Kernel/VFS: Cleanup of file descriptor halts

8 files changed, 66 insertions, 138 deletions

diff --git a/kernel/Makefile b/kernel/Makefile
index 3a88d91..c42c95c 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -1,7 +1,7 @@
 CC="i686-sb-gcc"
 AS="i686-sb-as"
-OBJ = arch/i386/boot.o init/kernel.o cpu/gdt.o cpu/reload_gdt.o cpu/idt.o cpu/io.o libc/stdio/print.o drivers/keyboard.o log.o drivers/pit.o libc/string/memcpy.o libc/string/strlen.o libc/string/memcmp.o drivers/ata.o libc/string/memset.o cpu/syscall.o  read_eip.o libc/exit/assert.o process.o libc/string/strcpy.o arch/i386/mmu.o kmalloc.o fs/ext2.o fs/vfs.o fs/devfs.o cpu/spinlock.o random.o libc/string/strcmp.o crypto/ChaCha20/chacha20.o crypto/SHA1/sha1.o fs/tmpfs.o libc/string/isequal.o drivers/pst.o halts.o syscalls/ppoll.o syscalls/ftruncate.o kubsan.o syscalls/mmap.o drivers/serial.o syscalls/accept.o syscalls/bind.o syscalls/socket.o socket.o poll.o fs/fifo.o hashmap/hashmap.o fs/shm.o syscalls/shm.o elf.o ksbrk.o sched/scheduler.o syscalls/stat.o libc/string/copy.o libc/string/strncpy.o drivers/mouse.o libc/string/strlcpy.o libc/string/strcat.o drivers/vbe.o syscalls/msleep.o syscalls/uptime.o syscalls/mkdir.o drivers/pci.o drivers/rtl8139.o network/ethernet.o network/arp.o network/bytes.o network/ipv4.o network/udp.o syscalls/recvfrom.o math.o syscalls/sendto.o signal.o syscalls/kill.o syscalls/sigaction.o network/tcp.o drivers/ahci.o crypto/xoshiro256plusplus/xoshiro256plusplus.o syscalls/chdir.o syscalls/getcwd.o syscalls/isatty.o syscalls/randomfill.o syscalls/open.o syscalls/write.o syscalls/pwrite.o ipc.o syscalls/ipc.o syscalls/port.o syscalls/map_frames.o syscalls/virtual_to_physical.o syscalls/install_irq.o arch/i386/interrupts.o cpu/isr.o lib/stack.o lib/buffered_write.o
-CFLAGS = -O0 -fsanitize=vla-bound,shift-exponent,pointer-overflow,shift,signed-integer-overflow,bounds -ggdb -ffreestanding -Wall -Werror -mgeneral-regs-only -Wimplicit-fallthrough -I./libc/include/ -I. -Wno-pointer-sign -DKERNEL
+OBJ = arch/i386/boot.o init/kernel.o cpu/gdt.o cpu/reload_gdt.o cpu/idt.o cpu/io.o libc/stdio/print.o drivers/keyboard.o log.o drivers/pit.o libc/string/memcpy.o libc/string/strlen.o libc/string/memcmp.o drivers/ata.o libc/string/memset.o cpu/syscall.o  read_eip.o libc/exit/assert.o process.o libc/string/strcpy.o arch/i386/mmu.o kmalloc.o fs/ext2.o fs/vfs.o fs/devfs.o cpu/spinlock.o random.o libc/string/strcmp.o crypto/ChaCha20/chacha20.o crypto/SHA1/sha1.o fs/tmpfs.o libc/string/isequal.o drivers/pst.o halts.o syscalls/ppoll.o syscalls/ftruncate.o kubsan.o syscalls/mmap.o drivers/serial.o syscalls/accept.o syscalls/bind.o syscalls/socket.o socket.o poll.o fs/fifo.o hashmap/hashmap.o fs/shm.o syscalls/shm.o elf.o ksbrk.o sched/scheduler.o syscalls/stat.o libc/string/copy.o libc/string/strncpy.o drivers/mouse.o libc/string/strlcpy.o libc/string/strcat.o drivers/vbe.o syscalls/msleep.o syscalls/uptime.o syscalls/mkdir.o drivers/pci.o drivers/rtl8139.o network/ethernet.o network/arp.o network/bytes.o network/ipv4.o network/udp.o syscalls/recvfrom.o math.o syscalls/sendto.o signal.o syscalls/kill.o syscalls/sigaction.o network/tcp.o drivers/ahci.o crypto/xoshiro256plusplus/xoshiro256plusplus.o syscalls/chdir.o syscalls/getcwd.o syscalls/isatty.o syscalls/randomfill.o syscalls/open.o syscalls/write.o syscalls/pwrite.o ipc.o syscalls/ipc.o syscalls/port.o syscalls/map_frames.o syscalls/virtual_to_physical.o syscalls/install_irq.o arch/i386/interrupts.o cpu/isr.o lib/stack.o lib/buffered_write.o lib/list.o
+CFLAGS = -Ofast -fsanitize=vla-bound,shift-exponent,pointer-overflow,shift,signed-integer-overflow,bounds -ggdb -ffreestanding -Wall -Werror -mgeneral-regs-only -Wimplicit-fallthrough -I./libc/include/ -I. -Wno-pointer-sign -DKERNEL
 #LDFLAGS=-flto -Ofast
 LDFLAGS=
 INCLUDE=-I./includes/ -I../include/ -I./libc/include/
diff --git a/kernel/drivers/pit.c b/kernel/drivers/pit.c
index 108529d..1e9048f 100644
--- a/kernel/drivers/pit.c
+++ b/kernel/drivers/pit.c
@@ -44,11 +44,11 @@ void set_pit_count(u16 hertz) {
 void int_clock(reg_t regs) {
   outb(0x20, 0x20);
   pit_counter++;
-  if (pit_counter >= hertz / 1000) {
+  if (pit_counter*1000 >= hertz) {
     pit_counter = 0;
     clock_num_ms_ticks++;
+    switch_task();
   }
-  switch_task();
 }
 
