From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?UTF-8?q?Manuel=20Sch=C3=B6lling?= Date: Fri, 30 May 2014 13:27:05 +0000 Subject: [PATCH] console: Add persistent scrollback buffers for all VGA consoles Message-Id: <1401456425-15931-1-git-send-email-manuel.schoelling@gmx.de> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable To: plagnioj@jcrosoft.com Cc: tomi.valkeinen@ti.com, geert@linux-m68k.org, broonie@linaro.org, rdunlap@infradead.org, dh.herrmann@gmail.com, airlied@redhat.com, mtosatti@redhat.com, linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org, =?UTF-8?q?Manuel=20Sch=C3=B6lling?= Add a scrollback buffers for each VGA console. The benefit is that the scrollback history is not flushed when switching between consoles but is persistent. The buffers are allocated on demand when a new console is opened. Signed-off-by: Manuel Sch=C3=B6lling --- drivers/video/console/Kconfig | 6 +- drivers/video/console/vgacon.c | 124 ++++++++++++++++++++++++------------= ---- 2 files changed, 79 insertions(+), 51 deletions(-) diff --git a/drivers/video/console/Kconfig b/drivers/video/console/Kconfig index fe1cd01..d7ec96c 100644 --- a/drivers/video/console/Kconfig +++ b/drivers/video/console/Kconfig @@ -38,14 +38,14 @@ config VGACON_SOFT_SCROLLBACK RAM to allocate for this buffer. If unsure, say 'N'. =20 config VGACON_SOFT_SCROLLBACK_SIZE - int "Scrollback Buffer Size (in KB)" + int "Scrollback Buffer Size per console (in KB)" depends on VGACON_SOFT_SCROLLBACK range 1 1024 default "64" help Enter the amount of System RAM to allocate for the scrollback - buffer. Each 64KB will give you approximately 16 80x25 - screenfuls of scrollback buffer + buffer for each VGA console. Each 64KB will give you approximately + 16 80x25 screenfuls of scrollback buffer. =20 config MDA_CONSOLE depends on !M68K && !PARISC && ISA diff --git a/drivers/video/console/vgacon.c b/drivers/video/console/vgacon.c index 9d8feac..215eafb 100644 --- a/drivers/video/console/vgacon.c +++ b/drivers/video/console/vgacon.c @@ -181,75 +181,101 @@ static inline void vga_set_mem_top(struct vc_data *c) =20 #ifdef CONFIG_VGACON_SOFT_SCROLLBACK /* software scrollback */ -static void *vgacon_scrollback; -static int vgacon_scrollback_tail; -static int vgacon_scrollback_size; -static int vgacon_scrollback_rows; -static int vgacon_scrollback_cnt; -static int vgacon_scrollback_cur; -static int vgacon_scrollback_save; -static int vgacon_scrollback_restore; - -static void vgacon_scrollback_init(int pitch) +struct vgacon_scrollback_info { + void *data; + int tail; + int size; + int rows; + int cnt; + int cur; + int save; + int restore; +} vgacon_scrollbacks[MAX_NR_CONSOLES]; + +static void vgacon_scrollback_init(int vc_num) { + int pitch =3D vga_video_num_columns * 2; int rows =3D CONFIG_VGACON_SOFT_SCROLLBACK_SIZE * 1024/pitch; + void *data; =20 - if (vgacon_scrollback) { - vgacon_scrollback_cnt =3D 0; - vgacon_scrollback_tail =3D 0; - vgacon_scrollback_cur =3D 0; - vgacon_scrollback_rows =3D rows - 1; - vgacon_scrollback_size =3D rows * pitch; + data =3D kcalloc(CONFIG_VGACON_SOFT_SCROLLBACK_SIZE, 1024, GFP_NOWAIT); + if (!data) { + pr_warn("VGAcon: failed to allocate memory for scrollback.\n"); + vgacon_scrollbacks[vc_num].data =3D NULL; + return; } + + vgacon_scrollbacks[vc_num].data =3D data; + vgacon_scrollbacks[vc_num].cnt =3D 0; + vgacon_scrollbacks[vc_num].tail =3D 0; + vgacon_scrollbacks[vc_num].cur =3D 0; + vgacon_scrollbacks[vc_num].rows =3D rows - 1; + vgacon_scrollbacks[vc_num].size =3D rows * pitch; +} + +static void vgacon_switch_scrollback(int vc_num) +{ + if (!vgacon_scrollbacks[vc_num].data) + vgacon_scrollback_init(vc_num); } =20 static void vgacon_scrollback_startup(void) { - vgacon_scrollback =3D kcalloc(CONFIG_VGACON_SOFT_SCROLLBACK_SIZE, 1024, G= FP_NOWAIT); - vgacon_scrollback_init(vga_video_num_columns * 2); + int i; + + for (i =3D 0; i < MAX_NR_CONSOLES; ++i) + vgacon_scrollbacks[i].data =3D NULL; + + vgacon_scrollback_init(0); } =20 static void vgacon_scrollback_update(struct vc_data *c, int t, int count) { + struct vgacon_scrollback_info *scrollback; void *p; =20 - if (!vgacon_scrollback_size || c->vc_num !