[Patch, RFC] Make struct fb_info ref-counted with kref
From: Bruno PrÃmont
Date: Sun Sep 19 2010 - 11:29:54 EST
For USB-attached (or other hot-(un)pluggable) framebuffers the current
fbdev infrastructure is not very helpful. Each such driver currently
needs to perform the ref-counting on its own in .fbops.fb_open and
.fbops.fb_release callbacks.
This patch moves the ref-counting in fbdev infrastructure.
(drivers have not been adjusted, all those releasing fb_info in
.fbops.fb_destroy will not work -- patch for those will follow
later on, all the others will continue to work fine)
API-wise the following changes are done:
- num_registered_fb and registered_fb variables are no more exported.
New functions fb_get_registered() and fb_is_registered() replace
them.
The only know user of those was fbcon, thus the large diff on fbcon.c
Note: the accesses to registered_fb and num_registered_fb look racy
as there was not protection at all around them, potentially letting
register_framebuffer() register two framebuffers on the same minor
concurrently, fbcon access should have been safe by combination of
its use of console_semaphore and reaction to events.
In this patch I combined most of fbcon's accesses to registered_fb
and num_registered_fb into fb_is_registered(), though I'm not sure
if the num-check optimization is worth to keep or its check should
be put into a separate function.
- framebuffer_release() is mapped to fb_put() but will go away
when converting drivers
Reference count for fb_info can be increased with fb_get(fb_info) and
later released with fb_put(fb_info).
If you have concerns regarding the API changes, please let me know.
Thanks,
Bruno
drivers/video/console/fbcon.c | 285 ++++++++++++++++++++++++++---------------
drivers/video/fbmem.c | 254 +++++++++++++++++++++++++++----------
drivers/video/fbsysfs.c | 10 +-
include/linux/fb.h | 20 +++-
4 files changed, 396 insertions(+), 173 deletions(-)
diff --git a/drivers/video/console/fbcon.c b/drivers/video/console/fbcon.c
index 84f8423..011ef4c 100644
--- a/drivers/video/console/fbcon.c
+++ b/drivers/video/console/fbcon.c
@@ -211,14 +211,11 @@ static inline void fbcon_set_rotation(struct fb_info *info)
static void fbcon_rotate(struct fb_info *info, u32 rotate)
{
struct fbcon_ops *ops= info->fbcon_par;
- struct fb_info *fb_info;
if (!ops || ops->currcon == -1)
return;
- fb_info = registered_fb[con2fb_map[ops->currcon]];
-
- if (info == fb_info) {
+ if (fb_is_registered(info, con2fb_map[ops->currcon])) {
struct display *p = &fb_display[ops->currcon];
if (rotate < 4)
@@ -241,9 +238,11 @@ static void fbcon_rotate_all(struct fb_info *info, u32 rotate)
return;
for (i = first_fb_vc; i <= last_fb_vc; i++) {
+ struct fb_info *fb_info;
vc = vc_cons[i].d;
- if (!vc || vc->vc_mode != KD_TEXT ||
- registered_fb[con2fb_map[i]] != info)
+ if (!vc || vc->vc_mode != KD_TEXT)
+ continue;
+ if (!fb_is_registered(info, con2fb_map[i]))
continue;
p = &fb_display[vc->vc_num];
@@ -380,7 +379,7 @@ static void fb_flashcursor(struct work_struct *work)
vc = vc_cons[ops->currcon].d;
if (!vc || !CON_IS_VISIBLE(vc) ||
- registered_fb[con2fb_map[vc->vc_num]] != info ||
+ !fb_is_registered(info, con2fb_map[vc->vc_num]) ||
vc->vc_deccm != 1) {
release_console_sem();
return;
@@ -529,7 +528,7 @@ static int fbcon_takeover(int show_logo)
{
int err, i;
- if (!num_registered_fb)
+ if (!fb_is_registered(NULL, -1))
return -ENODEV;
if (!show_logo)
@@ -793,11 +792,12 @@ static void con2fb_init_display(struct vc_data *vc, struct fb_info *info,
if (show_logo) {
struct vc_data *fg_vc = vc_cons[fg_console].d;
struct fb_info *fg_info =
- registered_fb[con2fb_map[fg_console]];
+ fb_get_registered(con2fb_map[fg_console]);
fbcon_prepare_logo(fg_vc, fg_info, fg_vc->vc_cols,
fg_vc->vc_rows, fg_vc->vc_cols,
fg_vc->vc_rows);
+ fb_put(fg_info);
}
update_screen(vc_cons[fg_console].d);
@@ -816,23 +816,24 @@ static int set_con2fb_map(int unit, int newidx, int user)
{
struct vc_data *vc = vc_cons[unit].d;
int oldidx = con2fb_map[unit];
- struct fb_info *info = registered_fb[newidx];
- struct fb_info *oldinfo = NULL;
+ struct fb_info *info, *oldinfo = NULL;
int found, err = 0;
if (oldidx == newidx)
return 0;
- if (!info || fbcon_has_exited)
+ info = fbcon_has_exited ? NULL : fb_get_registered(newidx);
+ if (!info)
return -EINVAL;
if (!err && !search_for_mapped_con()) {
info_idx = newidx;
+ fb_put(info);
return fbcon_takeover(0);
}
if (oldidx != -1)
- oldinfo = registered_fb[oldidx];
+ oldinfo = fb_get_registered(oldidx);
found = search_fb_in_map(newidx);
@@ -864,6 +865,8 @@ static int set_con2fb_map(int unit, int newidx, int user)
info_idx = newidx;
release_console_sem();
+ fb_put(oldinfo);
+ fb_put(info);
return err;
}
@@ -926,30 +929,34 @@ static const char *fbcon_startup(void)
int rows, cols;
/*
- * If num_registered_fb is zero, this is a call for the dummy part.
- * The frame buffer devices weren't initialized yet.
+ * If fb_is_registered(NULL, -1) returns zero, this is a call for the
+ * dummy part. The frame buffer devices weren't initialized yet.
