Changeset 68a552f in mainline

Timestamp:

2021-02-22T19:52:08Z (3 years ago)

Author:

Jiri Svoboda <jiri@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

26853ebc

Parents:

2ab8ab3

Message:

Efficient way of rendering to the console via shared buffer

Makes congfx reasonably fast

Location:

uspace

Files:

• app/terminal/terminal.c (modified) (9 diffs)
• app/terminal/terminal.h (modified) (2 diffs)
• lib/c/generic/io/con_srv.c (modified) (4 diffs)
• lib/c/generic/io/console.c (modified) (3 diffs)
• lib/c/include/io/con_srv.h (modified) (3 diffs)
• lib/c/include/io/console.h (modified) (3 diffs)
• lib/c/include/ipc/console.h (modified) (2 diffs)
• lib/congfx/private/console.h (modified) (3 diffs)
• lib/congfx/src/console.c (modified) (11 diffs)
• srv/hid/console/console.c (modified) (5 diffs)

uspace/app/terminal/terminal.c

@@ -37 +37 @@
 #include <adt/list.h>
 #include <adt/prodcons.h>
+#include <as.h>
 #include <errno.h>
 #include <fbfont/font-8x16.h>
@@ -49 +50 @@
 #include <task.h>
 #include <stdarg.h>
+#include <stdio.h>
 #include <stdlib.h>
 #include <str.h>
@@ -86 +88 @@
 static void term_set_cursor_visibility(con_srv_t *, bool);
 static errno_t term_get_event(con_srv_t *, cons_event_t *);
+static errno_t term_map(con_srv_t *, sysarg_t, sysarg_t, charfield_t **);
+static void term_unmap(con_srv_t *);
+static void term_buf_update(con_srv_t *, sysarg_t, sysarg_t, sysarg_t,
+    sysarg_t);
 
 static con_ops_t con_ops = {
@@ -102 +108 @@
         .set_rgb_color = term_set_rgb_color,
         .set_cursor_visibility = term_set_cursor_visibility,
-        .get_event = term_get_event
+        .get_event = term_get_event,
+        .map = term_map,
+        .unmap = term_unmap,
+        .update = term_buf_update
 };
 
@@ -344 +353 @@
                                 charfield_t *back_field =
                                     chargrid_charfield_at(term->backbuf, x, y);
-                                bool update = false;
+                                bool cupdate = false;
 
                                 if ((front_field->flags & CHAR_FLAG_DIRTY) ==
@@ -350 +359 @@
                                         if (front_field->ch != back_field->ch) {
                                                 back_field->ch = front_field->ch;
-                                                update = true;
+                                                cupdate = true;
                                         }
 
@@ -356 +365 @@
                                             back_field->attrs)) {
                                                 back_field->attrs = front_field->attrs;
-                                                update = true;
+                                                cupdate = true;
                                         }
 
@@ -362 +371 @@
                                 }
 
-                                if (update) {
+                                if (cupdate) {
                                         term_update_char(term, &pixelmap, sx, sy, x, y);
                                         update = true;
@@ -645 +654 @@
 }
 
