Commit 298d8a04 authored by Christoph Hellwig's avatar Christoph Hellwig

[PATCH] umode_t changes from Adam's mini-devfs

The use of umode_t instead of devfs-specific char vs block #defines
in Adam's mini-devfs patch makes sense independant of whether his patch
should get merged.  While reviewing his changes I also notices that
most of the number allocation functionality in devfs has no business
beeing exported.  In addition I cleaned up devfs_alloc_devnum/
devfs_dealloc_devnum a bit.
parent b30d9e8b
...@@ -685,6 +685,8 @@ ...@@ -685,6 +685,8 @@
#include <asm/bitops.h> #include <asm/bitops.h>
#include <asm/atomic.h> #include <asm/atomic.h>
#include "internal.h"
#define DEVFS_VERSION "1.22 (20021013)" #define DEVFS_VERSION "1.22 (20021013)"
#define DEVFS_NAME "devfs" #define DEVFS_NAME "devfs"
...@@ -935,9 +937,9 @@ void devfs_put (devfs_handle_t de) ...@@ -935,9 +937,9 @@ void devfs_put (devfs_handle_t de)
de->parent ? de->parent->name : "no parent"); de->parent ? de->parent->name : "no parent");
if ( S_ISLNK (de->mode) ) kfree (de->u.symlink.linkname); if ( S_ISLNK (de->mode) ) kfree (de->u.symlink.linkname);
if ( S_ISCHR (de->mode) && de->u.cdev.autogen ) if ( S_ISCHR (de->mode) && de->u.cdev.autogen )
devfs_dealloc_devnum (DEVFS_SPECIAL_CHR, de->u.cdev.dev); devfs_dealloc_devnum (de->mode, de->u.cdev.dev);
if ( S_ISBLK (de->mode) && de->u.bdev.autogen ) if ( S_ISBLK (de->mode) && de->u.bdev.autogen )
devfs_dealloc_devnum(DEVFS_SPECIAL_BLK, de->u.bdev.dev); devfs_dealloc_devnum (de->mode, de->u.bdev.dev);
WRITE_ENTRY_MAGIC (de, 0); WRITE_ENTRY_MAGIC (de, 0);
#ifdef CONFIG_DEVFS_DEBUG #ifdef CONFIG_DEVFS_DEBUG
spin_lock (&stat_lock); spin_lock (&stat_lock);
...@@ -1102,13 +1104,13 @@ static struct devfs_entry *_devfs_get_root_entry (void) ...@@ -1102,13 +1104,13 @@ static struct devfs_entry *_devfs_get_root_entry (void)
/* And create the entry for ".devfsd" */ /* And create the entry for ".devfsd" */
if ( ( new = _devfs_alloc_entry (".devfsd", 0, S_IFCHR |S_IRUSR |S_IWUSR) ) if ( ( new = _devfs_alloc_entry (".devfsd", 0, S_IFCHR |S_IRUSR |S_IWUSR) )
== NULL ) return NULL; == NULL ) return NULL;
new->u.cdev.dev = devfs_alloc_devnum (DEVFS_SPECIAL_CHR); new->u.cdev.dev = devfs_alloc_devnum (S_IFCHR |S_IRUSR |S_IWUSR);
new->u.cdev.ops = &devfsd_fops; new->u.cdev.ops = &devfsd_fops;
_devfs_append_entry (root_entry, new, FALSE, NULL); _devfs_append_entry (root_entry, new, FALSE, NULL);
#ifdef CONFIG_DEVFS_DEBUG #ifdef CONFIG_DEVFS_DEBUG
if ( ( new = _devfs_alloc_entry (".stat", 0, S_IFCHR | S_IRUGO | S_IWUGO) ) if ( ( new = _devfs_alloc_entry (".stat", 0, S_IFCHR | S_IRUGO | S_IWUGO) )
== NULL ) return NULL; == NULL ) return NULL;
new->u.cdev.dev = devfs_alloc_devnum (DEVFS_SPECIAL_CHR); new->u.cdev.dev = devfs_alloc_devnum (S_IFCHR | S_IRUGO | S_IWUGO);
new->u.cdev.ops = &stat_fops; new->u.cdev.ops = &stat_fops;