*/
- if (!num_registered_fb || info_idx == -1)
+ if (!fb_is_registered(NULL, -1) || info_idx == -1)
return display_desc;
/*
- * Instead of blindly using registered_fb[0], we use info_idx, set by
+ * Instead of blindly using minor 0, we use info_idx, set by
* fb_console_init();
*/
- info = registered_fb[info_idx];
+ info = fb_get_registered(info_idx);
if (!info)
return NULL;
owner = info->fbops->owner;
- if (!try_module_get(owner))
+ if (!try_module_get(owner)) {
+ fb_put(info);
return NULL;
+ }
if (info->fbops->fb_open && info->fbops->fb_open(info, 0)) {
module_put(owner);
+ fb_put(info);
return NULL;
}
ops = kzalloc(sizeof(struct fbcon_ops), GFP_KERNEL);
if (!ops) {
module_put(owner);
+ fb_put(info);
return NULL;
}
@@ -1012,12 +1019,13 @@ static const char *fbcon_startup(void)
fbcon_add_cursor_timer(info);
fbcon_has_exited = 0;
+ fb_put(info);
return display_desc;
}
static void fbcon_init(struct vc_data *vc, int init)
{
- struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]];
+ struct fb_info *info = fb_get_registered(con2fb_map[vc->vc_num]);
struct fbcon_ops *ops;
struct vc_data **default_mode = vc->vc_display_fg;
struct vc_data *svc = *default_mode;
@@ -1026,7 +1034,7 @@ static void fbcon_init(struct vc_data *vc, int init)
int cap, ret;
if (info_idx == -1 || info == NULL)
- return;
+ goto out;
cap = info->flags;
@@ -1035,7 +1043,7 @@ static void fbcon_init(struct vc_data *vc, int init)
logo = 0;
if (var_to_display(p, &info->var, info))
- return;
+ goto out;
if (!info->fbcon_par)
con2fb_acquire_newinfo(vc, info, vc->vc_num, -1);
@@ -1153,6 +1161,8 @@ static void fbcon_init(struct vc_data *vc, int init)
}
ops->p = &fb_display[fg_console];
+out:
+ fb_put(info);
}
static void fbcon_free_font(struct display *p)
@@ -1166,7 +1176,7 @@ static void fbcon_free_font(struct display *p)
static void fbcon_deinit(struct vc_data *vc)
{
struct display *p = &fb_display[vc->vc_num];
- struct fb_info *info;
+ struct fb_info *info = NULL;
struct fbcon_ops *ops;
int idx;
@@ -1176,7 +1186,7 @@ static void fbcon_deinit(struct vc_data *vc)
if (idx == -1)
goto finished;
- info = registered_fb[idx];
+ info = fb_get_registered(idx);
if (!info)
goto finished;
@@ -1192,6 +1202,7 @@ static void fbcon_deinit(struct vc_data *vc)
ops->flags &= ~FBCON_FLAGS_INIT;
finished:
+ fb_put(info);
if (!con_is_bound(&fb_con))
fbcon_exit();
@@ -1226,17 +1237,17 @@ finished:
static void fbcon_clear(struct vc_data *vc, int sy, int sx, int height,
int width)
{
- struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]];
+ struct fb_info *info = fb_get_registered(con2fb_map[vc->vc_num]);
struct fbcon_ops *ops = info->fbcon_par;
struct display *p = &fb_display[vc->vc_num];
u_int y_break;
if (fbcon_is_inactive(vc, info))
- return;
+ goto out;
if (!height || !width)
- return;
+ goto out;
if (sy < vc->vc_top && vc->vc_top == logo_lines)
vc->vc_top = 0;
@@ -1251,12 +1262,14 @@ static void fbcon_clear(struct vc_data *vc, int sy, int sx, int height,
width);
} else
ops->clear(vc, info, real_y(p, sy), sx, height, width);
+out:
+ fb_put(info);
}
static void fbcon_putcs(struct vc_data *vc, const unsigned short *s,
int count, int ypos, int xpos)
{
- struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]];
+ struct fb_info *info = fb_get_registered(con2fb_map[vc->vc_num]);
struct display *p = &fb_display[vc->vc_num];
struct fbcon_ops *ops = info->fbcon_par;
@@ -1264,6 +1277,7 @@ static void fbcon_putcs(struct vc_data *vc, const unsigned short *s,
ops->putcs(vc, info, s, count, real_y(p, ypos), xpos,
get_color(vc, info, scr_readw(s), 1),
get_color(vc, info, scr_readw(s), 0));
+ fb_put(info);
}
static void fbcon_putc(struct vc_data *vc, int c, int ypos, int xpos)
@@ -1276,22 +1290,23 @@ static void fbcon_putc(struct vc_data *vc, int c, int ypos, int xpos)
static void fbcon_clear_margins(struct vc_data *vc, int bottom_only)
{
- struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]];
+ struct fb_info *info = fb_get_registered(con2fb_map[vc->vc_num]);
struct fbcon_ops *ops = info->fbcon_par;
if (!fbcon_is_inactive(vc, info))
ops->clear_margins(vc, info, bottom_only);
+ fb_put(info);
}
static void fbcon_cursor(struct vc_data *vc, int mode)
{
- struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]];
+ struct fb_info *info = fb_get_registered(con2fb_map[vc->vc_num]);
struct fbcon_ops *ops = info->fbcon_par;
int y;
int c = scr_readw((u16 *) vc->vc_pos);
if (fbcon_is_inactive(vc, info) || vc->vc_deccm != 1)
- return;
+ goto out;
if (vc->vc_cursor_type & 0x10)
fbcon_del_cursor_timer(info);
@@ -1311,6 +1326,8 @@ static void fbcon_cursor(struct vc_data *vc, int mode)
ops->cursor(vc, info, mode, y, get_color(vc, info, c, 1),
get_color(vc, info, c, 0));
vbl_cursor_cnt = CURSOR_DRAW_DELAY;
+out:
+ fb_put(info);
}
static int scrollback_phys_max = 0;
@@ -1387,7 +1404,7 @@ static void fbcon_set_disp(struct fb_info *info, struct fb_var_screeninfo *var,
static __inline__ void ywrap_up(struct vc_data *vc, int count)
{
- struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]];
+ struct fb_info *info = fb_get_registered(con2fb_map[vc->vc_num]);
struct fbcon_ops *ops = info->fbcon_par;
struct display *p = &fb_display[vc->vc_num];
@@ -1402,11 +1419,12 @@ static __inline__ void ywrap_up(struct vc_data *vc, int count)
if (scrollback_max > scrollback_phys_max)
scrollback_max = scrollback_phys_max;
scrollback_current = 0;
+ fb_put(info);
}
static __inline__ void ywrap_down(struct vc_data *vc, int count)
{
- struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]];
+ struct fb_info *info = fb_get_registered(con2fb_map[vc->vc_num]);
struct fbcon_ops *ops = info->fbcon_par;
struct display *p = &fb_display[vc->vc_num];
@@ -1421,11 +1439,12 @@ static __inline__ void ywrap_down(struct vc_data *vc, int count)
if (scrollback_max < 0)
scrollback_max = 0;
scrollback_current = 0;
+ fb_put(info);
}
static __inline__ void ypan_up(struct vc_data *vc, int count)
{
- struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]];
+ struct fb_info *info = fb_get_registered(con2fb_map[vc->vc_num]);
struct display *p = &fb_display[vc->vc_num];
struct fbcon_ops *ops = info->fbcon_par;
@@ -1445,11 +1464,12 @@ static __inline__ void ypan_up(struct vc_data *vc, int count)
if (scrollback_max > scrollback_phys_max)
scrollback_max = scrollback_phys_max;
scrollback_current = 0;
+ fb_put(info);
}
static __inline__ void ypan_up_redraw(struct vc_data *vc, int t, int count)