=3D fg_console) + scrollback =3D &vgacon_scrollbacks[c->vc_num]; + if (!scrollback->data || !scrollback->size) return; =20 p =3D (void *) (c->vc_origin + t * c->vc_size_row); =20 while (count--) { - scr_memcpyw(vgacon_scrollback + vgacon_scrollback_tail, + scr_memcpyw(scrollback->data + scrollback->tail, p, c->vc_size_row); - vgacon_scrollback_cnt++; + scrollback->cnt++; p +=3D c->vc_size_row; - vgacon_scrollback_tail +=3D c->vc_size_row; + scrollback->tail +=3D c->vc_size_row; =20 - if (vgacon_scrollback_tail >=3D vgacon_scrollback_size) - vgacon_scrollback_tail =3D 0; + if (scrollback->tail >=3D scrollback->size) + scrollback->tail =3D 0; =20 - if (vgacon_scrollback_cnt > vgacon_scrollback_rows) - vgacon_scrollback_cnt =3D vgacon_scrollback_rows; + if (scrollback->cnt > scrollback->rows) + scrollback->cnt =3D scrollback->rows; =20 - vgacon_scrollback_cur =3D vgacon_scrollback_cnt; + scrollback->cur =3D scrollback->cnt; } } =20 static void vgacon_restore_screen(struct vc_data *c) { - vgacon_scrollback_save =3D 0; + struct vgacon_scrollback_info *scrollback; + + scrollback =3D &vgacon_scrollbacks[c->vc_num]; + scrollback->save =3D 0; =20 - if (!vga_is_gfx && !vgacon_scrollback_restore) { + if (!vga_is_gfx && !scrollback->restore) { scr_memcpyw((u16 *) c->vc_origin, (u16 *) c->vc_screenbuf, c->vc_screenbuf_size > vga_vram_size ? vga_vram_size : c->vc_screenbuf_size); - vgacon_scrollback_restore =3D 1; - vgacon_scrollback_cur =3D vgacon_scrollback_cnt; + scrollback->restore =3D 1; + scrollback->cur =3D scrollback->cnt; } } =20 static int vgacon_scrolldelta(struct vc_data *c, int lines) { + struct vgacon_scrollback_info *scrollback; int start, end, count, soff; =20 if (!lines) { @@ -258,41 +284,42 @@ static int vgacon_scrolldelta(struct vc_data *c, int = lines) return 1; } =20 - if (!vgacon_scrollback) + scrollback =3D &vgacon_scrollbacks[c->vc_num]; + if (!scrollback->data) return 1; =20 - if (!vgacon_scrollback_save) { + if (!scrollback->save) { vgacon_cursor(c, CM_ERASE); vgacon_save_screen(c); - vgacon_scrollback_save =3D 1; + scrollback->save =3D 1; } =20 - vgacon_scrollback_restore =3D 0; - start =3D vgacon_scrollback_cur + lines; + scrollback->restore =3D 0; + start =3D scrollback->cur + lines; end =3D start + abs(lines); =20 if (start < 0) start =3D 0; =20 - if (start > vgacon_scrollback_cnt) - start =3D vgacon_scrollback_cnt; + if (start > scrollback->cnt) + start =3D scrollback->cnt; =20 if (end < 0) end =3D 0; =20 - if (end > vgacon_scrollback_cnt) - end =3D vgacon_scrollback_cnt; + if (end > scrollback->cnt) + end =3D scrollback->cnt; =20 - vgacon_scrollback_cur =3D start; + scrollback->cur =3D start; count =3D end - start; - soff =3D vgacon_scrollback_tail - ((vgacon_scrollback_cnt - end) * + soff =3D scrollback->tail - ((scrollback->cnt - end) * c->vc_size_row); soff -=3D count * c->vc_size_row; =20 if (soff < 0) - soff +=3D vgacon_scrollback_size; + soff +=3D scrollback->size; =20 - count =3D vgacon_scrollback_cnt - start; + count =3D scrollback->cnt - start; =20 if (count > c->vc_rows) count =3D c->vc_rows; @@ -306,13 +333,13 @@ static int vgacon_scrolldelta(struct vc_data *c, int = lines) =20 count *=3D c->vc_size_row; /* how much memory to end of buffer left? */ - copysize =3D min(count, vgacon_scrollback_size - soff); - scr_memcpyw(d, vgacon_scrollback + soff, copysize); + copysize =3D min(count, scrollback->size - soff); + scr_memcpyw(d, scrollback->data + soff, copysize); d +=3D copysize; count -=3D copysize; =20 if (count) { - scr_memcpyw(d, vgacon_scrollback, count); + scr_memcpyw(d, scrollback->data, count); d +=3D count; } =20 @@ -327,6 +354,7 @@ static int vgacon_scrolldelta(struct vc_data *c, int li= nes) #define vgacon_scrollback_startup(...) do { } while (0) #define vgacon_scrollback_init(...) do { } while (0) #define vgacon_scrollback_update(...) do { } while (0) +#define vgacon_switch_scrollback(...) do { } while (0) =20 static void vgacon_restore_screen(struct vc_data *c) { @@ -842,7 +870,7 @@ static int vgacon_switch(struct vc_data *c) vgacon_doresize(c, c->vc_cols, c->vc_rows); } =20 - vgacon_scrollback_init(c->vc_size_row); + vgacon_switch_scrollback(c->vc_num); return 0; /* Redrawing not needed */ } =20 --=20 1.7.10.4