 void pit_install(void) {
diff --git a/kernel/halts.c b/kernel/halts.c
index 6f60a79..c2b682e 100644
--- a/kernel/halts.c
+++ b/kernel/halts.c
@@ -2,98 +2,37 @@
 #include <halts.h>
 #include <sched/scheduler.h>
 
-int create_disconnect_inode_halt(vfs_inode_t *inode) {
-  volatile process_t *p = get_current_task();
-  int i;
-  for (i = 0; i < 100; i++)
-    if (!p->disconnect_halt_inode[i])
-      break;
-
-  if (p->disconnect_halt_inode[i])
-    return -1;
-
-  p->disconnect_halt_inode[i] = inode;
-  return i;
-}
-
-int create_disconnect_fdhalt(vfs_fd_t *fd) {
-  assert(fd);
-  return create_disconnect_inode_halt(fd->inode);
-}
-
-int create_read_inode_halt(vfs_inode_t *inode) {
-  volatile process_t *p = get_current_task();
-  int i;
-  for (i = 0; i < 100; i++)
-    if (!p->read_halt_inode[i])
-      break;
-
-  if (p->read_halt_inode[i])
-    return -1;
-
-  p->read_halt_inode[i] = inode;
-
-  return i;
-}
-
-int create_read_fdhalt(vfs_fd_t *fd) {
-  assert(fd);
-  return create_read_inode_halt(fd->inode);
-}
-
-int create_write_inode_halt(vfs_inode_t *inode) {
-  volatile process_t *p = get_current_task();
-  int i;
-  for (i = 0; i < 100; i++)
-    if (!p->write_halt_inode[i])
-      break;
-
-  if (p->write_halt_inode[i])
-    return -1;
-
-  p->write_halt_inode[i] = inode;
-  return i;
-}
-
-int create_write_fdhalt(vfs_fd_t *fd) {
-  return create_write_inode_halt(fd->inode);
-}
-
-void unset_read_fdhalt(int i) {
-  get_current_task()->read_halt_inode[i] = NULL;
-}
-
-void unset_write_fdhalt(int i) {
-  get_current_task()->write_halt_inode[i] = NULL;
-}
-
-void unset_disconnect_fdhalt(int i) {
-  get_current_task()->disconnect_halt_inode[i] = NULL;
-}
-
-int isset_fdhalt(vfs_inode_t *read_halts[], vfs_inode_t *write_halts[],
-                 vfs_inode_t *disconnect_halts[]) {
+int isset_fdhalt(process_t *p) {
   int blocked = 0;
-  for (int i = 0; i < 100; i++) {
-    if (!read_halts[i])
-      continue;
-    if (read_halts[i]->has_data) {
+  struct list *read_list = &p->read_list;
+  for (int i = 0;; i++) {
+    vfs_inode_t *inode;
+    if (!list_get(read_list, i, (void **)&inode)) {
+      break;
+    }
+    if (inode->has_data) {
       return 0;
     }
     blocked = 1;
   }
-  for (int i = 0; i < 100; i++) {
-    if (!write_halts[i])
-      continue;
-    if (write_halts[i]->can_write) {
+  struct list *write_list = &p->write_list;
+  for (int i = 0;; i++) {
+    vfs_inode_t *inode;
+    if (!list_get(write_list, i, (void **)&inode)) {
+      break;
+    }
+    if (inode->can_write) {
       return 0;
     }
     blocked = 1;
   }
-  for (int i = 0; i < 100; i++) {
-    if (!disconnect_halts[i])
-      continue;
-    if (!disconnect_halts[i]->is_open) {
+  struct list *disconnect_list = &p->disconnect_list;
+  for (int i = 0;; i++) {
+    vfs_inode_t *inode;