{
- struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]];
+ struct fb_info *info = fb_get_registered(con2fb_map[vc->vc_num]);
struct fbcon_ops *ops = info->fbcon_par;
struct display *p = &fb_display[vc->vc_num];
@@ -1469,11 +1489,12 @@ static __inline__ void ypan_up_redraw(struct vc_data *vc, int t, int count)
if (scrollback_max > scrollback_phys_max)
scrollback_max = scrollback_phys_max;
scrollback_current = 0;
+ fb_put(info);
}
static __inline__ void ypan_down(struct vc_data *vc, int count)
{
- struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]];
+ struct fb_info *info = fb_get_registered(con2fb_map[vc->vc_num]);
struct display *p = &fb_display[vc->vc_num];
struct fbcon_ops *ops = info->fbcon_par;
@@ -1493,11 +1514,12 @@ static __inline__ void ypan_down(struct vc_data *vc, int count)
if (scrollback_max < 0)
scrollback_max = 0;
scrollback_current = 0;
+ fb_put(info);
}
static __inline__ void ypan_down_redraw(struct vc_data *vc, int t, int count)
{
- struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]];
+ struct fb_info *info = fb_get_registered(con2fb_map[vc->vc_num]);
struct fbcon_ops *ops = info->fbcon_par;
struct display *p = &fb_display[vc->vc_num];
@@ -1517,6 +1539,7 @@ static __inline__ void ypan_down_redraw(struct vc_data *vc, int t, int count)
if (scrollback_max < 0)
scrollback_max = 0;
scrollback_current = 0;
+ fb_put(info);
}
static void fbcon_redraw_softback(struct vc_data *vc, struct display *p,
@@ -1779,12 +1802,14 @@ static inline void fbcon_softback_note(struct vc_data *vc, int t,
static int fbcon_scroll(struct vc_data *vc, int t, int b, int dir,
int count)
{
- struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]];
+ struct fb_info *info = fb_get_registered(con2fb_map[vc->vc_num]);
struct display *p = &fb_display[vc->vc_num];
int scroll_partial = info->flags & FBINFO_PARTIAL_PAN_OK;
- if (fbcon_is_inactive(vc, info))
+ if (fbcon_is_inactive(vc, info)) {
+ fb_put(info);
return -EINVAL;
+ }
fbcon_cursor(vc, CM_ERASE);
@@ -1812,6 +1837,7 @@ static int fbcon_scroll(struct vc_data *vc, int t, int b, int dir,
(b - count)),
vc->vc_video_erase_char,
vc->vc_size_row * count);
+ fb_put(info);
return 1;
break;
@@ -1884,6 +1910,7 @@ static int fbcon_scroll(struct vc_data *vc, int t, int b, int dir,
(b - count)),
vc->vc_video_erase_char,
vc->vc_size_row * count);
+ fb_put(info);
return 1;
}
break;
@@ -1903,6 +1930,7 @@ static int fbcon_scroll(struct vc_data *vc, int t, int b, int dir,
t),
vc->vc_video_erase_char,
vc->vc_size_row * count);
+ fb_put(info);
return 1;
break;
@@ -1973,9 +2001,11 @@ static int fbcon_scroll(struct vc_data *vc, int t, int b, int dir,
t),
vc->vc_video_erase_char,
vc->vc_size_row * count);
+ fb_put(info);
return 1;
}
}
+ fb_put(info);
return 0;
}
@@ -1983,14 +2013,14 @@ static int fbcon_scroll(struct vc_data *vc, int t, int b, int dir,
static void fbcon_bmove(struct vc_data *vc, int sy, int sx, int dy, int dx,
int height, int width)
{
- struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]];
+ struct fb_info *info = fb_get_registered(con2fb_map[vc->vc_num]);
struct display *p = &fb_display[vc->vc_num];
if (fbcon_is_inactive(vc, info))
- return;
+ goto out;
if (!width || !height)
- return;
+ goto out;
/* Split blits that cross physical y_wrap case.
* Pathological case involves 4 blits, better to use recursive
@@ -2001,12 +2031,14 @@ static void fbcon_bmove(struct vc_data *vc, int sy, int sx, int dy, int dx,
*/
fbcon_bmove_rec(vc, p, sy, sx, dy, dx, height, width,
p->vrows - p->yscroll);
+out:
+ fb_put(info);
}
static void fbcon_bmove_rec(struct vc_data *vc, struct display *p, int sy, int sx,
int dy, int dx, int height, int width, u_int y_break)
{
- struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]];
+ struct fb_info *info = fb_get_registered(con2fb_map[vc->vc_num]);
struct fbcon_ops *ops = info->fbcon_par;
u_int b;
@@ -2023,7 +2055,7 @@ static void fbcon_bmove_rec(struct vc_data *vc, struct display *p, int sy, int s
fbcon_bmove_rec(vc, p, sy, sx, dy, dx, b, width,
y_break);
}
- return;
+ goto out;
}
if (dy < y_break && dy + height > y_break) {
@@ -2039,10 +2071,12 @@ static void fbcon_bmove_rec(struct vc_data *vc, struct display *p, int sy, int s
fbcon_bmove_rec(vc, p, sy, sx, dy, dx, b, width,
y_break);
}
- return;
+ goto out;
}
ops->bmove(vc, info, real_y(p, sy), sx, real_y(p, dy), dx,
height, width);
+out:
+ fb_put(info);
}
static void updatescrollmode(struct display *p,
@@ -2095,7 +2129,7 @@ static void updatescrollmode(struct display *p,
static int fbcon_resize(struct vc_data *vc, unsigned int width,
unsigned int height, unsigned int user)
{
- struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]];
+ struct fb_info *info = fb_get_registered(con2fb_map[vc->vc_num]);
struct fbcon_ops *ops = info->fbcon_par;
struct display *p = &fb_display[vc->vc_num];
struct fb_var_screeninfo var = info->var;
@@ -2118,12 +2152,12 @@ static int fbcon_resize(struct vc_data *vc, unsigned int width,
DPRINTK("attempting resize %ix%i\n", var.xres, var.yres);
mode = fb_find_best_mode(&var, &info->modelist);
if (mode == NULL)
- return -EINVAL;
+ goto einval;
display_to_var(&var, p);
fb_videomode_to_var(&var, mode);
if (virt_w > var.xres/virt_fw || virt_h > var.yres/virt_fh)
- return -EINVAL;
+ goto einval;
DPRINTK("resize now %ix%i\n", var.xres, var.yres);
if (CON_IS_VISIBLE(vc)) {
@@ -2135,7 +2169,11 @@ static int fbcon_resize(struct vc_data *vc, unsigned int width,
ops->var = info->var;
}
updatescrollmode(p, info, vc);
+ fb_put(info);
return 0;
+einval:
+ fb_put(info);
+ return -EINVAL;
}
static int fbcon_switch(struct vc_data *vc)
@@ -2146,7 +2184,7 @@ static int fbcon_switch(struct vc_data *vc)
struct fb_var_screeninfo var;
int i, ret, prev_console, charcnt = 256;
- info = registered_fb[con2fb_map[vc->vc_num]];
+ info = fb_get_registered(con2fb_map[vc->vc_num]);
ops = info->fbcon_par;
if (softback_top) {
@@ -2168,7 +2206,7 @@ static int fbcon_switch(struct vc_data *vc)
prev_console = ops->currcon;
if (prev_console != -1)
- old_info = registered_fb[con2fb_map[prev_console]];
+ old_info = fb_get_registered(con2fb_map[prev_console]);
/*
* FIXME: If we have multiple fbdev's loaded, we need to
* update all info->currcon. Perhaps, we can place this
@@ -2178,11 +2216,13 @@ static int fbcon_switch(struct vc_data *vc)
* info->currcon = vc->vc_num;
*/
for (i = 0; i < FB_MAX; i++) {
- if (registered_fb[i] != NULL && registered_fb[i]->fbcon_par) {
