
+        : "memory", "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15", "rcx", "rdx");
 
     while (1)
         pause();
@@ -151,7 +152,7 @@ ul do_execve(struct pt_regs *regs)
     mm_map_phys_addr_user(addr, alloc_pages(ZONE_NORMAL, 1, PAGE_PGT_MAPPED)->addr_phys, PAGE_2M_SIZE, PAGE_USER_PAGE);
 
     if (!(current_pcb->flags & PF_KTHREAD))
-        current_pcb->addr_limit = KERNEL_BASE_LINEAR_ADDR;
+        current_pcb->addr_limit = USER_MAX_LINEAR_ADDR;
     // 将程序代码拷贝到对应的内存中
     memcpy((void *)0x800000, user_level_function, 1024);
 
@@ -168,6 +169,7 @@ ul do_execve(struct pt_regs *regs)
 ul initial_kernel_thread(ul arg)
 {
     // kinfo("initial proc running...\targ:%#018lx", arg);
+    fat32_init();
 
     struct pt_regs *regs;
 
@@ -377,7 +379,7 @@ unsigned long do_fork(struct pt_regs *regs, unsigned long clone_flags, unsigned
     //  将寄存器信息存储到进程的内核栈空间的顶部
     memcpy((void *)((ul)tsk + STACK_SIZE - sizeof(struct pt_regs)), regs, sizeof(struct pt_regs));
 
-    kdebug("regs.rip = %#018lx", regs->rip);
+    // kdebug("regs.rip = %#018lx", regs->rip);
     // 设置进程的内核栈
     thd->rbp = (ul)tsk + STACK_SIZE;
     thd->rip = regs->rip;

kernel/process/process.h

@@ -16,6 +16,11 @@
 #include "../syscall/syscall.h"
 #include "ptrace.h"
 
+#include <filesystem/VFS/VFS.h>
+
+// 进程最大可拥有的文件描述符数量
+#define PROC_MAX_FD_NUM 16
+
 // 进程的内核栈大小 32K
 #define STACK_SIZE 32768
 
@@ -116,6 +121,10 @@ struct process_control_block
 	long pid;
 	long priority;		  // 优先级
 	long virtual_runtime; // 虚拟运行时间
+
+	// 进程拥有的文件描述符的指针数组
+	// todo: 改用动态指针数组
+	struct vfs_file_t *fds[PROC_MAX_FD_NUM];
 };
 
 // 将进程的pcb和内核栈融合到一起,8字节对齐
@@ -138,7 +147,8 @@ union proc_union
 		.signal = 0,                      \
 		.priority = 2,                    \
 		.preempt_count = 0,               \
-		.cpu_id = 0                       \
+		.cpu_id = 0,                      \
+		.fds = { 0 }                      \
 	}
 
 /**
@@ -211,19 +221,17 @@ struct process_control_block *get_current_pcb()
 #define switch_proc(prev, next)                                                                     \
 	do                                                                                              \
 	{                                                                                               \
-		__asm__ __volatile__("cli	\n\t"                                                             \
-							 "pushq	%%rbp	\n\t"                                                     \
+		__asm__ __volatile__("pushq	%%rbp	\n\t"                                                     \
 							 "pushq	%%rax	\n\t"                                                     \
 							 "movq	%%rsp,	%0	\n\t"                                                  \
 							 "movq	%2,	%%rsp	\n\t"                                                  \
-							 "leaq	switch_proc_ret_addr(%%rip),	%%rax	\n\t"                                           \
+							 "leaq	switch_proc_ret_addr(%%rip),	%%rax	\n\t"                         \
 							 "movq	%%rax,	%1	\n\t"                                                  \
 							 "pushq	%3		\n\t"                                                       \
 							 "jmp	__switch_to	\n\t"                                                 \
-							 "switch_proc_ret_addr:	\n\t"                                                              \
+							 "switch_proc_ret_addr:	\n\t"                                           \
 							 "popq	%%rax	\n\t"                                                      \
 							 "popq	%%rbp	\n\t"                                                      \
-							 "sti	\n\t"                                                             \
 							 : "=m"(prev->thread->rsp), "=m"(prev->thread->rip)                     \
 							 : "m"(next->thread->rsp), "m"(next->thread->rip), "D"(prev), "S"(next) \
 							 : "memory");                                                           \