+    if (!list_get(disconnect_list, i, (void **)&inode)) {
+      break;
+    }
+    if (inode->is_open) {
       return 0;
     }
     blocked = 1;
diff --git a/kernel/halts.h b/kernel/halts.h
index 11e47ff..ed0637f 100644
--- a/kernel/halts.h
+++ b/kernel/halts.h
@@ -1,21 +1,7 @@
 #ifndef HALTS_H
 #define HALTS_H
 #include <fs/vfs.h>
+#include <sched/scheduler.h>
 #include <typedefs.h>
-
-typedef struct {
-  u8 *ptr;
-  u8 active;
-} halt_t;
-
-int create_read_fdhalt(vfs_fd_t *fd);
-int create_read_inode_halt(vfs_inode_t *inode);
-void unset_read_fdhalt(int i);
-int create_write_fdhalt(vfs_fd_t *fd);
-int create_write_inode_halt(vfs_inode_t *inode);
-void unset_write_fdhalt(int i);
-int create_disconnect_fdhalt(vfs_fd_t *fd);
-void unset_disconnect_fdhalt(int i);
-int isset_fdhalt(vfs_inode_t *read_halts[], vfs_inode_t *write_halts[],
-                 vfs_inode_t *disconnect_halts[]);
+int isset_fdhalt(process_t *p);
 #endif
diff --git a/kernel/init/kernel.c b/kernel/init/kernel.c
index 45cb9db..6b160a6 100644
--- a/kernel/init/kernel.c
+++ b/kernel/init/kernel.c
@@ -67,7 +67,7 @@ void kernel_main(u32 kernel_end, unsigned long magic, unsigned long addr,
   klog("Syscalls Initalized", LOG_SUCCESS);
 
   pit_install();
-  set_pit_count(2000);
+  set_pit_count(500);
   klog("PIT driver installed", LOG_SUCCESS);
 
   ata_init();
diff --git a/kernel/poll.c b/kernel/poll.c
index 7e9c8e8..0452bc8 100644
--- a/kernel/poll.c
+++ b/kernel/poll.c
@@ -1,14 +1,19 @@
 #include <fs/vfs.h>
 #include <halts.h>
+#include <interrupts.h>
+#include <lib/list.h>
 #include <poll.h>
 #include <sched/scheduler.h>
 
 int poll(struct pollfd *fds, size_t nfds, int timeout) {
   (void)timeout;
   int rc = 0;
-  int read_locks[nfds];
-  int write_locks[nfds];
-  int disconnect_locks[nfds];
+
+  disable_interrupts();
+
+  struct list *read_list = &get_current_task()->read_list;
+  struct list *write_list = &get_current_task()->write_list;
+  struct list *disconnect_list = &get_current_task()->disconnect_list;
   for (size_t i = 0; i < nfds; i++) {
     if (fds[i].fd < 0)
       continue;
@@ -16,26 +21,25 @@ int poll(struct pollfd *fds, size_t nfds, int timeout) {
     if (NULL == f) {
       continue;
     }
-    if (fds[i].events & POLLIN)
-      read_locks[i] = create_read_fdhalt(f);
-    if (fds[i].events & POLLOUT)
-      write_locks[i] = create_write_fdhalt(f);
-    if (fds[i].events & POLLHUP)
-      disconnect_locks[i] = create_disconnect_fdhalt(f);
+
+    if (fds[i].events & POLLIN) {
+      list_add(read_list, f->inode);
+    }
+    if (fds[i].events & POLLOUT) {
+      list_add(write_list, f->inode);
+    }
+    if (fds[i].events & POLLHUP) {
+      list_add(disconnect_list, f->inode);
+    }
   }
 
   switch_task();
+  disable_interrupts();
+
+  list_reset(read_list);
+  list_reset(write_list);
+  list_reset(disconnect_list);
 