_devfs_append_entry (root_entry, new, FALSE, NULL); _devfs_append_entry (root_entry, new, FALSE, NULL);
#endif #endif
...@@ -1469,7 +1471,6 @@ devfs_handle_t devfs_register (devfs_handle_t dir, const char *name, ...@@ -1469,7 +1471,6 @@ devfs_handle_t devfs_register (devfs_handle_t dir, const char *name,
unsigned int major, unsigned int minor, unsigned int major, unsigned int minor,
umode_t mode, void *ops, void *info) umode_t mode, void *ops, void *info)
{ {
char devtype = S_ISCHR (mode) ? DEVFS_SPECIAL_CHR : DEVFS_SPECIAL_BLK;
int err; int err;
dev_t devnum = 0, dev = MKDEV(major, minor); dev_t devnum = 0, dev = MKDEV(major, minor);
struct devfs_entry *de; struct devfs_entry *de;
...@@ -1497,7 +1498,7 @@ devfs_handle_t devfs_register (devfs_handle_t dir, const char *name, ...@@ -1497,7 +1498,7 @@ devfs_handle_t devfs_register (devfs_handle_t dir, const char *name,
if ( ( S_ISCHR (mode) || S_ISBLK (mode) ) && if ( ( S_ISCHR (mode) || S_ISBLK (mode) ) &&
(flags & DEVFS_FL_AUTO_DEVNUM) ) (flags & DEVFS_FL_AUTO_DEVNUM) )
{ {
devnum = devfs_alloc_devnum (devtype); devnum = devfs_alloc_devnum (mode);
if (!devnum) { if (!devnum) {
PRINTK ("(%s): exhausted %s device numbers\n", PRINTK ("(%s): exhausted %s device numbers\n",
name, S_ISCHR (mode) ? "char" : "block"); name, S_ISCHR (mode) ? "char" : "block");
...@@ -1508,7 +1509,7 @@ devfs_handle_t devfs_register (devfs_handle_t dir, const char *name, ...@@ -1508,7 +1509,7 @@ devfs_handle_t devfs_register (devfs_handle_t dir, const char *name,
if ( ( de = _devfs_prepare_leaf (&dir, name, mode) ) == NULL ) if ( ( de = _devfs_prepare_leaf (&dir, name, mode) ) == NULL )
{ {
PRINTK ("(%s): could not prepare leaf\n", name); PRINTK ("(%s): could not prepare leaf\n", name);
if (devnum) devfs_dealloc_devnum (devtype, devnum); if (devnum) devfs_dealloc_devnum (mode, devnum);
return NULL; return NULL;
} }
if (S_ISCHR (mode)) { if (S_ISCHR (mode)) {
...@@ -1544,7 +1545,7 @@ devfs_handle_t devfs_register (devfs_handle_t dir, const char *name, ...@@ -1544,7 +1545,7 @@ devfs_handle_t devfs_register (devfs_handle_t dir, const char *name,
{ {
PRINTK ("(%s): could not append to parent, err: %d\n", name, err); PRINTK ("(%s): could not append to parent, err: %d\n", name, err);
devfs_put (dir); devfs_put (dir);
if (devnum) devfs_dealloc_devnum (devtype, devnum); if (devnum) devfs_dealloc_devnum (mode, devnum);
return NULL; return NULL;
} }
DPRINTK (DEBUG_REGISTER, "(%s): de: %p dir: %p \"%s\" pp: %p\n", DPRINTK (DEBUG_REGISTER, "(%s): de: %p dir: %p \"%s\" pp: %p\n",
...@@ -1953,7 +1954,6 @@ EXPORT_SYMBOL(devfs_mk_symlink); ...@@ -1953,7 +1954,6 @@ EXPORT_SYMBOL(devfs_mk_symlink);
EXPORT_SYMBOL(devfs_mk_dir); EXPORT_SYMBOL(devfs_mk_dir);
EXPORT_SYMBOL(devfs_remove); EXPORT_SYMBOL(devfs_remove);
EXPORT_SYMBOL(devfs_generate_path); EXPORT_SYMBOL(devfs_generate_path);
EXPORT_SYMBOL(devfs_only);
/** /**
......