- struct fbcon_ops *o = registered_fb[i]->fbcon_par;
+ struct fb_info *fb = fb_get_registered(i);
+ if (fb != NULL && fb->fbcon_par) {
+ struct fbcon_ops *o = fb->fbcon_par;
o->currcon = vc->vc_num;
}
+ fb_put(fb);
}
memset(&var, 0, sizeof(struct fb_var_screeninfo));
display_to_var(&var, p);
@@ -2272,8 +2312,12 @@ static int fbcon_switch(struct vc_data *vc)
vc->vc_origin + vc->vc_size_row * vc->vc_top,
vc->vc_size_row * (vc->vc_bottom -
vc->vc_top) / 2);
+ fb_put(info);
+ fb_put(old_info);
return 0;
}
+ fb_put(info);
+ fb_put(old_info);
return 1;
}
@@ -2304,7 +2348,7 @@ static void fbcon_generic_blank(struct vc_data *vc, struct fb_info *info,
static int fbcon_blank(struct vc_data *vc, int blank, int mode_switch)
{
- struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]];
+ struct fb_info *info = fb_get_registered(con2fb_map[vc->vc_num]);
struct fbcon_ops *ops = info->fbcon_par;
if (mode_switch) {
@@ -2341,12 +2385,13 @@ static int fbcon_blank(struct vc_data *vc, int blank, int mode_switch)
else
fbcon_add_cursor_timer(info);
+ fb_put(info);
return 0;
}
static int fbcon_debug_enter(struct vc_data *vc)
{
- struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]];
+ struct fb_info *info = fb_get_registered(con2fb_map[vc->vc_num]);
struct fbcon_ops *ops = info->fbcon_par;
ops->save_graphics = ops->graphics;
@@ -2354,17 +2399,19 @@ static int fbcon_debug_enter(struct vc_data *vc)
if (info->fbops->fb_debug_enter)
info->fbops->fb_debug_enter(info);
fbcon_set_palette(vc, color_table);
+ fb_put(info);
return 0;
}
static int fbcon_debug_leave(struct vc_data *vc)
{
- struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]];
+ struct fb_info *info = fb_get_registered(con2fb_map[vc->vc_num]);
struct fbcon_ops *ops = info->fbcon_par;
ops->graphics = ops->save_graphics;
if (info->fbops->fb_debug_leave)
info->fbops->fb_debug_leave(info);
+ fb_put(info);
return 0;
}
@@ -2422,7 +2469,7 @@ static int fbcon_get_font(struct vc_data *vc, struct console_font *font)
static int fbcon_do_set_font(struct vc_data *vc, int w, int h,
const u8 * data, int userfont)
{
- struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]];
+ struct fb_info *info = fb_get_registered(con2fb_map[vc->vc_num]);
struct fbcon_ops *ops = info->fbcon_par;
struct display *p = &fb_display[vc->vc_num];
int resize;
@@ -2520,6 +2567,7 @@ static int fbcon_do_set_font(struct vc_data *vc, int w, int h,
if (old_data && (--REFCOUNT(old_data) == 0))
kfree(old_data - FONT_EXTRA_WORDS * sizeof(int));
+ fb_put(info);
return 0;
}
@@ -2547,7 +2595,7 @@ static int fbcon_copy_font(struct vc_data *vc, int con)
static int fbcon_set_font(struct vc_data *vc, struct console_font *font, unsigned flags)
{
- struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]];
+ struct fb_info *info = fb_get_registered(con2fb_map[vc->vc_num]);
unsigned charcount = font->charcount;
int w = font->width;
int h = font->height;
@@ -2558,24 +2606,32 @@ static int fbcon_set_font(struct vc_data *vc, struct console_font *font, unsigne
/* Is there a reason why fbconsole couldn't handle any charcount >256?
* If not this check should be changed to charcount < 256 */
- if (charcount != 256 && charcount != 512)
+ if (charcount != 256 && charcount != 512) {
+ fb_put(info);
return -EINVAL;
+ }
/* Make sure drawing engine can handle the font */
if (!(info->pixmap.blit_x & (1 << (font->width - 1))) ||
- !(info->pixmap.blit_y & (1 << (font->height - 1))))
+ !(info->pixmap.blit_y & (1 << (font->height - 1)))) {
+ fb_put(info);
return -EINVAL;
+ }
/* Make sure driver can handle the font length */
- if (fbcon_invalid_charcount(info, charcount))
+ if (fbcon_invalid_charcount(info, charcount)) {
+ fb_put(info);
return -EINVAL;
+ }
size = h * pitch * charcount;
new_data = kmalloc(FONT_EXTRA_WORDS * sizeof(int) + size, GFP_USER);
- if (!new_data)
+ if (!new_data) {
+ fb_put(info);
return -ENOMEM;
+ }
new_data += FONT_EXTRA_WORDS * sizeof(int);
FNTSIZE(new_data) = size;
@@ -2605,22 +2661,26 @@ static int fbcon_set_font(struct vc_data *vc, struct console_font *font, unsigne
break;
}
}
+ fb_put(info);
return fbcon_do_set_font(vc, font->width, font->height, new_data, 1);
}
static int fbcon_set_def_font(struct vc_data *vc, struct console_font *font, char *name)
{
- struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]];
+ struct fb_info *info = fb_get_registered(con2fb_map[vc->vc_num]);
const struct font_desc *f;
if (!name)
f = get_default_font(info->var.xres, info->var.yres,
info->pixmap.blit_x, info->pixmap.blit_y);
- else if (!(f = find_font(name)))
+ else if (!(f = find_font(name))) {
+ fb_put(info);
return -ENOENT;
+ }
font->width = f->width;
font->height = f->height;
+ fb_put(info);
return fbcon_do_set_font(vc, f->width, f->height, f->data, 0);
}
@@ -2634,15 +2694,19 @@ static struct fb_cmap palette_cmap = {
static int fbcon_set_palette(struct vc_data *vc, unsigned char *table)
{
- struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]];
- int i, j, k, depth;
+ struct fb_info *info = fb_get_registered(con2fb_map[vc->vc_num]);
+ int i, j, k, depth, ret;
u8 val;
- if (fbcon_is_inactive(vc, info))
- return -EINVAL;
+ if (fbcon_is_inactive(vc, info)) {
+ ret = -EINVAL;
+ goto out;
+ }
- if (!CON_IS_VISIBLE(vc))
- return 0;
+ if (!CON_IS_VISIBLE(vc)) {
+ ret = 0;
+ goto out;
+ }
depth = fb_get_color_depth(&info->var, &info->fix);
if (depth > 3) {
@@ -2664,7 +2728,10 @@ static int fbcon_set_palette(struct vc_data *vc, unsigned char *table)
} else
fb_copy_cmap(fb_default_cmap(1 << depth), &palette_cmap);
- return fb_set_cmap(&palette_cmap, info);
+ ret = fb_set_cmap(&palette_cmap, info);
+out:
+ fb_put(info);
+ return ret;
}
static u16 *fbcon_screen_pos(struct vc_data *vc, int offset)
@@ -2747,16 +2814,16 @@ static void fbcon_invert_region(struct vc_data *vc, u16 * p, int cnt)
static int fbcon_scrolldelta(struct vc_data *vc, int lines)
{
- struct fb_info *info = registered_fb[con2fb_map[fg_console]];
+ struct fb_info *info = fb_get_registered(con2fb_map[fg_console]);
struct fbcon_ops *ops = info->fbcon_par;
struct display *disp = &fb_display[fg_console];
- int offset, limit, scrollback_old;
+ int offset, limit, scrollback_old, ret = 0;
if (softback_top) {
if (vc->vc_num != fg_console)
- return 0;
+ goto out;
if (vc->vc_mode != KD_TEXT || !lines)
- return 0;
+ goto out;
if (logo_shown >= 0) {
struct vc_data *conp2 = vc_cons[logo_shown].d;
