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-rw-r--r--src/sys/fs/tmpfs.c250
-rw-r--r--src/sys/include/sys/mount.h3
-rw-r--r--src/sys/os/vfs_init.c1
3 files changed, 253 insertions, 1 deletions
diff --git a/src/sys/fs/tmpfs.c b/src/sys/fs/tmpfs.c
new file mode 100644
index 0000000..4a5c607
--- /dev/null
+++ b/src/sys/fs/tmpfs.c
@@ -0,0 +1,250 @@
+/*
+ * Copyright (c) 2025 Ian Marco Moffett and L5 engineers
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the project nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/types.h>
+#include <sys/mount.h>
+#include <sys/syslog.h>
+#include <sys/errno.h>
+#include <sys/queue.h>
+#include <sys/param.h>
+#include <os/vnode.h>
+#include <os/kalloc.h>
+#include <string.h>
+
+#define TMPFS_NAMEMAX 128
+#define TMPFS_INIT_SIZE 8
+
+/*
+ * Represents a single tmpfs node
+ */
+struct tmpfs_node {
+ char name[TMPFS_NAMEMAX];
+ char *data;
+ size_t len;
+ int ref;
+ TAILQ_ENTRY(tmpfs_node) link;
+};
+
+#define tmpfs_ref(TMP_NODEP) \
+ atomic_inc_int(&(TMP_NODEP)->ref)
+
+static TAILQ_HEAD(, tmpfs_node) tmpfs;
+static struct vop tmpfs_vops;
+
+/*
+ * Create a new tmpfs node
+ *
+ * @name: Name of node to create
+ * @np_res: Result pointer is written here
+ *
+ * Returns zero on success, otherwise a less than
+ * zero value on failure
+ */
+static int
+tmpfs_new(const char *name, struct tmpfs_node **np_res)
+{
+ struct tmpfs_node *np;
+ size_t name_len;
+
+ if (name == NULL) {
+ return -EINVAL;
+ }
+
+ name_len = strlen(name);
+ if (name_len > sizeof(np->name) - 1) {
+ return -ENAMETOOLONG;
+ }
+
+ np = kalloc(sizeof(*np));
+ if (np == NULL) {
+ return -ENOMEM;
+ }
+
+ memset(np, 0, sizeof(*np));
+ np->data = kalloc(TMPFS_INIT_SIZE);
+ if (np->data == NULL) {
+ kfree(np);
+ return -ENOMEM;
+ }
+
+ np->len = TMPFS_INIT_SIZE;
+ np->ref = 1;
+ memset(np->data, 0, TMPFS_INIT_SIZE);
+ memcpy(np->name, name, name_len);
+
+ if (np_res != NULL) {
+ *np_res = np;
+ }
+
+ TAILQ_INSERT_TAIL(&tmpfs, np, link);
+ return 0;
+}
+
+/*
+ * Lookup a tmpfs node by name
+ *
+ * @name: Name to lookup
+ * @np_res: Result is written here
+ */
+static int
+tmpfs_byname(const char *name, struct tmpfs_node **np_res)
+{
+ struct tmpfs_node *npcur;
+ int retval = -ENOENT;
+
+ if (name == NULL || np_res == NULL) {
+ return -EINVAL;
+ }
+
+ TAILQ_FOREACH(npcur, &tmpfs, link) {
+ if (npcur == NULL) {
+ continue;
+ }
+
+ if (strcmp(npcur->name, name) == 0) {
+ retval = 0;
+ *np_res = npcur;
+ break;
+ }
+ }
+
+ return retval;
+}
+
+/*
+ * VFS tmpfs lookup callback
+ */
+static int
+tmpfs_lookup(struct vop_lookup_args *args)
+{
+ struct tmpfs_node *np;
+ struct vnode *vp;
+ int error;
+
+ /* Sanity checks */
+ if (args == NULL)
+ return -EINVAL;