extern dev_t devfs_alloc_devnum(umode_t mode);
extern void devfs_dealloc_devnum(umode_t mode, dev_t devnum);
...@@ -60,14 +60,18 @@ ...@@ -60,14 +60,18 @@
Copied and used macro for error messages from fs/devfs/base.c Copied and used macro for error messages from fs/devfs/base.c
20021013 Richard Gooch <rgooch@atnf.csiro.au> 20021013 Richard Gooch <rgooch@atnf.csiro.au>
Documentation fix. Documentation fix.
20030101 Adam J. Richter <adam@yggdrasil.com>
Eliminate DEVFS_SPECIAL_{CHR,BLK}. Use mode_t instead.
20030106 Christoph Hellwig <hch@infradead.org>
Rewrite devfs_{,de}alloc_devnum to look like C code.
*/ */
#include <linux/module.h> #include <linux/module.h>
#include <linux/init.h> #include <linux/init.h>
#include <linux/devfs_fs_kernel.h> #include <linux/devfs_fs_kernel.h>
#include <linux/slab.h> #include <linux/slab.h>
#include <linux/vmalloc.h> #include <linux/vmalloc.h>
#include <asm/bitops.h> #include <asm/bitops.h>
#include "internal.h"
#define PRINTK(format, args...) \ #define PRINTK(format, args...) \
{printk (KERN_ERR "%s" format, __FUNCTION__ , ## args);} {printk (KERN_ERR "%s" format, __FUNCTION__ , ## args);}
...@@ -145,49 +149,11 @@ static struct major_list char_major_list = ...@@ -145,49 +149,11 @@ static struct major_list char_major_list =
/** /**
* devfs_alloc_major - Allocate a major number. * devfs_alloc_major - Allocate a major number.
* @type: The type of the major (DEVFS_SPECIAL_CHR or DEVFS_SPECIAL_BLK) * @mode: The file mode (must be block device or character device).
* Returns the allocated major, else -1 if none are available. * Returns the allocated major, else -1 if none are available.
* This routine is thread safe and does not block. * This routine is thread safe and does not block.
*/ */
int devfs_alloc_major (char type)
{
int major;
struct major_list *list;
list = (type == DEVFS_SPECIAL_CHR) ? &char_major_list : &block_major_list;
spin_lock (&list->lock);
major = find_first_zero_bit (list->bits, 256);
if (major < 256) __set_bit (major, list->bits);
else major = -1;
spin_unlock (&list->lock);
return major;
} /* End Function devfs_alloc_major */
EXPORT_SYMBOL(devfs_alloc_major);
/**
* devfs_dealloc_major - Deallocate a major number.
* @type: The type of the major (DEVFS_SPECIAL_CHR or DEVFS_SPECIAL_BLK)
* @major: The major number.
* This routine is thread safe and does not block.
*/
void devfs_dealloc_major (char type, int major)
{
int was_set;
struct major_list *list;
if (major < 0) return;
list = (type == DEVFS_SPECIAL_CHR) ? &char_major_list : &block_major_list;
spin_lock (&list->lock);
was_set = __test_and_clear_bit (major, list->bits);
spin_unlock (&list->lock);
if (!was_set) PRINTK ("(): major %d was already free\n", major);
} /* End Function devfs_dealloc_major */
EXPORT_SYMBOL(devfs_dealloc_major);
struct minor_list struct minor_list
{ {
...@@ -196,130 +162,110 @@ struct minor_list ...@@ -196,130 +162,110 @@ struct minor_list
struct minor_list *next; struct minor_list *next;
}; };
struct device_list static struct device_list {
{ struct minor_list *first;
struct minor_list *first, *last; struct minor_list *last;
int none_free; int none_free;
}; } block_list, char_list;
static DECLARE_MUTEX (block_semaphore); static DECLARE_MUTEX(device_list_mutex);
static struct device_list block_list;
static DECLARE_MUTEX (char_semaphore);
static struct device_list char_list;
/** /**
* devfs_alloc_devnum - Allocate a device number. * devfs_alloc_devnum - Allocate a device number.