@@ -2789,11 +2856,13 @@ static int fbcon_scrolldelta(struct vc_data *vc, int lines)
fbcon_cursor(vc, CM_ERASE | CM_SOFTBACK);
fbcon_redraw_softback(vc, disp, lines);
fbcon_cursor(vc, CM_DRAW | CM_SOFTBACK);
- return 0;
+ goto out;
}
- if (!scrollback_phys_max)
- return -ENOSYS;
+ if (!scrollback_phys_max) {
+ ret = -ENOSYS;
+ goto out;
+ }
scrollback_old = scrollback_current;
scrollback_current -= lines;
@@ -2802,10 +2871,10 @@ static int fbcon_scrolldelta(struct vc_data *vc, int lines)
else if (scrollback_current > scrollback_max)
scrollback_current = scrollback_max;
if (scrollback_current == scrollback_old)
- return 0;
+ goto out;
if (fbcon_is_inactive(vc, info))
- return 0;
+ goto out;
fbcon_cursor(vc, CM_ERASE);
@@ -2832,7 +2901,10 @@ static int fbcon_scrolldelta(struct vc_data *vc, int lines)
if (!scrollback_current)
fbcon_cursor(vc, CM_DRAW);
- return 0;
+
+out:
+ fb_put(info);
+ return ret;
}
static int fbcon_set_origin(struct vc_data *vc)
@@ -2878,7 +2950,7 @@ static void fbcon_modechanged(struct fb_info *info)
return;
vc = vc_cons[ops->currcon].d;
if (vc->vc_mode != KD_TEXT ||
- registered_fb[con2fb_map[ops->currcon]] != info)
+ !fb_is_registered(info, con2fb_map[ops->currcon]))
return;
p = &fb_display[vc->vc_num];
@@ -2920,7 +2992,7 @@ static void fbcon_set_all_vcs(struct fb_info *info)
for (i = first_fb_vc; i <= last_fb_vc; i++) {
vc = vc_cons[i].d;
if (!vc || vc->vc_mode != KD_TEXT ||
- registered_fb[con2fb_map[i]] != info)
+ !fb_is_registered(info, con2fb_map[i]))
continue;
if (CON_IS_VISIBLE(vc)) {
@@ -2945,7 +3017,6 @@ static void fbcon_set_all_vcs(struct fb_info *info)
static int fbcon_mode_deleted(struct fb_info *info,
struct fb_videomode *mode)
{
- struct fb_info *fb_info;
struct display *p;
int i, j, found = 0;
@@ -2954,8 +3025,7 @@ static int fbcon_mode_deleted(struct fb_info *info,
j = con2fb_map[i];
if (j == -1)
continue;
- fb_info = registered_fb[j];
- if (fb_info != info)
+ if (!fb_is_registered(info, j))
continue;
p = &fb_display[i];
if (!p || !p->mode)
@@ -3028,7 +3098,9 @@ static int fbcon_fb_unregistered(struct fb_info *info)
info_idx = -1;
for (i = 0; i < FB_MAX; i++) {
- if (registered_fb[i] != NULL) {
+ struct fb_info *fb_info = fb_get_registered(i);
+ fb_put(fb_info);
+ if (fb_info != NULL) {
info_idx = i;
break;
}
@@ -3045,7 +3117,7 @@ static int fbcon_fb_unregistered(struct fb_info *info)
if (primary_device == idx)
primary_device = -1;
- if (!num_registered_fb)
+ if (!fb_is_registered(NULL, -1))
unregister_con_driver(&fb_con);
return 0;
@@ -3132,7 +3204,7 @@ static void fbcon_fb_blanked(struct fb_info *info, int blank)
vc = vc_cons[ops->currcon].d;
if (vc->vc_mode != KD_TEXT ||
- registered_fb[con2fb_map[ops->currcon]] != info)
+ !fb_is_registered(info, con2fb_map[ops->currcon]))
return;
if (CON_IS_VISIBLE(vc)) {
@@ -3152,7 +3224,7 @@ static void fbcon_new_modelist(struct fb_info *info)
const struct fb_videomode *mode;
for (i = first_fb_vc; i <= last_fb_vc; i++) {
- if (registered_fb[con2fb_map[i]] != info)
+ if (!fb_is_registered(info, con2fb_map[i]))
continue;
if (!fb_display[i].mode)
continue;
@@ -3324,12 +3396,13 @@ static ssize_t store_rotate(struct device *device,
acquire_console_sem();
idx = con2fb_map[fg_console];
- if (idx == -1 || registered_fb[idx] == NULL)
+ info = fb_get_registered(idx);
+ if (!info);
goto err;
- info = registered_fb[idx];
rotate = simple_strtoul(buf, last, 0);
fbcon_rotate(info, rotate);
+ fb_put(info);
err:
release_console_sem();
return count;
@@ -3349,12 +3422,13 @@ static ssize_t store_rotate_all(struct device *device,
acquire_console_sem();
idx = con2fb_map[fg_console];
- if (idx == -1 || registered_fb[idx] == NULL)
+ info = fb_get_registered(idx);
+ if (!info)
goto err;
- info = registered_fb[idx];
rotate = simple_strtoul(buf, last, 0);
fbcon_rotate_all(info, rotate);
+ fb_put(info);
err:
release_console_sem();
return count;
@@ -3372,11 +3446,12 @@ static ssize_t show_rotate(struct device *device,
acquire_console_sem();
idx = con2fb_map[fg_console];
- if (idx == -1 || registered_fb[idx] == NULL)
+ info = fb_get_registered(idx);
+ if (!info)
goto err;
- info = registered_fb[idx];
rotate = fbcon_get_rotate(info);
+ fb_put(info);
err:
release_console_sem();
return snprintf(buf, PAGE_SIZE, "%d\n", rotate);
@@ -3395,10 +3470,10 @@ static ssize_t show_cursor_blink(struct device *device,
acquire_console_sem();
idx = con2fb_map[fg_console];
- if (idx == -1 || registered_fb[idx] == NULL)
+ info = fb_get_registered(idx);
+ if (!info)
goto err;
- info = registered_fb[idx];
ops = info->fbcon_par;
if (!ops)
@@ -3406,6 +3481,7 @@ static ssize_t show_cursor_blink(struct device *device,
blink = (ops->flags & FBCON_FLAGS_CURSOR_TIMER) ? 1 : 0;
err:
+ fb_put(info);
release_console_sem();
return snprintf(buf, PAGE_SIZE, "%d\n", blink);
}
@@ -3424,11 +3500,10 @@ static ssize_t store_cursor_blink(struct device *device,
acquire_console_sem();
idx = con2fb_map[fg_console];
- if (idx == -1 || registered_fb[idx] == NULL)
+ info = fb_get_registered(idx);
+ if (!info)
goto err;
- info = registered_fb[idx];
-
if (!info->fbcon_par)
goto err;
@@ -3443,6 +3518,7 @@ static ssize_t store_cursor_blink(struct device *device,
}
err:
+ fb_put(info);
release_console_sem();
return count;
}
@@ -3479,13 +3555,15 @@ static int fbcon_init_device(void)
static void fbcon_start(void)
{
- if (num_registered_fb) {
+ if (fb_is_registered(NULL, -1)) {
int i;
acquire_console_sem();
for (i = 0; i < FB_MAX; i++) {
- if (registered_fb[i] != NULL) {
+ struct fb_info *fb_info = fb_get_registered(i);
+ if (fb_info) {
+ fb_put(fb_info);
info_idx = i;
break;
}
@@ -3511,7 +3589,7 @@ static void fbcon_exit(void)
int pending;
mapped = 0;
- info = registered_fb[i];
+ info = fb_get_registered(i);
if (info == NULL)
continue;
@@ -3542,6 +3620,7 @@ static void fbcon_exit(void)
if (info->queue.func == fb_flashcursor)
info->queue.func = NULL;
}
+ fb_put(info);
}
fbcon_has_exited = 1;
diff --git a/drivers/video/fbmem.c b/drivers/video/fbmem.c
index b066475..eb89523 100644
--- a/drivers/video/fbmem.c
+++ b/drivers/video/fbmem.c
@@ -42,8 +42,60 @@
#define FBPIXMAPSIZE (1024 * 8)
-struct fb_info *registered_fb[FB_MAX] __read_mostly;
-int num_registered_fb __read_mostly;
+static spinlock_t lock_registered_fb = SPIN_LOCK_UNLOCKED;
+static struct fb_info *registered_fb[FB_MAX] __read_mostly;
+static int num_registered_fb __read_mostly;
+
+/**
+ * fb_get_registered - get a reference to framebuffer registered
+ * at @fbidx.
