add missing header + cleanup

Author: clemdiep

so3/arch/arm64/domain.c

@@ -136,7 +136,7 @@ void __setup_dom_pgtable(struct domain *d, addr_t paddr_start, unsigned long map
 		d->grant_pfn[i].free = true;
 	}
 
-	/* Set IPA framebuffer starting address after the grant pfn area */
+	/* Set staring framebuffer ipa address after the grant pfn area */
 	d->fbdev_start_pfn = phys_to_pfn(memslot[slotID].ipa_addr + map_size + 2 * PAGE_SIZE) + NR_GRANT_PFN;
 	fbdev_ipamap_domain(d, slotID);
 #endif /* CONFIG_SOO */

so3/avz/include/avz/domain.h

@@ -118,7 +118,7 @@ struct domain {
 	/* IPA reserved page frame numbers for mapping granted pages belonging to other domains */
 	grant_pfn_t grant_pfn[NR_GRANT_PFN];
 
-	/* IPA reserved starting address for framebuffer mapping */
+	/* IPA reserved starting page frame number for framebuffer mapping */
 	addr_t fbdev_start_pfn;
 #endif /* CONFIG_SOO */
 

so3/avz/include/avz/fbdev_gnt.h

@@ -13,7 +13,6 @@
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
- *
  */
 
 #ifndef FBDEV_GNT_H

so3/avz/include/avz/injector.h

@@ -55,7 +55,7 @@ struct dom_context {
 	/* IPA reserved page frame numbers for granted pages */
 	grant_pfn_t grant_pfn[NR_GRANT_PFN];
 
-	/* IPA reserved start frame number for framebuffer */
+	/* IPA reserved starting page frame number for framebuffer mapping */
 	addr_t fbdev_start_pfn;
 
 	/* Stack frame of this domain */

so3/avz/kernel/fbdev_gnt.c

@@ -1,11 +1,28 @@
+/*
+ * Copyright (C) 2026 Clément Dieperink <clement.dieperink@heig-vd.ch>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
 #include <heap.h>
 #include <avz/fbdev_gnt.h>
 #include <avz/domain.h>
 #include <avz/memslot.h>
 #include <avz/sched.h>
 
 typedef struct {
-	fbdev_pfns_t fbdev;
+	fbdev_pfns_t fbdev_pfns;
 	void *fake_fbdev;
 	int current_slotID;
 } fbdev_priv_t;
@@ -69,16 +86,16 @@ void fbdev_ipamap_domain(struct domain *d, int slotID)
 		return;
 
 	if (slotID == priv.current_slotID)
-		__map_fbdev(d, &priv.fbdev);
+		__map_fbdev(d, &priv.fbdev_pfns);
 	else
-		__map_fake_fbdev(d, &priv.fbdev);
+		__map_fake_fbdev(d, &priv.fbdev_pfns);
 }
 
 void fbdev_set_pfns(fbdev_pfns_t *fbdev)
 {
 	int slotID;
 
-	memcpy(&priv.fbdev, fbdev, sizeof(*fbdev));
+	memcpy(&priv.fbdev_pfns, fbdev, sizeof(*fbdev));
 
 	/* Map framebuffer to all capsules. */
 	for (slotID = MEMSLOT_BASE; slotID < MEMSLOT_NR; slotID++)
@@ -90,11 +107,11 @@ void fbdev_change_focus(int new_slotID)
 {
 	/* Remap old capsule to fake framebuffer */
 	if ((priv.current_slotID >= MEMSLOT_BASE) && memslot[priv.current_slotID].busy)
-		__map_fake_fbdev(domains[priv.current_slotID], &priv.fbdev);
+		__map_fake_fbdev(domains[priv.current_slotID], &priv.fbdev_pfns);
 
 	/* Map the new capsule to the framebuffer */
 	if ((new_slotID >= MEMSLOT_BASE) && memslot[new_slotID].busy)
-		__map_fbdev(domains[new_slotID], &priv.fbdev);
+		__map_fbdev(domains[new_slotID], &priv.fbdev_pfns);
 
 	priv.current_slotID = new_slotID;
 }

so3/soo/drivers/vfbdevfront/vfbdev.c

@@ -50,7 +50,6 @@ typedef struct {
 	uint32_t vres;
 	size_t memory_size;
 	addr_t fb_paddr;
-
 } vfbdev_priv_t;
 
 /* Our unique vfbdev instance. */
@@ -210,16 +209,22 @@ vdrvfront_t vfbdevdrv = { .probe = vfbdev_probe,
 			 .resume = vfbdev_resume,
 			 .connected = vfbdev_connected };
 
+/* Char device associated to the framebuffer */
+
+/**
+ * Retrieve data (resolution, size, fb address) from peer and AVZ.
+ */
 static void retrieve_data(vfbdev_priv_t *priv)
 {
 	vfbdev_request_t *ring_req;
 	vfbdev_response_t *ring_rsp;
 	avz_hyp_t hyp_args;
 
-	if ((priv->memory_size != 0) && (priv->fb_paddr != 0)) {
+	/* Data have already been retrieved */
+	if ((priv->memory_size != 0) && (priv->fb_paddr != 0))
 		return;
-	}
 
+	/* Retrieve resolution and size from peer */
 	vdevfront_processing_begin(vfbdev_dev);
 
 	ring_req = vfbdev_new_ring_request(&priv->vfbdev.ring);
@@ -243,6 +248,7 @@ static void retrieve_data(vfbdev_priv_t *priv)
 
 	vdevfront_processing_end(vfbdev_dev);
 
+	/* Retrieve fb address from AVZ */
 	hyp_args.cmd = AVZ_FBDEV_GET_ME_ADDR;
 	avz_hypercall(&hyp_args);
 	priv->fb_paddr = hyp_args.u.avz_fbdev_addr_args.paddr;
@@ -288,6 +294,7 @@ static int vfbdev_ioctl(int fd, unsigned long cmd, unsigned long args)
 
 	retrieve_data(priv);
 
+	/* Set returned value accordingly to the command */
 	switch (cmd) {
 	case IOCTL_FB_HRES:
 		*((uint32_t *) args) = priv->hres;
@@ -303,7 +310,7 @@ static int vfbdev_ioctl(int fd, unsigned long cmd, unsigned long args)
 
 	default:
 		/* Unknown command. */
-		return -1;
+		return -EINVAL;
 	}
 }
 

so3/soo/include/soo/uapi/soo.h

@@ -73,7 +73,7 @@ typedef struct gnttab_op gnttab_op_t;
 void do_gnttab(gnttab_op_t *args);
 
 /*
- * Framebuffer to set the framebuffer addresses.
+ * Page frame number to set the framebuffer addresses.
  * The physical addresses may be splitted in multiple parts, which requires to have
  * multiple set of strating page frame and page count
  */