+ if (args->name == NULL)
+ return -EINVAL;
+ if (args->vpp == NULL)
+ return -EINVAL;
+
+ error = tmpfs_byname(args->name, &np);
+ if (error < 0) {
+ return error;
+ }
+
+ error = vfs_valloc(&vp, VTYPE_FILE, 0);
+ if (error < 0) {
+ return error;
+ }
+
+ /* Ref that node and give it */
+ tmpfs_ref(np);
+ vp->data = np;
+ vp->vops = &tmpfs_vops;
+ *args->vpp = vp;
+ return 0;
+}
+
+/*
+ * Create a tmpfs node
+ */
+static int
+tmpfs_create(struct vop_create_args *args)
+{
+ struct nameidata *ndp;
+ struct tmpfs_node *np = NULL;
+
+ if (args == NULL) {
+ return -EINVAL;
+ }
+
+ if ((ndp = args->ndp) == NULL) {
+ return -EINVAL;
+ }
+
+ /* Does it already exist? */
+ if (tmpfs_byname(ndp->path, &np) == 0) {
+ return -EEXIST;
+ }
+
+ return tmpfs_new(ndp->path, NULL);
+}
+
+/*
+ * Initialize the temporary filesystem
+ */
+static int
+tmpfs_init(struct fs_info *fip)
+{
+ TAILQ_INIT(&tmpfs);
+ return 0;
+}
+
+/*
+ * Mount the filesystem
+ */
+static int
+tmpfs_mount(struct fs_info *fip, struct mount_args *margs)
+{
+ int error;
+ struct vnode *vp;
+
+ if (fip == NULL || margs == NULL) {
+ return -1;
+ }
+
+ /* Allocate a vnode for this mountpoint */
+ error = vfs_valloc(&margs->vp_res, VTYPE_DIR, 0);
+ if (error < 0) {
+ return error;
+ }
+
+ vp = margs->vp_res;
+ vp->vops = &tmpfs_vops;
+ return 0;
+}
+
+static int
+tmpfs_reclaim(struct vnode *vp, int flags)
+{
+ return 0;
+}
+
+static struct vop tmpfs_vops = {
+ .lookup = tmpfs_lookup,
+ .create = tmpfs_create,
+ .reclaim = tmpfs_reclaim
+};
+
+struct vfsops g_tmpfs_vfsops = {
+ .init = tmpfs_init,
+ .mount = tmpfs_mount,
+};
diff --git a/src/sys/include/sys/mount.h b/src/sys/include/sys/mount.h
index 4a190a4..5f6fa6b 100644
--- a/src/sys/include/sys/mount.h
+++ b/src/sys/include/sys/mount.h
@@ -42,6 +42,7 @@
*/
#define MOUNT_INITRD "initrd" /* Initial ramdisk */
#define MOUNT_DEVFS "devfs" /* Device filesystem */
+#define MOUNT_TMPFS "tmpfs" /* Temporary filesystem */
/*
* The mount system call
@@ -66,6 +67,7 @@ struct mount;
/* Filesystem vfsops */
extern struct vfsops g_omar_vfsops;
extern struct vfsops g_devfs_vfsops;
+extern struct vfsops g_tmpfs_vfsops;
/*
* Represents a mountpoint
@@ -133,7 +135,6 @@ struct fs_info {
*/
#define FS_ATTR_IMAGE BIT(0) /* Is an image kind e.g., OSMORA OMAR */
-
/*
* VFS operations vector
*
diff --git a/src/sys/os/vfs_init.c b/src/sys/os/vfs_init.c
index 90747d6..1b6f815 100644
--- a/src/sys/os/vfs_init.c
+++ b/src/sys/os/vfs_init.c
@@ -40,6 +40,7 @@
static struct fs_info fstab[] = {
{ MOUNT_INITRD, &g_omar_vfsops, 0 },
{ MOUNT_DEVFS, &g_devfs_vfsops, 0 },
+ { MOUNT_TMPFS, &g_tmpfs_vfsops, 0 }
};
/*
generated by cgit v1.2.3 (git 2.39.1) at 2025-10-18 20:55:55 +0000