+ *
+ * Note: returns pointer to registered framebuffer with incremented
+ * refcount.
+ */
+struct fb_info *fb_get_registered(int fbidx)
+{
+ unsigned long flags;
+ struct fb_info *ret;
+
+ if (fbidx < 0 || fbidx >= FB_MAX)
+ return NULL;
+ spin_lock_irqsave(&lock_registered_fb, flags);
+ ret = registered_fb[fbidx];
+ if (IS_ERR(ret))
+ ret = NULL;
+ if (ret)
+ kref_get(&ret->refcount);
+ spin_unlock_irqrestore(&lock_registered_fb, flags);
+ return ret;
+}
+
+/**
+ * fb_is_registered - check if a framebuffer is registered
+ *
+ * @fbidx: -1 to check at position fb_info->node, other
+ * make sure framebuffer is registered at mentioned
+ * index
+ * @fb_info: NULL to request count of registered framebuffers,
+ * otherwise framebuffer to verify is registered
+ */
+int fb_is_registered(struct fb_info *fb_info, int fbidx)
+{
+ unsigned long flags;
+ int ret;
+
+ if (fbidx < -1 || fbidx >= FB_MAX)
+ return 0;
+ spin_lock_irqsave(&lock_registered_fb, flags);
+ if (fbidx >= 0)
+ ret = registered_fb[fbidx] == fb_info;
+ else if (!fb_info)
+ ret = num_registered_fb;
+ else
+ ret = registered_fb[fb_info->node] == fb_info;
+ spin_unlock_irqrestore(&lock_registered_fb, flags);
+ return ret;
+}
int lock_fb_info(struct fb_info *info)
{
@@ -663,10 +715,12 @@ static void fb_seq_stop(struct seq_file *m, void *v)
static int fb_seq_show(struct seq_file *m, void *v)
{
int i = *(loff_t *)v;
- struct fb_info *fi = registered_fb[i];
+ struct fb_info *fi = fb_get_registered(i);
- if (fi)
+ if (fi) {
seq_printf(m, "%d %s\n", fi->node, fi->fix.id);
+ fb_put(fi);
+ }
return 0;
}
@@ -696,28 +750,34 @@ fb_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
unsigned long p = *ppos;
struct inode *inode = file->f_path.dentry->d_inode;
int fbidx = iminor(inode);
- struct fb_info *info = registered_fb[fbidx];
+ struct fb_info *info = fb_get_registered(fbidx);
u32 *buffer, *dst;
u32 __iomem *src;
int c, i, cnt = 0, err = 0;
unsigned long total_size;
- if (!info || ! info->screen_base)
- return -ENODEV;
+ if (!info || ! info->screen_base) {
+ err = -ENODEV;
+ goto out;
+ }
+
+ if (info->state != FBINFO_STATE_RUNNING) {
+ err = -EPERM;
+ goto out;
+ }
- if (info->state != FBINFO_STATE_RUNNING)
- return -EPERM;
+ if (info->fbops->fb_read) {
+ cnt = info->fbops->fb_read(info, buf, count, ppos);
+ goto out;
+ }
- if (info->fbops->fb_read)
- return info->fbops->fb_read(info, buf, count, ppos);
-
total_size = info->screen_size;
if (total_size == 0)
total_size = info->fix.smem_len;
if (p >= total_size)
- return 0;
+ goto out;
if (count >= total_size)
count = total_size;
@@ -727,8 +787,10 @@ fb_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
buffer = kmalloc((count > PAGE_SIZE) ? PAGE_SIZE : count,
GFP_KERNEL);
- if (!buffer)
- return -ENOMEM;
+ if (!buffer) {
+ err = -ENOMEM;
+ goto out;
+ }
src = (u32 __iomem *) (info->screen_base + p);
@@ -762,6 +824,9 @@ fb_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
kfree(buffer);
+out:
+ if (info)
+ fb_put(info);
return (err) ? err : cnt;
}
@@ -771,28 +836,36 @@ fb_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
unsigned long p = *ppos;
struct inode *inode = file->f_path.dentry->d_inode;
int fbidx = iminor(inode);
- struct fb_info *info = registered_fb[fbidx];
+ struct fb_info *info = fb_get_registered(fbidx);
u32 *buffer, *src;
u32 __iomem *dst;
int c, i, cnt = 0, err = 0;
unsigned long total_size;
- if (!info || !info->screen_base)
- return -ENODEV;
+ if (!info || !info->screen_base) {
+ err = -ENODEV;
+ goto out;
+ }
- if (info->state != FBINFO_STATE_RUNNING)
- return -EPERM;
+ if (info->state != FBINFO_STATE_RUNNING) {
+ err = -EPERM;
+ goto out;
+ }
- if (info->fbops->fb_write)
- return info->fbops->fb_write(info, buf, count, ppos);
+ if (info->fbops->fb_write) {
+ cnt = info->fbops->fb_write(info, buf, count, ppos);
+ goto out;
+ }
total_size = info->screen_size;
if (total_size == 0)
total_size = info->fix.smem_len;
- if (p > total_size)
- return -EFBIG;
+ if (p > total_size) {
+ err = -EFBIG;
+ goto out;
+ }
if (count > total_size) {
err = -EFBIG;
@@ -808,8 +881,10 @@ fb_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
buffer = kmalloc((count > PAGE_SIZE) ? PAGE_SIZE : count,
GFP_KERNEL);
- if (!buffer)
- return -ENOMEM;
+ if (!buffer) {
+ err = -ENOMEM;
+ goto out;
+ }
dst = (u32 __iomem *) (info->screen_base + p);
@@ -846,6 +921,9 @@ fb_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
kfree(buffer);
+out:
+ if (info)
+ fb_put(info);
return (cnt) ? cnt : err;
}
@@ -1121,6 +1199,7 @@ static long do_fb_ioctl(struct fb_info *info, unsigned int cmd,
return -EINVAL;
if (con2fb.framebuffer < 0 || con2fb.framebuffer >= FB_MAX)
return -EINVAL;
+ /* FIXME: these should never hit as fb_ioctl() looks for info before calling us! */
if (!registered_fb[con2fb.framebuffer])
request_module("fb%d", con2fb.framebuffer);
if (!registered_fb[con2fb.framebuffer]) {
@@ -1161,9 +1240,15 @@ static long fb_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
struct inode *inode = file->f_path.dentry->d_inode;
int fbidx = iminor(inode);
- struct fb_info *info = registered_fb[fbidx];
