New syscalls vfsavailmounts() and vfsmountstat() to get info about current VFS mountpoints

kernel/syscall/syscall.c

@@ -32,6 +32,8 @@ SyscallFn SYSCALL_TABLE[SYSCALLS_MAX] = {
 
   [SYS_VFSMOUNT]   = &sys_vfsmount,
   [SYS_VFSUNMOUNT] = &sys_vfsunmount,
+  [SYS_VFSAVAILMOUNTS] = &sys_vfsavailmounts,
+  [SYS_VFSMOUNTSTAT]   = &sys_vfsmountstat,
 
   [SYS_IPC_PIPEREAD]    = &sys_ipc_piperead,
   [SYS_IPC_PIPEWRITE]   = &sys_ipc_pipewrite,

kernel/syscall/vfs.c

@@ -6,12 +6,14 @@
 #include "vfs.h"
 #include "errors.h"
 #include "sysdefs/dev.h"
+#include "sysdefs/vfs.h"
 #include "vfs/vfs.h"
 #include "spinlock/spinlock.h"
 #include "dev/dev.h"
 #include "proc/proc.h"
 #include "storedev/storedev.h"
 #include "util/util.h"
+#include "hshtb.h"
 
 int32_t SYSCALL4(sys_vfsmount, mountpoint1, fstypestr1, devid1, format1) {
   int32_t ret = E_OK;
@@ -63,3 +65,59 @@ int32_t SYSCALL1(sys_vfsunmount, mountpoint1) {
 done:
   return ret;
 }
+
+int32_t SYSCALL1(sys_vfsavailmounts, availmounts1) {
+  VfsAvailMounts *availmounts = (VfsAvailMounts *)availmounts1;
+  if (availmounts == NULL) {
+    return E_INVALIDARGUMENT;
+  }
+
+  spinlock_acquire(&VFS_TABLE.spinlock);
+  for (size_t i = 0; i < VFS_MOUNTPOINTS_MAX; i++) {
+    VfsMountPoint *vmp = &VFS_TABLE.mountpoints[i];
+    if (vmp->_hshtbstate == HSHTB_TAKEN) {
+      hal_memcpy(availmounts->labels[i], vmp->label, VFS_MOUNTPOINT_LABEL_MAX);
+      availmounts->fieldavail[i] = 1;
+    }
+  }
+  spinlock_release(&VFS_TABLE.spinlock);
+
+  return E_OK;
+}
+
+int32_t SYSCALL2(sys_vfsmountstat, statbuf1, label1) {
+  VfsMountStat *statbuf = (VfsMountStat *)statbuf1;
+  if (statbuf == NULL) {
+    return E_INVALIDARGUMENT;
+  }
+
+  char *label = (char *)label1;
+  if (label == NULL) {
+    return E_INVALIDARGUMENT;
+  }
+
+  VfsMountPoint *vmp = NULL;
+  spinlock_acquire(&VFS_TABLE.spinlock);
+  HSHTB_GET(VFS_TABLE.mountpoints, label, label, vmp);
+  spinlock_release(&VFS_TABLE.spinlock);
+
+  if (vmp == NULL) {
+    return E_NOENTRY;
+  }
+
+  hal_memcpy(statbuf->label, vmp->label, sizeof(statbuf->label));
+  statbuf->fstype = vmp->fstype;
+  
+  StoreDev *vmpsd = vmp->backingsd;
+  spinlock_acquire(&DEVTABLE.spinlock);
+  for (size_t i = 0; i < LEN(DEVTABLE.devs); i++) {
+    Dev *dev = &DEVTABLE.devs[i];
+    if (dev->extra != NULL && ((StoreDev *)dev->extra)->_magic == STOREDEV_MAGIC && vmpsd == dev->extra) {
+      hal_memcpy(statbuf->devname, dev->ident, sizeof(statbuf->devname));
+      break;
+    }
+  }
+  spinlock_release(&DEVTABLE.spinlock);
+
+  return E_OK;
+}

kernel/syscall/vfs.h

@@ -7,5 +7,7 @@
 
 int32_t SYSCALL4(sys_vfsmount, mountpoint1, fstypestr1, devid1, format1);
 int32_t SYSCALL1(sys_vfsunmount, mountpoint1);
+int32_t SYSCALL1(sys_vfsavailmounts, availmounts1);
+int32_t SYSCALL2(sys_vfsmountstat, statbuf1, label1);
 
 #endif // SYSCALL_VFS_H_

share/sysdefs/syscall.h

@@ -9,6 +9,8 @@
 #define SYS_RAND       9
 #define SYS_VFSMOUNT   10
 #define SYS_VFSUNMOUNT 11
+#define SYS_VFSAVAILMOUNTS 2
+#define SYS_VFSMOUNTSTAT   3
 #define SYS_IPC_PIPEREAD    12
 #define SYS_IPC_PIPEWRITE   13
 #define SYS_IPC_PIPEMAKE    14

share/sysdefs/vfs.h

@@ -0,0 +1,15 @@
+#ifndef SHARE_SYSDEFS_VFS_H_
+#define SHARE_SYSDEFS_VFS_H_
+
+typedef struct {
+  char label[128];
+  int32_t fstype;
+  char devname[0x100];
+} VfsMountStat;
+
+typedef struct {
+  char labels[30][128];
+  uint8_t fieldavail[30];
+} VfsAvailMounts;
+
+#endif // SHARE_SYSDEFS_VFS_H_