feat: basic elf32 loader (only LOAD segment is supported)

[lunaix-os.git] / lunaix-os / kernel / fs / vfs.c

diff --git a/lunaix-os/kernel/fs/vfs.c b/lunaix-os/kernel/fs/vfs.c
index c9431bac944992c215230aa31861699e5916ee91..d3d1023b91e383fd3d3fefd45ede3225a6d15386 100644 (file)
--- a/lunaix-os/kernel/fs/vfs.c
+++ b/lunaix-os/kernel/fs/vfs.c
@@ -44,7 +44,6 @@
 */
 
 #include <klibc/string.h>
 */
 
 #include <klibc/string.h>

-#include <lunaix/dirent.h>

 #include <lunaix/foptions.h>
 #include <lunaix/fs.h>
 #include <lunaix/mm/cake.h>
 #include <lunaix/foptions.h>
 #include <lunaix/fs.h>
 #include <lunaix/mm/cake.h>


@@ -53,9 +52,12 @@
 #include <lunaix/process.h>
 #include <lunaix/spike.h>
 #include <lunaix/syscall.h>
 #include <lunaix/process.h>
 #include <lunaix/spike.h>
 #include <lunaix/syscall.h>

+#include <lunaix/syscall_utils.h>

 
 #include <lunaix/fs/twifs.h>
 
 
 #include <lunaix/fs/twifs.h>
 

+#include <usr/sys/dirent_defs.h>
+

 static struct cake_pile* dnode_pile;
 static struct cake_pile* inode_pile;
 static struct cake_pile* file_pile;
 static struct cake_pile* dnode_pile;
 static struct cake_pile* inode_pile;
 static struct cake_pile* file_pile;


@@ -109,13 +111,13 @@ vfs_init()
 }
 
 inline struct hbucket*
 }
 
 inline struct hbucket*

-__dcache_hash(struct v_dnode* parent, uint32_t* hash)
+__dcache_hash(struct v_dnode* parent, u32_t* hash)

 {
 {

-    uint32_t _hash = *hash;
-    // 与parent的指针值做加法，来减小碰撞的可能性。
-    _hash += (uint32_t)parent;
+    u32_t _hash = *hash;

     // 确保低位更加随机
     _hash = _hash ^ (_hash >> VFS_HASHBITS);
     // 确保低位更加随机
     _hash = _hash ^ (_hash >> VFS_HASHBITS);

+    // 与parent的指针值做加法，来减小碰撞的可能性。
+    _hash += (u32_t)parent;

     *hash = _hash;
     return &dnode_cache[_hash & VFS_HASH_MASK];
 }
     *hash = _hash;
     return &dnode_cache[_hash & VFS_HASH_MASK];
 }


@@ -130,7 +132,7 @@ vfs_dcache_lookup(struct v_dnode* parent, struct hstr* str)
         return parent->parent;
     }
 
         return parent->parent;
     }
 

-    uint32_t hash = str->hash;
+    u32_t hash = str->hash;

     struct hbucket* slot = __dcache_hash(parent, &hash);
 
     struct v_dnode *pos, *n;
     struct hbucket* slot = __dcache_hash(parent, &hash);
 
     struct v_dnode *pos, *n;


@@ -163,6 +165,7 @@ vfs_dcache_remove(struct v_dnode* dnode)
     assert(dnode->ref_count == 1);
 
     llist_delete(&dnode->siblings);
     assert(dnode->ref_count == 1);
 
     llist_delete(&dnode->siblings);

+    llist_delete(&dnode->aka_list);

     hlist_delete(&dnode->hash_list);
 
     dnode->parent = NULL;
     hlist_delete(&dnode->hash_list);
 
     dnode->parent = NULL;


@@ -225,8 +228,10 @@ void
 vfs_assign_inode(struct v_dnode* assign_to, struct v_inode* inode)
 {
     if (assign_to->inode) {
 vfs_assign_inode(struct v_dnode* assign_to, struct v_inode* inode)
 {
     if (assign_to->inode) {

+        llist_delete(&assign_to->aka_list);

         assign_to->inode->link_count--;
     }
         assign_to->inode->link_count--;
     }

+    llist_append(&inode->aka_dnodes, &assign_to->aka_list);

     assign_to->inode = inode;
     inode->link_count++;
 }
     assign_to->inode = inode;
     inode->link_count++;
 }


@@ -263,11 +268,11 @@ vfs_pclose(struct v_file* file, pid_t pid)
         atomic_fetch_sub(&file->dnode->ref_count, 1);
         file->inode->open_count--;
 
         atomic_fetch_sub(&file->dnode->ref_count, 1);
         file->inode->open_count--;
 

-        // Prevent dead lock.
-        // This happened when process is terminated while blocking on read.
-        // In that case, the process is still holding the inode lock and it will
-        // never get released.

         /*
         /*

+         * Prevent dead lock.
+         * This happened when process is terminated while blocking on read.
+         * In that case, the process is still holding the inode lock and it
+             will never get released.

