From: Krzysztof Helt Date: Tue, 30 Jun 2009 18:41:29 +0000 (-0700) Subject: fbdev: add mutex for fb_mmap locking X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=537a1bf0;p=linux-beck.git fbdev: add mutex for fb_mmap locking Add a mutex to avoid a circular locking problem between the mm layer semaphore and fbdev ioctl mutex through the fb_mmap() call. Also, add mutex to all places where smem_start and smem_len fields change so the mutex inside the fb_mmap() is actually used. Changing of these fields before calling the framebuffer_register() are not mutexed. This is 2.6.31 material. It removes one lockdep (fb_mmap() and register_framebuffer()) but there is still another one (fb_release() and register_framebuffer()). It also cleans up handling of the smem_start and smem_len fields used by mutexed section of the fb_mmap(). Signed-off-by: Krzysztof Helt Cc: Peter Zijlstra Cc: "Rafael J. Wysocki" Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/drivers/video/atafb.c b/drivers/video/atafb.c index 018850c116c6..497ff8af03ed 100644 --- a/drivers/video/atafb.c +++ b/drivers/video/atafb.c @@ -2414,7 +2414,10 @@ static int atafb_get_fix(struct fb_fix_screeninfo *fix, struct fb_info *info) if (err) return err; memset(fix, 0, sizeof(struct fb_fix_screeninfo)); - return fbhw->encode_fix(fix, &par); + mutex_lock(&info->mm_lock); + err = fbhw->encode_fix(fix, &par); + mutex_unlock(&info->mm_lock); + return err; } static int atafb_get_var(struct fb_var_screeninfo *var, struct fb_info *info) @@ -2743,7 +2746,9 @@ static int atafb_set_par(struct fb_info *info) /* Decode wanted screen parameters */ fbhw->decode_var(&info->var, par); + mutex_lock(&info->mm_lock); fbhw->encode_fix(&info->fix, par); + mutex_unlock(&info->mm_lock); /* Set new videomode */ ata_set_par(par); diff --git a/drivers/video/atmel_lcdfb.c b/drivers/video/atmel_lcdfb.c index 5afd64482f55..cb88394ba995 100644 --- a/drivers/video/atmel_lcdfb.c +++ b/drivers/video/atmel_lcdfb.c @@ -270,7 +270,9 @@ static int atmel_lcdfb_alloc_video_memory(struct atmel_lcdfb_info *sinfo) smem_len = (var->xres_virtual * var->yres_virtual * ((var->bits_per_pixel + 7) / 8)); + mutex_lock(&info->mm_lock); info->fix.smem_len = max(smem_len, sinfo->smem_len); + mutex_unlock(&info->mm_lock); info->screen_base = dma_alloc_writecombine(info->device, info->fix.smem_len, (dma_addr_t *)&info->fix.smem_start, GFP_KERNEL); diff --git a/drivers/video/fbmem.c b/drivers/video/fbmem.c index f8a09bf8d0cd..53ea05645ff8 100644 --- a/drivers/video/fbmem.c +++ b/drivers/video/fbmem.c @@ -1310,8 +1310,6 @@ static long fb_compat_ioctl(struct file *file, unsigned int cmd, static int fb_mmap(struct file *file, struct vm_area_struct * vma) -__acquires(&info->lock) -__releases(&info->lock) { int fbidx = iminor(file->f_path.dentry->d_inode); struct fb_info *info = registered_fb[fbidx]; @@ -1325,16 +1323,14 @@ __releases(&info->lock) off = vma->vm_pgoff << PAGE_SHIFT; if (!fb) return -ENODEV; + mutex_lock(&info->mm_lock); if (fb->fb_mmap) { int res; - mutex_lock(&info->lock); res = fb->fb_mmap(info, vma); - mutex_unlock(&info->lock); + mutex_unlock(&info->mm_lock); return res; } - mutex_lock(&info->lock); - /* frame buffer memory */ start = info->fix.smem_start; len = PAGE_ALIGN((start & ~PAGE_MASK) + info->fix.smem_len); @@ -1342,13 +1338,13 @@ __releases(&info->lock) /* memory mapped io */ off -= len; if (info->var.accel_flags) { - mutex_unlock(&info->lock); + mutex_unlock(&info->mm_lock); return -EINVAL; } start = info->fix.mmio_start; len = PAGE_ALIGN((start & ~PAGE_MASK) + info->fix.mmio_len); } - mutex_unlock(&info->lock); + mutex_unlock(&info->mm_lock); start &= PAGE_MASK; if ((vma->vm_end - vma->vm_start + off) > len) return -EINVAL; @@ -1518,6 +1514,7 @@ register_framebuffer(struct fb_info *fb_info) break; fb_info->node = i; mutex_init(&fb_info->lock); + mutex_init(&fb_info->mm_lock); fb_info->dev = device_create(fb_class, fb_info->device, MKDEV(FB_MAJOR, i), NULL, "fb%d", i); diff --git a/drivers/video/fsl-diu-fb.c b/drivers/video/fsl-diu-fb.c index f153c581cbd7..0bf2190928d0 100644 --- a/drivers/video/fsl-diu-fb.c +++ b/drivers/video/fsl-diu-fb.c @@ -750,24 +750,26 @@ static void update_lcdc(struct fb_info *info) static int map_video_memory(struct fb_info *info) { phys_addr_t phys; + u32 smem_len = info->fix.line_length * info->var.yres_virtual; pr_debug("info->var.xres_virtual = %d\n", info->var.xres_virtual); pr_debug("info->var.yres_virtual = %d\n", info->var.yres_virtual); pr_debug("info->fix.line_length = %d\n", info->fix.line_length); + pr_debug("MAP_VIDEO_MEMORY: smem_len = %u\n", smem_len); - info->fix.smem_len = info->fix.line_length * info->var.yres_virtual; - pr_debug("MAP_VIDEO_MEMORY: smem_len = %d\n", info->fix.smem_len); - info->screen_base = fsl_diu_alloc(info->fix.smem_len, &phys); + info->screen_base = fsl_diu_alloc(smem_len, &phys); if (info->screen_base == NULL) { printk(KERN_ERR "Unable to allocate fb memory\n"); return -ENOMEM; } + mutex_lock(&info->mm_lock); info->fix.smem_start = (unsigned long) phys; + info->fix.smem_len = smem_len; + mutex_unlock(&info->mm_lock); info->screen_size = info->fix.smem_len; pr_debug("Allocated fb @ paddr=0x%08lx, size=%d.\n", - info->fix.smem_start, - info->fix.smem_len); + info->fix.smem_start, info->fix.smem_len); pr_debug("screen base %p\n", info->screen_base); return 0; @@ -776,9 +778,11 @@ static int map_video_memory(struct fb_info *info) static void unmap_video_memory(struct fb_info *info) { fsl_diu_free(info->screen_base, info->fix.smem_len); + mutex_lock(&info->mm_lock); info->screen_base = NULL; info->fix.smem_start = 0; info->fix.smem_len = 0; + mutex_unlock(&info->mm_lock); } /* diff --git a/drivers/video/i810/i810_main.c b/drivers/video/i810/i810_main.c index 2e940199fc89..71960672d721 100644 --- a/drivers/video/i810/i810_main.c +++ b/drivers/video/i810/i810_main.c @@ -1090,8 +1090,10 @@ static int encode_fix(struct fb_fix_screeninfo *fix, struct fb_info *info) memset(fix, 0, sizeof(struct fb_fix_screeninfo)); strcpy(fix->id, "I810"); + mutex_lock(&info->mm_lock); fix->smem_start = par->fb.physical; fix->smem_len = par->fb.size; + mutex_unlock(&info->mm_lock); fix->type = FB_TYPE_PACKED_PIXELS; fix->type_aux = 0; fix->xpanstep = 8; diff --git a/drivers/video/matrox/matroxfb_base.c b/drivers/video/matrox/matroxfb_base.c index 8e7a275df50c..59c3a2e14913 100644 --- a/drivers/video/matrox/matroxfb_base.c +++ b/drivers/video/matrox/matroxfb_base.c @@ -724,8 +724,10 @@ static void matroxfb_update_fix(WPMINFO2) struct fb_fix_screeninfo *fix = &ACCESS_FBINFO(fbcon).fix; DBG(__func__) + mutex_lock(&ACCESS_FBINFO(fbcon).mm_lock); fix->smem_start = ACCESS_FBINFO(video.base) + ACCESS_FBINFO(curr.ydstorg.bytes); fix->smem_len = ACCESS_FBINFO(video.len_usable) - ACCESS_FBINFO(curr.ydstorg.bytes); + mutex_unlock(&ACCESS_FBINFO(fbcon).mm_lock); } static int matroxfb_check_var(struct fb_var_screeninfo *var, struct fb_info *info) @@ -2081,6 +2083,7 @@ static int matroxfb_probe(struct pci_dev* pdev, const struct pci_device_id* dumm spin_lock_init(&ACCESS_FBINFO(lock.accel)); init_rwsem(&ACCESS_FBINFO(crtc2.lock)); init_rwsem(&ACCESS_FBINFO(altout.lock)); + mutex_init(&ACCESS_FBINFO(fbcon).mm_lock); ACCESS_FBINFO(irq_flags) = 0; init_waitqueue_head(&ACCESS_FBINFO(crtc1.vsync.wait)); init_waitqueue_head(&ACCESS_FBINFO(crtc2.vsync.wait)); diff --git a/drivers/video/matrox/matroxfb_crtc2.c b/drivers/video/matrox/matroxfb_crtc2.c index 7ac4c5f6145d..909e10a11898 100644 --- a/drivers/video/matrox/matroxfb_crtc2.c +++ b/drivers/video/matrox/matroxfb_crtc2.c @@ -289,13 +289,16 @@ static int matroxfb_dh_release(struct fb_info* info, int user) { #undef m2info } -static void matroxfb_dh_init_fix(struct matroxfb_dh_fb_info *m2info) { +static void matroxfb_dh_init_fix(struct matroxfb_dh_fb_info *m2info) +{ struct fb_fix_screeninfo *fix = &m2info->fbcon.fix; strcpy(fix->id, "MATROX DH"); + mutex_lock(&m2info->fbcon.mm_lock); fix->smem_start = m2info->video.base; fix->smem_len = m2info->video.len_usable; + mutex_unlock(&m2info->fbcon.mm_lock); fix->ypanstep = 1; fix->ywrapstep = 0; fix->xpanstep = 8; /* TBD */ diff --git a/drivers/video/mx3fb.c b/drivers/video/mx3fb.c index b7af5256e887..567fb944bd2a 100644 --- a/drivers/video/mx3fb.c +++ b/drivers/video/mx3fb.c @@ -669,7 +669,7 @@ static uint32_t bpp_to_pixfmt(int bpp) } static int mx3fb_blank(int blank, struct fb_info *fbi); -static int mx3fb_map_video_memory(struct fb_info *fbi); +static int mx3fb_map_video_memory(struct fb_info *fbi, unsigned int mem_len); static int mx3fb_unmap_video_memory(struct fb_info *fbi); /** @@ -742,8 +742,7 @@ static int mx3fb_set_par(struct fb_info *fbi) if (fbi->fix.smem_start) mx3fb_unmap_video_memory(fbi); - fbi->fix.smem_len = mem_len; - if (mx3fb_map_video_memory(fbi) < 0) { + if (mx3fb_map_video_memory(fbi, mem_len) < 0) { mutex_unlock(&mx3_fbi->mutex); return -ENOMEM; } @@ -1198,6 +1197,7 @@ static int mx3fb_resume(struct platform_device *pdev) /** * mx3fb_map_video_memory() - allocates the DRAM memory for the frame buffer. * @fbi: framebuffer information pointer + * @mem_len: length of mapped memory * @return: Error code indicating success or failure * * This buffer is remapped into a non-cached, non-buffered, memory region to @@ -1205,23 +1205,26 @@ static int mx3fb_resume(struct platform_device *pdev) * area is remapped, all virtual memory access to the video memory should occur * at the new region. */ -static int mx3fb_map_video_memory(struct fb_info *fbi) +static int mx3fb_map_video_memory(struct fb_info *fbi, unsigned int mem_len) { int retval = 0; dma_addr_t addr; fbi->screen_base = dma_alloc_writecombine(fbi->device, - fbi->fix.smem_len, + mem_len, &addr, GFP_DMA); if (!fbi->screen_base) { dev_err(fbi->device, "Cannot allocate %u bytes framebuffer memory\n", - fbi->fix.smem_len); + mem_len); retval = -EBUSY; goto err0; } + mutex_lock(&fbi->mm_lock); fbi->fix.smem_start = addr; + fbi->fix.smem_len = mem_len; + mutex_unlock(&fbi->mm_lock); dev_dbg(fbi->device, "allocated fb @ p=0x%08x, v=0x%p, size=%d.\n", (uint32_t) fbi->fix.smem_start, fbi->screen_base, fbi->fix.smem_len); @@ -1251,8 +1254,10 @@ static int mx3fb_unmap_video_memory(struct fb_info *fbi) fbi->screen_base, fbi->fix.smem_start); fbi->screen_base = 0; + mutex_lock(&fbi->mm_lock); fbi->fix.smem_start = 0; fbi->fix.smem_len = 0; + mutex_unlock(&fbi->mm_lock); return 0; } diff --git a/drivers/video/omap/omapfb_main.c b/drivers/video/omap/omapfb_main.c index 060d72fe57cb..4ea99bfc37b4 100644 --- a/drivers/video/omap/omapfb_main.c +++ b/drivers/video/omap/omapfb_main.c @@ -393,8 +393,10 @@ static void set_fb_fix(struct fb_info *fbi) rg = &plane->fbdev->mem_desc.region[plane->idx]; fbi->screen_base = rg->vaddr; + mutex_lock(&fbi->mm_lock); fix->smem_start = rg->paddr; fix->smem_len = rg->size; + mutex_unlock(&fbi->mm_lock); fix->type = FB_TYPE_PACKED_PIXELS; bpp = var->bits_per_pixel; @@ -886,8 +888,10 @@ static int omapfb_setup_mem(struct fb_info *fbi, struct omapfb_mem_info *mi) * plane memory is dealloce'd, the other * screen parameters in var / fix are invalid. */ + mutex_lock(&fbi->mm_lock); fbi->fix.smem_start = 0; fbi->fix.smem_len = 0; + mutex_unlock(&fbi->mm_lock); } } } diff --git a/drivers/video/platinumfb.c b/drivers/video/platinumfb.c index 03b3670130a0..bacfabd9ce16 100644 --- a/drivers/video/platinumfb.c +++ b/drivers/video/platinumfb.c @@ -141,7 +141,9 @@ static int platinumfb_set_par (struct fb_info *info) offset = 0x10; info->screen_base = pinfo->frame_buffer + init->fb_offset + offset; + mutex_lock(&info->mm_lock); info->fix.smem_start = (pinfo->frame_buffer_phys) + init->fb_offset + offset; + mutex_unlock(&info->mm_lock); info->fix.visual = (pinfo->cmode == CMODE_8) ? FB_VISUAL_PSEUDOCOLOR : FB_VISUAL_DIRECTCOLOR; info->fix.line_length = vmode_attrs[pinfo->vmode-1].hres * (1<cmode) diff --git a/drivers/video/pxafb.c b/drivers/video/pxafb.c index 0889d50c3288..6506117c134b 100644 --- a/drivers/video/pxafb.c +++ b/drivers/video/pxafb.c @@ -815,8 +815,10 @@ static int overlayfb_map_video_memory(struct pxafb_layer *ofb) ofb->video_mem_phys = virt_to_phys(ofb->video_mem); ofb->video_mem_size = size; + mutex_lock(&ofb->fb.mm_lock); ofb->fb.fix.smem_start = ofb->video_mem_phys; ofb->fb.fix.smem_len = ofb->fb.fix.line_length * var->yres_virtual; + mutex_unlock(&ofb->fb.mm_lock); ofb->fb.screen_base = ofb->video_mem; return 0; } diff --git a/drivers/video/sh7760fb.c b/drivers/video/sh7760fb.c index 653bdfee3057..9f6d6e61f0cc 100644 --- a/drivers/video/sh7760fb.c +++ b/drivers/video/sh7760fb.c @@ -120,18 +120,6 @@ static int sh7760_setcolreg (u_int regno, return 0; } -static void encode_fix(struct fb_fix_screeninfo *fix, struct fb_info *info, - unsigned long stride) -{ - memset(fix, 0, sizeof(struct fb_fix_screeninfo)); - strcpy(fix->id, "sh7760-lcdc"); - - fix->smem_start = (unsigned long)info->screen_base; - fix->smem_len = info->screen_size; - - fix->line_length = stride; -} - static int sh7760fb_get_color_info(struct device *dev, u16 lddfr, int *bpp, int *gray) { @@ -334,7 +322,8 @@ static int sh7760fb_set_par(struct fb_info *info) iowrite32(ldsarl, par->base + LDSARL); /* mem for lower half of DSTN */ - encode_fix(&info->fix, info, stride); + info->fix.line_length = stride; + sh7760fb_check_var(&info->var, info); sh7760fb_blank(FB_BLANK_UNBLANK, info); /* panel on! */ @@ -435,6 +424,8 @@ static int sh7760fb_alloc_mem(struct fb_info *info) info->screen_base = fbmem; info->screen_size = vram; + info->fix.smem_start = (unsigned long)info->screen_base; + info->fix.smem_len = info->screen_size; return 0; } @@ -520,6 +511,8 @@ static int __devinit sh7760fb_probe(struct platform_device *pdev) info->var.transp.length = 0; info->var.transp.msb_right = 0; + strcpy(info->fix.id, "sh7760-lcdc"); + /* set the DON2 bit now, before cmap allocation, as it will randomize * palette memory. */ diff --git a/drivers/video/sis/sis_main.c b/drivers/video/sis/sis_main.c index 7072d19080d5..fd33455389b8 100644 --- a/drivers/video/sis/sis_main.c +++ b/drivers/video/sis/sis_main.c @@ -1847,8 +1847,10 @@ sisfb_get_fix(struct fb_fix_screeninfo *fix, int con, struct fb_info *info) strcpy(fix->id, ivideo->myid); + mutex_lock(&info->mm_lock); fix->smem_start = ivideo->video_base + ivideo->video_offset; fix->smem_len = ivideo->sisfb_mem; + mutex_unlock(&info->mm_lock); fix->type = FB_TYPE_PACKED_PIXELS; fix->type_aux = 0; fix->visual = (ivideo->video_bpp == 8) ? FB_VISUAL_PSEUDOCOLOR : FB_VISUAL_TRUECOLOR; diff --git a/drivers/video/sm501fb.c b/drivers/video/sm501fb.c index eb5d73a06702..98f24f0ec00d 100644 --- a/drivers/video/sm501fb.c +++ b/drivers/video/sm501fb.c @@ -145,7 +145,7 @@ static inline void sm501fb_sync_regs(struct sm501fb_info *info) #define SM501_MEMF_ACCEL (8) static int sm501_alloc_mem(struct sm501fb_info *inf, struct sm501_mem *mem, - unsigned int why, size_t size) + unsigned int why, size_t size, u32 smem_len) { struct sm501fb_par *par; struct fb_info *fbi; @@ -172,7 +172,7 @@ static int sm501_alloc_mem(struct sm501fb_info *inf, struct sm501_mem *mem, if (ptr > 0) ptr &= ~(PAGE_SIZE - 1); - if (fbi && ptr < fbi->fix.smem_len) + if (fbi && ptr < smem_len) return -ENOMEM; break; @@ -197,7 +197,7 @@ static int sm501_alloc_mem(struct sm501fb_info *inf, struct sm501_mem *mem, case