* @type: The type (DEVFS_SPECIAL_CHR or DEVFS_SPECIAL_BLK). * @mode: The file mode (must be block device or character device).
* *
* Returns the allocated device number, else NODEV if none are available. * Returns the allocated device number, else NODEV if none are available.
* This routine is thread safe and may block. * This routine is thread safe and may block.
*/ */
dev_t devfs_alloc_devnum (char type) dev_t devfs_alloc_devnum(umode_t mode)
{ {
int minor;
struct semaphore *semaphore;
struct device_list *list; struct device_list *list;
struct major_list *major_list;
struct minor_list *entry; struct minor_list *entry;
int minor;
if (type == DEVFS_SPECIAL_CHR) if (S_ISCHR(mode)) {
{ major_list = &char_major_list;
semaphore = &char_semaphore;
list = &char_list; list = &char_list;
} } else {
else major_list = &block_major_list;
{
semaphore = &block_semaphore;
list = &block_list; list = &block_list;
} }
if (list->none_free) return 0; /* Fast test */
down (semaphore); down(&device_list_mutex);
if (list->none_free) if (list->none_free)
{ goto out_unlock;
up (semaphore);
return 0; for (entry = list->first; entry; entry = entry->next) {
}
for (entry = list->first; entry != NULL; entry = entry->next)
{
minor = find_first_zero_bit (entry->bits, 256); minor = find_first_zero_bit (entry->bits, 256);
if (minor >= 256) continue; if (minor >= 256)
__set_bit (minor, entry->bits); continue;
up (semaphore); goto out_done;
return MKDEV(entry->major, minor);
} }
/* Need to allocate a new major */ /* Need to allocate a new major */
if ( ( entry = kmalloc (sizeof *entry, GFP_KERNEL) ) == NULL ) entry = kmalloc (sizeof *entry, GFP_KERNEL);
{ if (!entry)
list->none_free = 1; goto out_full;
up (semaphore); memset(entry, 0, sizeof *entry);
return 0;
spin_lock(&major_list->lock);
entry->major = find_first_zero_bit(major_list->bits, 256);
if (entry->major >= 256) {
spin_unlock(&major_list->lock);
kfree(entry);
goto out_full;
} }
memset (entry, 0, sizeof *entry); __set_bit(entry->major, major_list->bits);
if ( ( entry->major = devfs_alloc_major (type) ) < 0 ) spin_unlock(&major_list->lock);
{
if (!list->first)
list->first = entry;
else
list->last->next = entry;
list->last = entry;
minor = 0;
out_done:
__set_bit(minor, entry->bits);
up(&device_list_mutex);
return MKDEV(entry->major, minor);
out_full:
list->none_free = 1; list->none_free = 1;
up (semaphore); out_unlock:
kfree (entry); up(&device_list_mutex);
return 0; return 0;
} }
__set_bit (0, entry->bits);
if (list->first == NULL) list->first = entry;
else list->last->next = entry;
list->last = entry;
up (semaphore);
return MKDEV(entry->major, 0);
} /* End Function devfs_alloc_devnum */
EXPORT_SYMBOL(devfs_alloc_devnum);
/** /**
* devfs_dealloc_devnum - Dellocate a device number. * devfs_dealloc_devnum - Dellocate a device number.
* @type: The type (DEVFS_SPECIAL_CHR or DEVFS_SPECIAL_BLK). * @mode: The file mode (must be block device or character device).
* @devnum: The device number. * @devnum: The device number.
* *
* This routine is thread safe and may block. * This routine is thread safe and may block.
