diff options
Diffstat (limited to 'fs/partitions/devfs.c')
-rw-r--r-- | fs/partitions/devfs.c | 130 |
1 files changed, 0 insertions, 130 deletions
diff --git a/fs/partitions/devfs.c b/fs/partitions/devfs.c deleted file mode 100644 index 3f0a780..0000000 --- a/fs/partitions/devfs.c +++ /dev/null @@ -1,130 +0,0 @@ -/* - * This tries to keep block devices away from devfs as much as possible. - */ -#include <linux/fs.h> -#include <linux/devfs_fs_kernel.h> -#include <linux/vmalloc.h> -#include <linux/genhd.h> -#include <linux/bitops.h> -#include <linux/mutex.h> - - -struct unique_numspace { - u32 num_free; /* Num free in bits */ - u32 length; /* Array length in bytes */ - unsigned long *bits; - struct semaphore mutex; -}; - -static DEFINE_MUTEX(numspace_mutex); - -static int expand_numspace(struct unique_numspace *s) -{ - u32 length; - void *bits; - - if (s->length < 16) - length = 16; - else - length = s->length << 1; - - bits = vmalloc(length); - if (!bits) - return -ENOMEM; - if (s->bits) { - memcpy(bits, s->bits, s->length); - vfree(s->bits); - } - - s->num_free = (length - s->length) << 3; - s->bits = bits; - memset(bits + s->length, 0, length - s->length); - s->length = length; - - return 0; -} - -static int alloc_unique_number(struct unique_numspace *s) -{ - int rval = 0; - - mutex_lock(&numspace_mutex); - if (s->num_free < 1) - rval = expand_numspace(s); - if (!rval) { - rval = find_first_zero_bit(s->bits, s->length << 3); - --s->num_free; - __set_bit(rval, s->bits); - } - mutex_unlock(&numspace_mutex); - - return rval; -} - -static void dealloc_unique_number(struct unique_numspace *s, int number) -{ - int old_val; - - if (number >= 0) { - mutex_lock(&numspace_mutex); - old_val = __test_and_clear_bit(number, s->bits); - if (old_val) - ++s->num_free; - mutex_unlock(&numspace_mutex); - } -} - -static struct unique_numspace disc_numspace; -static struct unique_numspace cdrom_numspace; - -void devfs_add_partitioned(struct gendisk *disk) -{ - char dirname[64], symlink[16]; - - devfs_mk_dir(disk->devfs_name); - devfs_mk_bdev(MKDEV(disk->major, disk->first_minor), - S_IFBLK|S_IRUSR|S_IWUSR, - "%s/disc", disk->devfs_name); - - disk->number = alloc_unique_number(&disc_numspace); - - sprintf(symlink, "discs/disc%d", disk->number); - sprintf(dirname, "../%s", disk->devfs_name); - devfs_mk_symlink(symlink, dirname); - -} - -void devfs_add_disk(struct gendisk *disk) -{ - devfs_mk_bdev(MKDEV(disk->major, disk->first_minor), - (disk->flags & GENHD_FL_CD) ? - S_IFBLK|S_IRUGO|S_IWUGO : - S_IFBLK|S_IRUSR|S_IWUSR, - "%s", disk->devfs_name); - - if (disk->flags & GENHD_FL_CD) { - char dirname[64], symlink[16]; - - disk->number = alloc_unique_number(&cdrom_numspace); - - sprintf(symlink, "cdroms/cdrom%d", disk->number); - sprintf(dirname, "../%s", disk->devfs_name); - devfs_mk_symlink(symlink, dirname); - } -} - -void devfs_remove_disk(struct gendisk *disk) -{ - if (disk->minors != 1) { - devfs_remove("discs/disc%d", disk->number); - dealloc_unique_number(&disc_numspace, disk->number); - devfs_remove("%s/disc", disk->devfs_name); - } - if (disk->flags & GENHD_FL_CD) { - devfs_remove("cdroms/cdrom%d", disk->number); - dealloc_unique_number(&cdrom_numspace, disk->number); - } - devfs_remove(disk->devfs_name); -} - - |