+/** Create shared buffer for efficient rendering.
+ *
+ * @param srv Console server
+ * @param cols Number of columns in buffer
+ * @param rows Number of rows in buffer
+ * @param rbuf Place to store pointer to new sharable buffer
+ *
+ * @return EOK on sucess or an error code
+ */
+static errno_t term_map(con_srv_t *srv, sysarg_t cols, sysarg_t rows,
+    charfield_t **rbuf)
+{
+        terminal_t *term = srv_to_terminal(srv);
+        void *buf;
+
+        fibril_mutex_lock(&term->mtx);
+
+        if (term->ubuf != NULL) {
+                fibril_mutex_unlock(&term->mtx);
+                return EBUSY;
+        }
+
+        buf = as_area_create(AS_AREA_ANY, cols * rows * sizeof(charfield_t),
+            AS_AREA_READ | AS_AREA_WRITE | AS_AREA_CACHEABLE, AS_AREA_UNPAGED);
+        if (buf == AS_MAP_FAILED) {
+                fibril_mutex_unlock(&term->mtx);
+                return ENOMEM;
+        }
+
+        term->ucols = cols;
+        term->urows = rows;
+        term->ubuf = buf;
+        fibril_mutex_unlock(&term->mtx);
+
+        *rbuf = buf;
+        return EOK;
+}
+
+/** Delete shared buffer.
+ *
+ * @param srv Console server
+ */
+static void term_unmap(con_srv_t *srv)
+{
+        terminal_t *term = srv_to_terminal(srv);
+        void *buf;
+
+        fibril_mutex_lock(&term->mtx);
+
+        buf = term->ubuf;
+        term->ubuf = NULL;
+
+        if (buf != NULL)
+                as_area_destroy(buf);
+
+        fibril_mutex_unlock(&term->mtx);
+}
+
+/** Update area of terminal from shared buffer.
+ *
+ * @param srv Console server
+ * @param c0 Column coordinate of top-left corner (inclusive)
+ * @param r0 Row coordinate of top-left corner (inclusive)
+ * @param c1 Column coordinate of bottom-right corner (exclusive)
+ * @param r1 Row coordinate of bottom-right corner (exclusive)
+ */
+static void term_buf_update(con_srv_t *srv, sysarg_t c0, sysarg_t r0,
+    sysarg_t c1, sysarg_t r1)
+{
+        terminal_t *term = srv_to_terminal(srv);
+        charfield_t *ch;
+        sysarg_t col, row;
+
+        fibril_mutex_lock(&term->mtx);
+
+        if (term->ubuf == NULL) {
+                fibril_mutex_unlock(&term->mtx);
+                return;
+        }
+
+        /* Make sure we have meaningful coordinates, within bounds */
+
+        if (c1 > term->ucols)
+                c1 = term->ucols;
+        if (c1 > term->cols)
+                c1 = term->cols;
+        if (c0 >= c1) {
+                fibril_mutex_unlock(&term->mtx);
+                return;
+        }
+        if (r1 > term->urows)
+                r1 = term->urows;
+        if (r1 > term->rows)
+                r1 = term->rows;
+        if (r0 >= r1) {
+                fibril_mutex_unlock(&term->mtx);
+                return;
+        }
+
+        /* Update front buffer from user buffer */
+
+        for (row = r0; row < r1; row++) {
+                for (col = c0; col < c1; col++) {
+                        ch = chargrid_charfield_at(term->frontbuf, col, row);
+                        *ch = term->ubuf[row * term->ucols + col];
+                }
+        }
+
+        fibril_mutex_unlock(&term->mtx);
+
+        /* Update terminal */
+        term_update(term);
+        gfx_update(term->gc);
+}
+
 static void deinit_terminal(terminal_t *term)
 {

uspace/app/terminal/terminal.h

@@ -1 +1 @@
 /*
- * Copyright (c) 2019 Jiri Svoboda
+ * Copyright (c) 2021 Jiri Svoboda
  * Copyright (c) 2012 Petr Koupy
  * All rights reserved.
@@ -85 +85 @@
         sysarg_t top_row;
 
+        sysarg_t ucols;
+        sysarg_t urows;
+        charfield_t *ubuf;
+
         service_id_t dsid;
         con_srvs_t srvs;

uspace/lib/c/generic/io/con_srv.c

@@ -1 +1 @@
 /*
- * Copyright (c) 2012 Jiri Svoboda
+ * Copyright (c) 2021 Jiri Svoboda
  * All rights reserved.
  *
@@ -34 +34 @@
  * @brief Console protocol server stub
  */
+#include <as.h>
 #include <errno.h>
 #include <io/cons_event.h>
@@ -307 +308 @@
 }
 