SM501_MEMF_ACCEL: fbi = inf->fb[HEAD_CRT]; - ptr = fbi ? fbi->fix.smem_len : 0; + ptr = fbi ? smem_len : 0; fbi = inf->fb[HEAD_PANEL]; if (fbi) { @@ -413,6 +413,7 @@ static int sm501fb_set_par_common(struct fb_info *info, unsigned int mem_type; unsigned int clock_type; unsigned int head_addr; + unsigned int smem_len; dev_dbg(fbi->dev, "%s: %dx%d, bpp = %d, virtual %dx%d\n", __func__, var->xres, var->yres, var->bits_per_pixel, @@ -453,18 +454,20 @@ static int sm501fb_set_par_common(struct fb_info *info, /* allocate fb memory within 501 */ info->fix.line_length = (var->xres_virtual * var->bits_per_pixel)/8; - info->fix.smem_len = info->fix.line_length * var->yres_virtual; + smem_len = info->fix.line_length * var->yres_virtual; dev_dbg(fbi->dev, "%s: line length = %u\n", __func__, info->fix.line_length); - if (sm501_alloc_mem(fbi, &par->screen, mem_type, - info->fix.smem_len)) { + if (sm501_alloc_mem(fbi, &par->screen, mem_type, smem_len, smem_len)) { dev_err(fbi->dev, "no memory available\n"); return -ENOMEM; } + mutex_lock(&info->mm_lock); info->fix.smem_start = fbi->fbmem_res->start + par->screen.sm_addr; + info->fix.smem_len = smem_len; + mutex_unlock(&info->mm_lock); info->screen_base = fbi->fbmem + par->screen.sm_addr; info->screen_size = info->fix.smem_len; @@ -637,7 +640,8 @@ static int sm501fb_set_par_crt(struct fb_info *info) if ((control & SM501_DC_CRT_CONTROL_SEL) == 0) { /* the head is displaying panel data... */ - sm501_alloc_mem(fbi, &par->screen, SM501_MEMF_CRT, 0); + sm501_alloc_mem(fbi, &par->screen, SM501_MEMF_CRT, 0, + info->fix.smem_len); goto out_update; } @@ -1289,7 +1293,8 @@ static int sm501_init_cursor(struct fb_info *fbi, unsigned int reg_base) par->cursor_regs = info->regs + reg_base; - ret = sm501_alloc_mem(info, &par->cursor, SM501_MEMF_CURSOR, 1024); + ret = sm501_alloc_mem(info, &par->cursor, SM501_MEMF_CURSOR, 1024, + fbi->fix.smem_len); if (ret < 0) return ret; diff --git a/drivers/video/w100fb.c b/drivers/video/w100fb.c index d0674f1e3f10..8a141c2c637b 100644 --- a/drivers/video/w100fb.c +++ b/drivers/video/w100fb.c @@ -523,6 +523,7 @@ static int w100fb_set_par(struct fb_info *info) info->fix.ywrapstep = 0; info->fix.line_length = par->xres * BITS_PER_PIXEL / 8; + mutex_lock(&info->mm_lock); if ((par->xres*par->yres*BITS_PER_PIXEL/8) > (MEM_INT_SIZE+1)) { par->extmem_active = 1; info->fix.smem_len = par->mach->mem->size+1; @@ -530,6 +531,7 @@ static int w100fb_set_par(struct fb_info *info) par->extmem_active = 0; info->fix.smem_len = MEM_INT_SIZE+1; } + mutex_unlock(&info->mm_lock); w100fb_activate_var(par); } diff --git a/include/linux/fb.h b/include/linux/fb.h index dd68358996b7..f847df9e99b6 100644 --- a/include/linux/fb.h +++ b/include/linux/fb.h @@ -819,6 +819,7 @@ struct fb_info { int node; int flags; struct mutex lock; /* Lock for open/release/ioctl funcs */ + struct mutex mm_lock; /* Lock for fb_mmap and smem_* fields */ struct fb_var_screeninfo var; /* Current var */ struct fb_fix_screeninfo fix; /* Current fix */ struct fb_monspecs monspecs; /* Current Monitor specs */