*/ */
void devfs_dealloc_devnum (char type, dev_t devnum) void devfs_dealloc_devnum(umode_t mode, dev_t devnum)
{ {
int major, minor; struct device_list *list = S_ISCHR(mode) ? &char_list : &block_list;
struct semaphore *semaphore;
struct device_list *list;
struct minor_list *entry; struct minor_list *entry;
if (!devnum) return; if (!devnum)
if (type == DEVFS_SPECIAL_CHR)
{
semaphore = &char_semaphore;
list = &char_list;
}
else
{
semaphore = &block_semaphore;
list = &block_list;
}
major = MAJOR (devnum);
minor = MINOR (devnum);
down (semaphore);
for (entry = list->first; entry != NULL; entry = entry->next)
{
int was_set;
if (entry->major != major) continue;
was_set = __test_and_clear_bit (minor, entry->bits);
if (was_set) list->none_free = 0;
up (semaphore);
if (!was_set)
PRINTK ( "(): device %s was already free\n", kdevname (to_kdev_t(devnum)) );
return; return;
down(&device_list_mutex);
for (entry = list->first; entry; entry = entry->next) {
if (entry->major == MAJOR(devnum)) {
if (__test_and_clear_bit(MINOR(devnum), entry->bits))
list->none_free = 0;
break;
}
} }
up (semaphore); up(&device_list_mutex);
PRINTK ( "(): major for %s not previously allocated\n", }
kdevname (to_kdev_t(devnum)) );
} /* End Function devfs_dealloc_devnum */
EXPORT_SYMBOL(devfs_dealloc_devnum);
/** /**
......
...@@ -21,9 +21,6 @@ ...@@ -21,9 +21,6 @@
#define DEVFS_FL_DEFAULT DEVFS_FL_NONE #define DEVFS_FL_DEFAULT DEVFS_FL_NONE
#define DEVFS_SPECIAL_CHR 0
#define DEVFS_SPECIAL_BLK 1
typedef struct devfs_entry * devfs_handle_t; typedef struct devfs_entry * devfs_handle_t;
#ifdef CONFIG_DEVFS_FS #ifdef CONFIG_DEVFS_FS
...@@ -58,10 +55,6 @@ extern int devfs_set_file_size (devfs_handle_t de, unsigned long size); ...@@ -58,10 +55,6 @@ extern int devfs_set_file_size (devfs_handle_t de, unsigned long size);
extern int devfs_only (void); extern int devfs_only (void);
extern int devfs_register_tape (devfs_handle_t de); extern int devfs_register_tape (devfs_handle_t de);
extern void devfs_unregister_tape(int num); extern void devfs_unregister_tape(int num);
extern int devfs_alloc_major (char type);
extern void devfs_dealloc_major (char type, int major);
extern dev_t devfs_alloc_devnum (char type);
extern void devfs_dealloc_devnum (char type, dev_t devnum);
extern int devfs_alloc_unique_number (struct unique_numspace *space); extern int devfs_alloc_unique_number (struct unique_numspace *space);
extern void devfs_dealloc_unique_number (struct unique_numspace *space, extern void devfs_dealloc_unique_number (struct unique_numspace *space,
int number); int number);
...@@ -129,41 +122,18 @@ static inline int devfs_register_tape (devfs_handle_t de) ...@@ -129,41 +122,18 @@ static inline int devfs_register_tape (devfs_handle_t de)
static inline void devfs_unregister_tape(int num) static inline void devfs_unregister_tape(int num)
{ {
} }
static inline int devfs_alloc_major (char type)
{
return -1;
}
static inline void devfs_dealloc_major (char type, int major)
{
return;
}
static inline dev_t devfs_alloc_devnum (char type)
{
return 0;
}
static inline void devfs_dealloc_devnum (char type, dev_t devnum)
{
return;
}
static inline int devfs_alloc_unique_number (struct unique_numspace *space) static inline int devfs_alloc_unique_number (struct unique_numspace *space)
{ {
return -1; return -1;
} }
static inline void devfs_dealloc_unique_number (struct unique_numspace *space, static inline void devfs_dealloc_unique_number (struct unique_numspace *space,
int number) int number)
{ {
return; return;
} }
static inline void mount_devfs_fs (void) static inline void mount_devfs_fs (void)
{ {
return; return;
} }
#endif /* CONFIG_DEVFS_FS */ #endif /* CONFIG_DEVFS_FS */
#endif /* _LINUX_DEVFS_FS_KERNEL_H */ #endif /* _LINUX_DEVFS_FS_KERNEL_H */
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