+/** Create shared buffer for efficient rendering */
+static void con_map_srv(con_srv_t *srv, ipc_call_t *icall)
+{
+        errno_t rc;
+        charfield_t *buf;
+        sysarg_t cols, rows;
+        ipc_call_t call;
+        size_t size;
+
+        if (srv->srvs->ops->map == NULL || srv->srvs->ops->unmap == NULL) {
+                async_answer_0(icall, ENOTSUP);
+                return;
+        }
+
+        cols = ipc_get_arg1(icall);
+        rows = ipc_get_arg2(icall);
+
+        if (!async_share_in_receive(&call, &size)) {
+                async_answer_0(icall, EINVAL);
+                return;
+        }
+
+        /* Check size */
+        if (size != PAGES2SIZE(SIZE2PAGES(cols * rows * sizeof(charfield_t)))) {
+                async_answer_0(&call, EINVAL);
+                async_answer_0(icall, EINVAL);
+                return;
+        }
+
+        rc = srv->srvs->ops->map(srv, cols, rows, &buf);
+        if (rc != EOK) {
+                async_answer_0(&call, rc);
+                async_answer_0(icall, rc);
+                return;
+        }
+
+        rc = async_share_in_finalize(&call, buf, AS_AREA_READ |
+            AS_AREA_WRITE | AS_AREA_CACHEABLE);
+        if (rc != EOK) {
+                srv->srvs->ops->unmap(srv);
+                async_answer_0(icall, EIO);
+                return;
+        }
+
+        async_answer_0(icall, EOK);
+}
+
+/** Delete shared buffer */
+static void con_unmap_srv(con_srv_t *srv, ipc_call_t *icall)
+{
+        if (srv->srvs->ops->unmap == NULL) {
+                async_answer_0(icall, ENOTSUP);
+                return;
+        }
+
+        srv->srvs->ops->unmap(srv);
+        async_answer_0(icall, EOK);
+}
+
+/** Update console area from shared buffer */
+static void con_update_srv(con_srv_t *srv, ipc_call_t *icall)
+{
+        sysarg_t c0, r0, c1, r1;
+
+        c0 = ipc_get_arg1(icall);
+        r0 = ipc_get_arg2(icall);
+        c1 = ipc_get_arg3(icall);
+        r1 = ipc_get_arg4(icall);
+
+        if (srv->srvs->ops->update == NULL) {
+                async_answer_0(icall, ENOTSUP);
+                return;
+        }
+
+        srv->srvs->ops->update(srv, c0, r0, c1, r1);
+        async_answer_0(icall, EOK);
+}
+
 static con_srv_t *con_srv_create(con_srvs_t *srvs)
 {
@@ -412 +491 @@
                         con_get_event_srv(srv, &call);
                         break;
+                case CONSOLE_MAP:
+                        con_map_srv(srv, &call);
+                        break;
+                case CONSOLE_UNMAP:
+                        con_unmap_srv(srv, &call);
+                        break;
+                case CONSOLE_UPDATE:
+                        con_update_srv(srv, &call);
+                        break;
                 default:
                         async_answer_0(&call, ENOTSUP);

uspace/lib/c/generic/io/console.c

@@ -1 +1 @@
 /*
+ * Copyright (c) 2021 Jiri Svoboda
  * Copyright (c) 2006 Josef Cejka
  * Copyright (c) 2006 Jakub Vana
- * Copyright (c) 2008 Jiri Svoboda
  * All rights reserved.
  *
@@ -35 +35 @@
  */
 
