diff options
Diffstat (limited to 'fs')
-rw-r--r-- | fs/char_dev.c | 58 | ||||
-rw-r--r-- | fs/proc/devices.c | 8 |
2 files changed, 45 insertions, 21 deletions
diff --git a/fs/char_dev.c b/fs/char_dev.c index fb8507f..ebcc8fb 100644 --- a/fs/char_dev.c +++ b/fs/char_dev.c @@ -28,6 +28,8 @@ static struct kobj_map *cdev_map; static DEFINE_MUTEX(chrdevs_lock); +#define CHRDEV_MAJOR_HASH_SIZE 255 + static struct char_device_struct { struct char_device_struct *next; unsigned int major; @@ -49,16 +51,39 @@ void chrdev_show(struct seq_file *f, off_t offset) { struct char_device_struct *cd; - if (offset < CHRDEV_MAJOR_HASH_SIZE) { - mutex_lock(&chrdevs_lock); - for (cd = chrdevs[offset]; cd; cd = cd->next) + mutex_lock(&chrdevs_lock); + for (cd = chrdevs[major_to_index(offset)]; cd; cd = cd->next) { + if (cd->major == offset) seq_printf(f, "%3d %s\n", cd->major, cd->name); - mutex_unlock(&chrdevs_lock); } + mutex_unlock(&chrdevs_lock); } #endif /* CONFIG_PROC_FS */ +static int find_dynamic_major(void) +{ + int i; + struct char_device_struct *cd; + + for (i = ARRAY_SIZE(chrdevs)-1; i > CHRDEV_MAJOR_DYN_END; i--) { + if (chrdevs[i] == NULL) + return i; + } + + for (i = CHRDEV_MAJOR_DYN_EXT_START; + i > CHRDEV_MAJOR_DYN_EXT_END; i--) { + for (cd = chrdevs[major_to_index(i)]; cd; cd = cd->next) + if (cd->major == i) + break; + + if (cd == NULL || cd->major != i) + return i; + } + + return -EBUSY; +} + /* * Register a single major with a specified minor range. * @@ -84,22 +109,21 @@ __register_chrdev_region(unsigned int major, unsigned int baseminor, mutex_lock(&chrdevs_lock); - /* temporary */ if (major == 0) { - for (i = ARRAY_SIZE(chrdevs)-1; i > 0; i--) { - if (chrdevs[i] == NULL) - break; - } - - if (i < CHRDEV_MAJOR_DYN_END) - pr_warn("CHRDEV \"%s\" major number %d goes below the dynamic allocation range\n", - name, i); - - if (i == 0) { - ret = -EBUSY; + ret = find_dynamic_major(); + if (ret < 0) { + pr_err("CHRDEV \"%s\" dynamic allocation region is full\n", + name); goto out; } - major = i; + major = ret; + } + + if (major >= CHRDEV_MAJOR_MAX) { + pr_err("CHRDEV \"%s\" major requested (%d) is greater than the maximum (%d)\n", + name, major, CHRDEV_MAJOR_MAX); + ret = -EINVAL; + goto out; } cd->major = major; diff --git a/fs/proc/devices.c b/fs/proc/devices.c index 50493ed..e570934 100644 --- a/fs/proc/devices.c +++ b/fs/proc/devices.c @@ -7,14 +7,14 @@ static int devinfo_show(struct seq_file *f, void *v) { int i = *(loff_t *) v; - if (i < CHRDEV_MAJOR_HASH_SIZE) { + if (i < CHRDEV_MAJOR_MAX) { if (i == 0) seq_puts(f, "Character devices:\n"); chrdev_show(f, i); } #ifdef CONFIG_BLOCK else { - i -= CHRDEV_MAJOR_HASH_SIZE; + i -= CHRDEV_MAJOR_MAX; if (i == 0) seq_puts(f, "\nBlock devices:\n"); blkdev_show(f, i); @@ -25,7 +25,7 @@ static int devinfo_show(struct seq_file *f, void *v) static void *devinfo_start(struct seq_file *f, loff_t *pos) { - if (*pos < (BLKDEV_MAJOR_HASH_SIZE + CHRDEV_MAJOR_HASH_SIZE)) + if (*pos < (BLKDEV_MAJOR_MAX + CHRDEV_MAJOR_MAX)) return pos; return NULL; } @@ -33,7 +33,7 @@ static void *devinfo_start(struct seq_file *f, loff_t *pos) static void *devinfo_next(struct seq_file *f, void *v, loff_t *pos) { (*pos)++; - if (*pos >= (BLKDEV_MAJOR_HASH_SIZE + CHRDEV_MAJOR_HASH_SIZE)) + if (*pos >= (BLKDEV_MAJOR_MAX + CHRDEV_MAJOR_MAX)) return NULL; return pos; } |