+ struct fb_info *info = fb_get_registered(fbidx);
+ long ret;
+
+ if (!info)
+ return -ENODEV;
- return do_fb_ioctl(info, cmd, arg);
+ ret = do_fb_ioctl(info, cmd, arg);
+ fb_put(info);
+ return ret;
}
#ifdef CONFIG_COMPAT
@@ -1285,10 +1370,14 @@ static long fb_compat_ioctl(struct file *file, unsigned int cmd,
{
struct inode *inode = file->f_path.dentry->d_inode;
int fbidx = iminor(inode);
- struct fb_info *info = registered_fb[fbidx];
- struct fb_ops *fb = info->fbops;
+ struct fb_info *info = fb_get_registered(fbidx);
+ struct fb_ops *fb;
long ret = -ENOIOCTLCMD;
+ if (!info)
+ return -ENODEV;
+ fb = info->fbops;
+
switch(cmd) {
case FBIOGET_VSCREENINFO:
case FBIOPUT_VSCREENINFO:
@@ -1314,6 +1403,7 @@ static long fb_compat_ioctl(struct file *file, unsigned int cmd,
ret = fb->fb_compat_ioctl(info, cmd, arg);
break;
}
+ fb_put(info);
return ret;
}
#endif
@@ -1322,23 +1412,31 @@ static int
fb_mmap(struct file *file, struct vm_area_struct * vma)
{
int fbidx = iminor(file->f_path.dentry->d_inode);
- struct fb_info *info = registered_fb[fbidx];
- struct fb_ops *fb = info->fbops;
+ struct fb_info *info = fb_get_registered(fbidx);
+ struct fb_ops *fb;
unsigned long off;
unsigned long start;
u32 len;
+ int ret = 0;
- if (vma->vm_pgoff > (~0UL >> PAGE_SHIFT))
- return -EINVAL;
- off = vma->vm_pgoff << PAGE_SHIFT;
- if (!fb)
+ if (!info)
return -ENODEV;
+ fb = info->fbops;
+
+ if (vma->vm_pgoff > (~0UL >> PAGE_SHIFT)) {
+ ret = -EINVAL;
+ goto out;
+ }
+ off = vma->vm_pgoff << PAGE_SHIFT;
+ if (!fb) {
+ ret = -ENODEV;
+ goto out;
+ }
mutex_lock(&info->mm_lock);
if (fb->fb_mmap) {
- int res;
- res = fb->fb_mmap(info, vma);
+ ret = fb->fb_mmap(info, vma);
mutex_unlock(&info->mm_lock);
- return res;
+ goto out;
}
/* frame buffer memory */
@@ -1349,15 +1447,18 @@ fb_mmap(struct file *file, struct vm_area_struct * vma)
off -= len;
if (info->var.accel_flags) {
mutex_unlock(&info->mm_lock);
- return -EINVAL;
+ ret = -EINVAL;
+ goto out;
}
start = info->fix.mmio_start;
len = PAGE_ALIGN((start & ~PAGE_MASK) + info->fix.mmio_len);
}
mutex_unlock(&info->mm_lock);
start &= PAGE_MASK;
- if ((vma->vm_end - vma->vm_start + off) > len)
- return -EINVAL;
+ if ((vma->vm_end - vma->vm_start + off) > len) {
+ ret = -EINVAL;
+ goto out;
+ }
off += start;
vma->vm_pgoff = off >> PAGE_SHIFT;
/* This is an IO map - tell maydump to skip this VMA */
@@ -1365,9 +1466,13 @@ fb_mmap(struct file *file, struct vm_area_struct * vma)
vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
fb_pgprotect(file, vma, off);
if (io_remap_pfn_range(vma, vma->vm_start, off >> PAGE_SHIFT,
- vma->vm_end - vma->vm_start, vma->vm_page_prot))
- return -EAGAIN;
- return 0;
+ vma->vm_end - vma->vm_start, vma->vm_page_prot)) {
+ ret = -EAGAIN;
+ goto out;
+ }
+out:
+ fb_put(info);
+ return ret;
}
static int
@@ -1381,12 +1486,13 @@ __releases(&info->lock)
if (fbidx >= FB_MAX)
return -ENODEV;
- info = registered_fb[fbidx];
- if (!info)
+ info = fb_get_registered(fbidx);
+ if (!info) {
request_module("fb%d", fbidx);
- info = registered_fb[fbidx];
- if (!info)
- return -ENODEV;
+ info = fb_get_registered(fbidx);
+ if (!info)
+ return -ENODEV;
+ }
mutex_lock(&info->lock);
if (!try_module_get(info->fbops->owner)) {
res = -ENODEV;
@@ -1404,6 +1510,8 @@ __releases(&info->lock)
#endif
out:
mutex_unlock(&info->lock);
+ if (res)
+ fb_put(info);
return res;
}
@@ -1419,6 +1527,7 @@ __releases(&info->lock)
info->fbops->fb_release(info,1);
module_put(info->fbops->owner);
mutex_unlock(&info->lock);
+ fb_put(info);
return 0;
}
@@ -1513,22 +1622,25 @@ void remove_conflicting_framebuffers(struct apertures_struct *a,
/* check all firmware fbs and kick off if the base addr overlaps */
for (i = 0 ; i < FB_MAX; i++) {
struct apertures_struct *gen_aper;
- if (!registered_fb[i])
+ struct fb_info *info = fb_get_registered(i);
+ if (!info)
continue;
- if (!(registered_fb[i]->flags & FBINFO_MISC_FIRMWARE))
- continue;
+ if (!(info->flags & FBINFO_MISC_FIRMWARE))
+ goto done;
- gen_aper = registered_fb[i]->apertures;
+ gen_aper = info->apertures;
if (fb_do_apertures_overlap(gen_aper, a) ||
(primary && gen_aper && gen_aper->count &&
gen_aper->ranges[0].base == VGA_FB_PHYS)) {
printk(KERN_ERR "fb: conflicting fb hw usage "
"%s vs %s - removing generic driver\n",
- name, registered_fb[i]->fix.id);
- unregister_framebuffer(registered_fb[i]);
+ name, info->fix.id);
+ unregister_framebuffer(info);
}
+done:
+ fb_put(info);
}
}
EXPORT_SYMBOL(remove_conflicting_framebuffers);
@@ -1549,9 +1661,7 @@ register_framebuffer(struct fb_info *fb_info)
int i;
struct fb_event event;
struct fb_videomode mode;
-
- if (num_registered_fb == FB_MAX)
- return -ENXIO;
+ unsigned long flags;
if (fb_check_foreignness(fb_info))
return -ENOSYS;
@@ -1559,11 +1669,19 @@ register_framebuffer(struct fb_info *fb_info)
remove_conflicting_framebuffers(fb_info->apertures, fb_info->fix.id,
fb_is_primary_device(fb_info));
+ spin_lock_irqsave(&lock_registered_fb, flags);
+ if (num_registered_fb == FB_MAX) {
+ spin_unlock_irqrestore(&lock_registered_fb, flags);
+ return -ENXIO;
+ }
+
num_registered_fb++;