+#include <as.h>
 #include <libc.h>
 #include <async.h>
@@ -264 +265 @@
 }
 
+/** Create a shared buffer for fast rendering to the console.
+ *
+ * @param ctrl Console
+ * @param cols Number of columns
+ * @param rows Number of rows
+ * @param rbuf Place to store pointer to the shared buffer
+ * @return EOK on success or an error code
+ */
+errno_t console_map(console_ctrl_t *ctrl, sysarg_t cols, sysarg_t rows,
+    charfield_t **rbuf)
+{
+        async_exch_t *exch = NULL;
+        void *buf;
+        aid_t req;
+        ipc_call_t answer;
+        size_t asize;
+        errno_t rc;
+
+        exch = async_exchange_begin(ctrl->output_sess);
+        req = async_send_2(exch, CONSOLE_MAP, cols, rows, &answer);
+        if (rc != EOK)
+                goto error;
+
+        asize = PAGES2SIZE(SIZE2PAGES(cols * rows * sizeof(charfield_t)));
+
+        rc = async_share_in_start_0_0(exch, asize, &buf);
+        if (rc != EOK) {
+                async_forget(req);
+                goto error;
+        }
+
+        async_exchange_end(exch);
+        exch = NULL;
+
+        async_wait_for(req, &rc);
+        if (rc != EOK)
+                goto error;
+
+        *rbuf = (charfield_t *)buf;
+        return EOK;
+error:
+        if (exch != NULL)
+                async_exchange_end(exch);
+        return rc;
+}
+
+/** Unmap console shared buffer.
+ *
+ * @param ctrl Console
+ * @param buf Buffer
+ */
+void console_unmap(console_ctrl_t *ctrl, charfield_t *buf)
+{
+        as_area_destroy(buf);
+}
+
+/** Update console rectangle from shared buffer.
+ *
+ * @param ctrl Console
+ * @param c0 Column coordinate of top-left corner (inclusive)
+ * @param r0 Row coordinate of top-left corner (inclusive)
+ * @param c1 Column coordinate of bottom-right corner (exclusive)
+ * @param r1 Row coordinate of bottom-right corner (exclusive)
+ *
+ * @return EOK on sucess or an error code
+ */
+errno_t console_update(console_ctrl_t *ctrl, sysarg_t c0, sysarg_t r0,
+    sysarg_t c1, sysarg_t r1)
+{
+        async_exch_t *exch = async_exchange_begin(ctrl->output_sess);
+        errno_t rc = async_req_4_0(exch, CONSOLE_UPDATE, c0, r0, c1, r1);
+        async_exchange_end(exch);
+
+        return rc;
+}
+
 /** @}
  */

uspace/lib/c/include/io/con_srv.h

@@ -1 +1 @@
 /*
- * Copyright (c) 2012 Jiri Svoboda
+ * Copyright (c) 2021 Jiri Svoboda
  * All rights reserved.
  *
@@ -39 +39 @@
 #include <async.h>
 #include <fibril_synch.h>
+#include <io/charfield.h>
 #include <io/color.h>
 #include <io/concaps.h>
@@ -83 +84 @@
         void (*set_cursor_visibility)(con_srv_t *, bool);
         errno_t (*get_event)(con_srv_t *, cons_event_t *);
+        errno_t (*map)(con_srv_t *, sysarg_t, sysarg_t, charfield_t **);
+        void (*unmap)(con_srv_t *);
+        void (*update)(con_srv_t *, sysarg_t, sysarg_t, sysarg_t, sysarg_t);
 };
 

uspace/lib/c/include/io/console.h

@@ -1 +1 @@
 /*
- * Copyright (c) 2008 Jiri Svoboda
+ * Copyright (c) 2021 Jiri Svoboda
  * All rights reserved.
  *
@@ -37 +37 @@
 
 #include <time.h>
+#include <io/charfield.h>
 #include <io/concaps.h>
 #include <io/kbd_event.h>
@@ -86 +87 @@
 extern bool console_get_event_timeout(console_ctrl_t *, cons_event_t *,
     usec_t *);
+extern errno_t console_map(console_ctrl_t *, sysarg_t, sysarg_t,
+    charfield_t **);
+extern void console_unmap(console_ctrl_t *, charfield_t *);
+extern errno_t console_update(console_ctrl_t *, sysarg_t, sysarg_t, sysarg_t,
+    sysarg_t);
 
 #endif

uspace/lib/c/include/ipc/console.h

@@ -1 +1 @@
 /*
+ * Copyright (c) 2021 Jiri Svoboda
  * Copyright (c) 2006 Josef Cejka
  * All rights reserved.
@@ -48 +49 @@
         CONSOLE_SET_COLOR,
         CONSOLE_SET_RGB_COLOR,
-        CONSOLE_SET_CURSOR_VISIBILITY
+        CONSOLE_SET_CURSOR_VISIBILITY,
+        CONSOLE_MAP,
+        CONSOLE_UNMAP,
+        CONSOLE_UPDATE
 } console_request_t;
 

uspace/lib/congfx/private/console.h

@@ -1 +1 @@
 /*
- * Copyright (c) 2019 Jiri Svoboda
+ * Copyright (c) 2021 Jiri Svoboda
  * All rights reserved.
  *
@@ -39 +39 @@
 