-  for (size_t i = 0; i < nfds; i++) {
-    if (fds[i].fd < 0)
-      continue;
-    if (fds[i].events & POLLIN)
-      unset_read_fdhalt(read_locks[i]);
-    if (fds[i].events & POLLOUT)
-      unset_write_fdhalt(write_locks[i]);
-    if (fds[i].events & POLLHUP)
-      unset_disconnect_fdhalt(disconnect_locks[i]);
-  }
   for (size_t i = 0; i < nfds; i++) {
     if (0 > fds[i].fd) {
       fds[i].revents = 0;
@@ -56,5 +60,6 @@ int poll(struct pollfd *fds, size_t nfds, int timeout) {
         rc++;
     }
   }
+  enable_interrupts();
   return rc;
 }
diff --git a/kernel/sched/scheduler.c b/kernel/sched/scheduler.c
index 8cb5af7..5a95c4c 100644
--- a/kernel/sched/scheduler.c
+++ b/kernel/sched/scheduler.c
@@ -119,6 +119,10 @@ process_t *create_process(process_t *p, u32 esp, u32 eip) {
   r->tcb = kcalloc(1, sizeof(struct TCB));
   r->tcb->CR3 = r->cr3->physical_address;
 
+  list_init(&r->read_list);
+  list_init(&r->write_list);
+  list_init(&r->disconnect_list);
+
   // Temporarily switch to the page directory to be able to place the
   // "entry_instruction_pointer" onto the stack.
 
@@ -155,12 +159,6 @@ process_t *create_process(process_t *p, u32 esp, u32 eip) {
     } else {
       r->file_descriptors[i] = NULL;
     }
-    if (i < 20)
-      r->signal_handlers[i] = NULL;
-    r->read_halt_inode[i] = NULL;
-    r->write_halt_inode[i] = NULL;
-    r->disconnect_halt_inode[i] = NULL;
-    r->maps[i] = NULL;
   }
   return r;
 }
@@ -332,8 +330,7 @@ int is_halted(process_t *process) {
     if (process->halts[i])
       return 1;
 
-  if (isset_fdhalt(process->read_halt_inode, process->write_halt_inode,
-                   process->disconnect_halt_inode)) {
+  if (isset_fdhalt(process)) {
     return 1;
   }
   return 0;
@@ -349,7 +346,7 @@ process_t *next_task(process_t *c) {
       if (1 == loop) {
         return s;
       }
-      loop = 1;
+      //      loop = 1;
     }
     c = c->next;
     if (!c)
@@ -387,8 +384,8 @@ void switch_task() {
   if (!current_task) {
     return;
   }
-  disable_interrupts();
 
+  disable_interrupts();
   current_task = next_task((process_t *)current_task);
   active_directory = current_task->cr3;
 
diff --git a/kernel/sched/scheduler.h b/kernel/sched/scheduler.h
index 0580ba0..f185e0f 100644
--- a/kernel/sched/scheduler.h
+++ b/kernel/sched/scheduler.h
@@ -1,9 +1,11 @@
+typedef struct Process process_t;
 #ifndef SCHEDULER_H
 #define SCHEDULER_H
 #include <fs/ext2.h>
 #include <fs/vfs.h>
 #include <halts.h>
 #include <ipc.h>
+#include <lib/list.h>
 #include <lib/stack.h>
 #include <mmu.h>
 #include <signal.h>
@@ -37,8 +39,6 @@ typedef struct {
   uintptr_t handler_ip;
 } signal_t;
 
-typedef struct Process process_t;
-
 typedef struct TCB {
   uint32_t ESP;
   uint32_t CR3;
@@ -64,9 +64,10 @@ struct Process {
   PageDirectory *cr3;
   struct IpcMailbox ipc_mailbox;
   vfs_fd_t *file_descriptors[100];
-  vfs_inode_t *read_halt_inode[100];
-  vfs_inode_t *write_halt_inode[100];
-  vfs_inode_t *disconnect_halt_inode[100];
+
+  struct list read_list;
+  struct list write_list;
+  struct list disconnect_list;
 
   struct stack restore_context_stack;
   struct stack signal_stack;