          * The unlocking should also include ownership check.
          *
          * To see why, consider two process both open the same file both with
          * The unlocking should also include ownership check.
          *
          * To see why, consider two process both open the same file both with


@@ -297,6 +302,12 @@ vfs_close(struct v_file* file)
     return vfs_pclose(file, __current->pid);
 }
 
     return vfs_pclose(file, __current->pid);
 }
 

+void
+vfs_free_fd(struct v_fd* fd)
+{
+    cake_release(fd_pile, fd);
+}
+

 int
 vfs_fsync(struct v_file* file)
 {
 int
 vfs_fsync(struct v_file* file)
 {


@@ -387,6 +398,7 @@ vfs_d_alloc(struct v_dnode* parent, struct hstr* name)
     memset(dnode, 0, sizeof(*dnode));
     llist_init_head(&dnode->children);
     llist_init_head(&dnode->siblings);
     memset(dnode, 0, sizeof(*dnode));
     llist_init_head(&dnode->children);
     llist_init_head(&dnode->siblings);

+    llist_init_head(&dnode->aka_list);

     mutex_init(&dnode->lock);
 
     dnode->ref_count = ATOMIC_VAR_INIT(0);
     mutex_init(&dnode->lock);
 
     dnode->ref_count = ATOMIC_VAR_INIT(0);


@@ -429,7 +441,7 @@ vfs_d_free(struct v_dnode* dnode)
 }
 
 struct v_inode*
 }
 
 struct v_inode*

-vfs_i_find(struct v_superblock* sb, uint32_t i_id)
+vfs_i_find(struct v_superblock* sb, u32_t i_id)

 {
     struct hbucket* slot = &sb->i_cache[i_id & VFS_HASH_MASK];
     struct v_inode *pos, *n;
 {
     struct hbucket* slot = &sb->i_cache[i_id & VFS_HASH_MASK];
     struct v_inode *pos, *n;


@@ -469,6 +481,7 @@ vfs_i_alloc(struct v_superblock* sb)
     memset(inode, 0, sizeof(*inode));
     mutex_init(&inode->lock);
     llist_init_head(&inode->xattrs);
     memset(inode, 0, sizeof(*inode));
     mutex_init(&inode->lock);
     llist_init_head(&inode->xattrs);

+    llist_init_head(&inode->aka_dnodes);

 
     sb->ops.init_inode(sb, inode);
 
 
     sb->ops.init_inode(sb, inode);
 


@@ -489,7 +502,12 @@ vfs_i_free(struct v_inode* inode)
         pcache_release(inode->pg_cache);
         vfree(inode->pg_cache);
     }
         pcache_release(inode->pg_cache);
         vfree(inode->pg_cache);
     }

-    inode->ops->sync(inode);
+    // we don't need to sync inode.
+    // If an inode can be free, then it must be properly closed.
+    // Hence it must be synced already!
+    if (inode->destruct) {
+        inode->destruct(inode);
+    }

     hlist_delete(&inode->hash_list);
     cake_release(inode_pile, inode);
 }
     hlist_delete(&inode->hash_list);
     cake_release(inode_pile, inode);
 }


@@ -553,19 +571,20 @@ vfs_do_open(const char* path, int options)
 {
     int errno, fd;
     struct v_dnode *dentry, *file;
 {
     int errno, fd;
     struct v_dnode *dentry, *file;

-    struct v_file* ofile = 0;
+    struct v_file* ofile = NULL;

 
     errno = __vfs_try_locate_file(
       path, &dentry, &file, (options & FO_CREATE) ? FLOCATE_CREATE_EMPTY : 0);
 
 
     errno = __vfs_try_locate_file(
       path, &dentry, &file, (options & FO_CREATE) ? FLOCATE_CREATE_EMPTY : 0);
 

-    if (errno || (errno = vfs_open(file, &ofile))) {
-        return errno;
-    }
+    if (!errno && !(errno = vfs_alloc_fdslot(&fd))) {

 
 

-    struct v_inode* o_inode = ofile->inode;
+        if (errno || (errno = vfs_open(file, &ofile))) {
+            return errno;
+        }
+
+        struct v_fd* fd_s = cake_grab(fd_pile);
+        memset(fd_s, 0, sizeof(*fd_s));

 
 

-    if (!errno && !(errno = vfs_alloc_fdslot(&fd))) {
-        struct v_fd* fd_s = vzalloc(sizeof(*fd_s));

         ofile->f_pos = ofile->inode->fsize & -((options & FO_APPEND) != 0);
         fd_s->file = ofile;
         fd_s->flags = options;
         ofile->f_pos = ofile->inode->fsize & -((options & FO_APPEND) != 0);
         fd_s->file = ofile;
         fd_s->flags = options;


@@ -594,7 +613,7 @@ __DEFINE_LXSYSCALL1(int, close, int, fd)
         goto done_err;
     }
 
         goto done_err;
     }
 

-    vfree(fd_s);
+    cake_release(fd_pile, fd_s);

     __current->fdtable->fds[fd] = 0;
 
 done_err:
     __current->fdtable->fds[fd] = 0;
 
 done_err:


@@ -607,13 +626,13 @@ __vfs_readdir_callback(struct dir_context* dctx,
                        const int len,
                        const int dtype)
 {
                        const int len,
                        const int dtype)
 {

-    struct dirent* dent = (struct dirent*)dctx->cb_data;
+    struct lx_dirent* dent = (struct lx_dirent*)dctx->cb_data;

     strncpy(dent->d_name, name, DIRENT_NAME_MAX_LEN);
     dent->d_nlen = len;
     dent->d_type = dtype;
 }
 
     strncpy(dent->d_name, name, DIRENT_NAME_MAX_LEN);
     dent->d_nlen = len;
     dent->d_type = dtype;
 }
 

-__DEFINE_LXSYSCALL2(int, readdir, int, fd, struct dirent*, dent)
+__DEFINE_LXSYSCALL2(int, sys_readdir, int, fd, struct lx_dirent*, dent)

 {
     struct v_fd* fd_s;
     int errno;
 {
     struct v_fd* fd_s;
     int errno;


@@ -1206,6 +1225,12 @@ done:
     return DO_STATUS(errno);
 }
 
     return DO_STATUS(errno);
 }
 

+void
+vfs_ref_file(struct v_file* file)
+{
+    atomic_fetch_add(&file->ref_count, 1);
+}
+

 void
 vfs_ref_dnode(struct v_dnode* dnode)
 {
 void
 vfs_ref_dnode(struct v_dnode* dnode)
 {