 #include <gfx/context.h>
+#include <io/charfield.h>
 #include <io/console.h>
 #include <io/pixel.h>
@@ -58 +59 @@
         /** Current drawing color */
         pixel_t clr;
+        /** Shared console buffer */
+        charfield_t *buf;
 };
 

uspace/lib/congfx/src/console.c

@@ -1 +1 @@
 /*
- * Copyright (c) 2019 Jiri Svoboda
+ * Copyright (c) 2021 Jiri Svoboda
  * All rights reserved.
  *
@@ -92 +92 @@
 {
         console_gc_t *cgc = (console_gc_t *) arg;
-        int rv;
         gfx_coord_t x, y;
-
-        // XXX We should handle p0.x > p1.x and p0.y > p1.y
-
-        console_set_rgb_color(cgc->con, cgc->clr, cgc->clr);
-
-        for (y = rect->p0.y; y < rect->p1.y; y++) {
-                console_set_pos(cgc->con, rect->p0.x, y);
-
-                for (x = rect->p0.x; x < rect->p1.x; x++) {
-                        rv = fputc('X', cgc->fout);
-                        if (rv < 0)
-                                return EIO;
-                }
-
-                console_flush(cgc->con);
-        }
+        gfx_coord_t cols;
+        gfx_rect_t crect;
+        charfield_t ch;
+
+        /* Make sure rectangle is clipped and sorted */
+        gfx_rect_clip(rect, &cgc->rect, &crect);
+
+        cols = cgc->rect.p1.x - cgc->rect.p0.x;
+
+        ch.ch = 0;
+        ch.flags = CHAR_FLAG_DIRTY;
+        ch.attrs.type = CHAR_ATTR_RGB;
+        ch.attrs.val.rgb.fgcolor = cgc->clr;
+        ch.attrs.val.rgb.bgcolor = cgc->clr;
+
+        for (y = crect.p0.y; y < crect.p1.y; y++) {
+                for (x = crect.p0.x; x < crect.p1.x; x++) {
+                        cgc->buf[y * cols + x] = ch;
+                }
+        }
+
+        console_update(cgc->con, crect.p0.x, crect.p0.y,
+            crect.p1.x, crect.p1.y);
 
         return EOK;
@@ -131 +137 @@
         sysarg_t rows;
         sysarg_t cols;
+        charfield_t *buf;
         errno_t rc;
 
@@ -140 +147 @@
 
         rc = console_get_size(con, &cols, &rows);
+        if (rc != EOK)
+                goto error;
+
+        rc = console_map(con, cols, rows, &buf);
         if (rc != EOK)
                 goto error;
@@ -154 +165 @@
         cgc->rect.p1.x = cols;
         cgc->rect.p1.y = rows - 1; /* make sure we avoid bottom-right corner */
+        cgc->buf = buf;
 
         *rgc = cgc;
@@ -268 +280 @@
         console_gc_bitmap_t *cbm = (console_gc_bitmap_t *)bm;
         gfx_coord_t x, y;
-        int rv;
         pixel_t clr;
+        charfield_t ch;
         pixelmap_t pixelmap;
         gfx_rect_t srect;
@@ -275 +287 @@
         gfx_rect_t crect;
         gfx_coord2_t offs;
+        gfx_coord_t cols;
 
         if (srect0 != NULL)
@@ -295 +308 @@
         pixelmap.data = cbm->alloc.pixels;
 