for (i = 0 ; i < FB_MAX; i++)
if (!registered_fb[i])
break;
+ registered_fb[i] = ERR_PTR(-EBUSY);
fb_info->node = i;
+ spin_unlock_irqrestore(&lock_registered_fb, flags);
mutex_init(&fb_info->lock);
mutex_init(&fb_info->mm_lock);
@@ -1599,7 +1717,9 @@ register_framebuffer(struct fb_info *fb_info)
fb_var_to_videomode(&mode, &fb_info->var);
fb_add_videomode(&mode, &fb_info->modelist);
+ spin_lock_irqsave(&lock_registered_fb, flags);
registered_fb[i] = fb_info;
+ spin_unlock_irqrestore(&lock_registered_fb, flags);
event.info = fb_info;
if (!lock_fb_info(fb_info))
@@ -1632,12 +1752,15 @@ unregister_framebuffer(struct fb_info *fb_info)
{
struct fb_event event;
int i, ret = 0;
+ unsigned long flags;
i = fb_info->node;
- if (!registered_fb[i]) {
+ spin_lock_irqsave(&lock_registered_fb, flags);
+ if (registered_fb[i] != fb_info)
ret = -EINVAL;
+ spin_unlock_irqrestore(&lock_registered_fb, flags);
+ if (ret)
goto done;
- }
if (!lock_fb_info(fb_info))
@@ -1655,16 +1778,17 @@ unregister_framebuffer(struct fb_info *fb_info)
(fb_info->pixmap.flags & FB_PIXMAP_DEFAULT))
kfree(fb_info->pixmap.addr);
fb_destroy_modelist(&fb_info->modelist);
+ spin_lock_irqsave(&lock_registered_fb, flags);
registered_fb[i]=NULL;
num_registered_fb--;
+ spin_unlock_irqrestore(&lock_registered_fb, flags);
fb_cleanup_device(fb_info);
device_destroy(fb_class, MKDEV(FB_MAJOR, i));
event.info = fb_info;
fb_notifier_call_chain(FB_EVENT_FB_UNREGISTERED, &event);
/* this may free fb info */
- if (fb_info->fbops->fb_destroy)
- fb_info->fbops->fb_destroy(fb_info);
+ fb_put(fb_info);
done:
return ret;
}
@@ -1864,10 +1988,10 @@ __setup("video=", video_setup);
* Visible symbols for modules
*/
+EXPORT_SYMBOL(fb_get_registered);
+EXPORT_SYMBOL(fb_is_registered);
EXPORT_SYMBOL(register_framebuffer);
EXPORT_SYMBOL(unregister_framebuffer);
-EXPORT_SYMBOL(num_registered_fb);
-EXPORT_SYMBOL(registered_fb);
EXPORT_SYMBOL(fb_show_logo);
EXPORT_SYMBOL(fb_set_var);
EXPORT_SYMBOL(fb_blank);
diff --git a/drivers/video/fbsysfs.c b/drivers/video/fbsysfs.c
index 0a08f13..be5f342 100644
--- a/drivers/video/fbsysfs.c
+++ b/drivers/video/fbsysfs.c
@@ -58,6 +58,7 @@ struct fb_info *framebuffer_alloc(size_t size, struct device *dev)
info->par = p + fb_info_size;
info->device = dev;
+ kref_init(&info->refcount);
#ifdef CONFIG_FB_BACKLIGHT
mutex_init(&info->bl_curve_mutex);
@@ -78,12 +79,17 @@ EXPORT_SYMBOL(framebuffer_alloc);
* framebuffer info structure.
*
*/
-void framebuffer_release(struct fb_info *info)
+void _fb_destroy(struct kref *ref)
{
+ struct fb_info *info = container_of(ref, struct fb_info, refcount);
+
+ if (info->fbops->fb_destroy)
+ info->fbops->fb_destroy(info);
+
kfree(info->apertures);
kfree(info);
}
-EXPORT_SYMBOL(framebuffer_release);
+EXPORT_SYMBOL(_fb_destroy);
static int activate(struct fb_info *fb_info, struct fb_var_screeninfo *var)
{
diff --git a/include/linux/fb.h b/include/linux/fb.h
index f0268de..9d59684 100644
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -834,6 +834,7 @@ struct fb_info {
int flags;
struct mutex lock; /* Lock for open/release/ioctl funcs */
struct mutex mm_lock; /* Lock for fb_mmap and smem_* fields */
+ struct kref refcount; /* Reference count of framebuffer */
struct fb_var_screeninfo var; /* Current var */
struct fb_fix_screeninfo fix; /* Current fix */
struct fb_monspecs monspecs; /* Current Monitor specs */
@@ -986,6 +987,8 @@ extern ssize_t fb_sys_write(struct fb_info *info, const char __user *buf,
size_t count, loff_t *ppos);
/* drivers/video/fbmem.c */
+extern struct fb_info *fb_get_registered(int fbidx);
+extern int fb_is_registered(struct fb_info *fb_info, int fbidx);
extern int register_framebuffer(struct fb_info *fb_info);
extern int unregister_framebuffer(struct fb_info *fb_info);
extern void remove_conflicting_framebuffers(struct apertures_struct *a,
@@ -1002,8 +1005,8 @@ extern int fb_get_color_depth(struct fb_var_screeninfo *var,
extern int fb_get_options(char *name, char **option);
extern int fb_new_modelist(struct fb_info *info);
-extern struct fb_info *registered_fb[FB_MAX];
-extern int num_registered_fb;
+/* extern struct fb_info *registered_fb[FB_MAX];
+extern int num_registered_fb; */
extern struct class *fb_class;
extern int lock_fb_info(struct fb_info *info);
@@ -1057,11 +1060,22 @@ static inline bool fb_be_math(struct fb_info *info)
/* drivers/video/fbsysfs.c */
extern struct fb_info *framebuffer_alloc(size_t size, struct device *dev);
-extern void framebuffer_release(struct fb_info *info);
+#define framebuffer_release(a) fb_put(a)
+extern void _fb_destroy(struct kref *ref);
extern int fb_init_device(struct fb_info *fb_info);
extern void fb_cleanup_device(struct fb_info *head);
extern void fb_bl_default_curve(struct fb_info *fb_info, u8 off, u8 min, u8 max);
+static inline void fb_get(struct fb_info *fb_info)
+{
+ kref_get(&fb_info->refcount);
+}
+static inline void fb_put(struct fb_info *fb_info)
+{
+ if (fb_info)
+ kref_put(&fb_info->refcount, _fb_destroy);
+}
+
/* drivers/video/fbmon.c */
#define FB_MAXTIMINGS 0
#define FB_VSYNCTIMINGS 1
--
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