+        cols = cbm->cgc->rect.p1.x - cbm->cgc->rect.p0.x;
+
         if ((cbm->flags & bmpf_color_key) == 0) {
                 /* Simple copy */
@@ -304 +319 @@
                                     x - offs.x - cbm->rect.p0.x,
                                     y - offs.y - cbm->rect.p0.y);
-                                console_set_rgb_color(cbm->cgc->con, clr, clr);
-
-                                rv = fputc('X', cbm->cgc->fout);
-                                if (rv < 0)
-                                        return EIO;
-
-                                console_flush(cbm->cgc->con);
+
+                                ch.ch = 0;
+                                ch.flags = CHAR_FLAG_DIRTY;
+                                ch.attrs.type = CHAR_ATTR_RGB;
+                                ch.attrs.val.rgb.fgcolor = clr;
+                                ch.attrs.val.rgb.bgcolor = clr;
+
+                                cbm->cgc->buf[y * cols + x] = ch;
                         }
                 }
@@ -321 +337 @@
                                     x - offs.x - cbm->rect.p0.x,
                                     y - offs.y - cbm->rect.p0.y);
-                                console_set_rgb_color(cbm->cgc->con, clr, clr);
-
-                                if (clr != cbm->key_color) {
-                                        console_set_pos(cbm->cgc->con, x, y);
-                                        rv = fputc('X', cbm->cgc->fout);
-                                        if (rv < 0)
-                                                return EIO;
-
-                                        console_flush(cbm->cgc->con);
-                                }
-
+
+                                ch.ch = 0;
+                                ch.flags = CHAR_FLAG_DIRTY;
+                                ch.attrs.type = CHAR_ATTR_RGB;
+                                ch.attrs.val.rgb.fgcolor = clr;
+                                ch.attrs.val.rgb.bgcolor = clr;
+
+                                if (clr != cbm->key_color)
+                                        cbm->cgc->buf[y * cols + x] = ch;
                         }
                 }
@@ -338 +352 @@
                 console_set_rgb_color(cbm->cgc->con, cbm->cgc->clr,
                     cbm->cgc->clr);
+                ch.ch = 0;
+                ch.flags = CHAR_FLAG_DIRTY;
+                ch.attrs.type = CHAR_ATTR_RGB;
+                ch.attrs.val.rgb.fgcolor = cbm->cgc->clr;
+                ch.attrs.val.rgb.bgcolor = cbm->cgc->clr;
 
                 for (y = crect.p0.y; y < crect.p1.y; y++) {
                         for (x = crect.p0.x; x < crect.p1.x; x++) {
-
                                 clr = pixelmap_get_pixel(&pixelmap,
                                     x - offs.x - cbm->rect.p0.x,
                                     y - offs.y - cbm->rect.p0.y);
 
-                                if (clr != cbm->key_color) {
-                                        console_set_pos(cbm->cgc->con, x, y);
-                                        rv = fputc('X', cbm->cgc->fout);
-                                        if (rv < 0)
-                                                return EIO;
-
-                                        console_flush(cbm->cgc->con);
-                                }
-
+                                if (clr != cbm->key_color)
+                                        cbm->cgc->buf[y * cols + x] = ch;
                         }
                 }
         }
+
+        console_update(cbm->cgc->con, crect.p0.x, crect.p0.y, crect.p1.x,
+            crect.p1.y);
 
         return EOK;

uspace/srv/hid/console/console.c

@@ -1 +1 @@
 /*
+ * Copyright (c) 2021 Jiri Svoboda
  * Copyright (c) 2011 Martin Decky
  * All rights reserved.
@@ -79 +80 @@
         console_caps_t ccaps;  /**< Console capabilities */
 
+        sysarg_t ucols;         /**< Number of columns in user buffer */
+        sysarg_t urows;         /**< Number of rows in user buffer */
+        charfield_t *ubuf;      /**< User buffer */
+
         chargrid_t *frontbuf;    /**< Front buffer */
         frontbuf_handle_t fbid;  /**< Front buffer handle */
@@ -135 +140 @@
 static void cons_set_cursor_visibility(con_srv_t *, bool);
 static errno_t cons_get_event(con_srv_t *, cons_event_t *);
+static errno_t cons_map(con_srv_t *, sysarg_t, sysarg_t, charfield_t **);
+static void cons_unmap(con_srv_t *);
+static void cons_buf_update(con_srv_t *, sysarg_t, sysarg_t, sysarg_t,
+    sysarg_t);
 
 static con_ops_t con_ops = {
@@ -151 +160 @@
         .set_rgb_color = cons_set_rgb_color,
         .set_cursor_visibility = cons_set_cursor_visibility,
-        .get_event = cons_get_event
+        .get_event = cons_get_event,
+        .map = cons_map,
+        .unmap = cons_unmap,
+        .update = cons_buf_update
 };
 
@@ -508 +520 @@
 }
 
+/** Create shared buffer for efficient rendering.
+ *
+ * @param srv Console server
+ * @param cols Number of columns in buffer
+ * @param rows Number of rows in buffer
+ * @param rbuf Place to store pointer to new sharable buffer
+ *
+ * @return EOK on sucess or an error code
+ */
+static errno_t cons_map(con_srv_t *srv, sysarg_t cols, sysarg_t rows,
+    charfield_t **rbuf)
+{
+        console_t *cons = srv_to_console(srv);
+        void *buf;
+
+        fibril_mutex_lock(&cons->mtx);
+
+        if (cons->ubuf != NULL) {
+                fibril_mutex_unlock(&cons->mtx);
+                return EBUSY;
+        }
+
+        buf = as_area_create(AS_AREA_ANY, cols * rows * sizeof(charfield_t),
+            AS_AREA_READ | AS_AREA_WRITE | AS_AREA_CACHEABLE, AS_AREA_UNPAGED);
+        if (buf == AS_MAP_FAILED) {
+                fibril_mutex_unlock(&cons->mtx);
+                return ENOMEM;
+        }
+
+        cons->ucols = cols;
+        cons->urows = rows;
+        cons->ubuf = buf;
+        fibril_mutex_unlock(&cons->mtx);
+
+        *rbuf = buf;
+        return EOK;
+}
+
+/** Delete shared buffer.
+ *
+ * @param srv Console server
+ */
+static void cons_unmap(con_srv_t *srv)
+{
+        console_t *cons = srv_to_console(srv);
+        void *buf;
+
+        fibril_mutex_lock(&cons->mtx);
+
+        buf = cons->ubuf;
+        cons->ubuf = NULL;
+
+        if (buf != NULL)
+                as_area_destroy(buf);
+
+        fibril_mutex_unlock(&cons->mtx);
+}
+
+/** Update area of console from shared buffer.
+ *
+ * @param srv Console server
+ * @param c0 Column coordinate of top-left corner (inclusive)
+ * @param r0 Row coordinate of top-left corner (inclusive)
+ * @param c1 Column coordinate of bottom-right corner (exclusive)
+ * @param r1 Row coordinate of bottom-right corner (exclusive)
+ */
+static void cons_buf_update(con_srv_t *srv, sysarg_t c0, sysarg_t r0,
+    sysarg_t c1, sysarg_t r1)
+{
+        console_t *cons = srv_to_console(srv);
+        charfield_t *ch;
+        sysarg_t col, row;
+
+        fibril_mutex_lock(&cons->mtx);
+
+        if (cons->ubuf == NULL) {
+                fibril_mutex_unlock(&cons->mtx);
+                return;
+        }
+
+        /* Make sure we have meaningful coordinates, within bounds */
+
+        if (c1 > cons->ucols)
+                c1 = cons->ucols;
+        if (c1 > cons->cols)
+                c1 = cons->cols;
+        if (c0 >= c1) {
+                fibril_mutex_unlock(&cons->mtx);
+                return;
+        }
+        if (r1 > cons->urows)
+                r1 = cons->urows;
+        if (r1 > cons->rows)
+                r1 = cons->rows;
+        if (r0 >= r1) {
+                fibril_mutex_unlock(&cons->mtx);
+                return;
+        }
+
+        /* Update front buffer from user buffer */
+
+        for (row = r0; row < r1; row++) {
+                for (col = c0; col < c1; col++) {
+                        ch = chargrid_charfield_at(cons->frontbuf, col, row);
+                        *ch = cons->ubuf[row * cons->ucols + col];
+                }
+        }
+
+        fibril_mutex_unlock(&cons->mtx);
+
+        /* Update console */
+        cons_update(cons);
+}
+
 static void client_connection(ipc_call_t *icall, void *arg)
 {