linux-stable/include/linux/seq_file.h
Linus Torvalds ed2d265d12 The following text was taken from the original review request:
"[RFC - PATCH 0/7] consolidation of BUG support code."
 		https://lkml.org/lkml/2012/1/26/525
 --
 
 The changes shown here are to unify linux's BUG support under
 the one <linux/bug.h> file.  Due to historical reasons, we have
 some BUG code in bug.h and some in kernel.h -- i.e. the support for
 BUILD_BUG in linux/kernel.h predates the addition of linux/bug.h,
 but old code in kernel.h wasn't moved to bug.h at that time.  As
 a band-aid, kernel.h was including <asm/bug.h> to pseudo link them.
 
 This has caused confusion[1] and general yuck/WTF[2] reactions.
 Here is an example that violates the principle of least surprise:
 
       CC      lib/string.o
       lib/string.c: In function 'strlcat':
       lib/string.c:225:2: error: implicit declaration of function 'BUILD_BUG_ON'
       make[2]: *** [lib/string.o] Error 1
       $
       $ grep linux/bug.h lib/string.c
       #include <linux/bug.h>
       $
 
 We've included <linux/bug.h> for the BUG infrastructure and yet we
 still get a compile fail!  [We've not kernel.h for BUILD_BUG_ON.]
 Ugh - very confusing for someone who is new to kernel development.
 
 With the above in mind, the goals of this changeset are:
 
 1) find and fix any include/*.h files that were relying on the
    implicit presence of BUG code.
 2) find and fix any C files that were consuming kernel.h and
    hence relying on implicitly getting some/all BUG code.
 3) Move the BUG related code living in kernel.h to <linux/bug.h>
 4) remove the asm/bug.h from kernel.h to finally break the chain.
 
 During development, the order was more like 3-4, build-test, 1-2.
 But to ensure that git history for bisect doesn't get needless
 build failures introduced, the commits have been reorderd to fix
 the problem areas in advance.
 
 [1]  https://lkml.org/lkml/2012/1/3/90
 [2]  https://lkml.org/lkml/2012/1/17/414
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Merge tag 'bug-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux

Pull <linux/bug.h> cleanup from Paul Gortmaker:
 "The changes shown here are to unify linux's BUG support under the one
  <linux/bug.h> file.  Due to historical reasons, we have some BUG code
  in bug.h and some in kernel.h -- i.e.  the support for BUILD_BUG in
  linux/kernel.h predates the addition of linux/bug.h, but old code in
  kernel.h wasn't moved to bug.h at that time.  As a band-aid, kernel.h
  was including <asm/bug.h> to pseudo link them.

  This has caused confusion[1] and general yuck/WTF[2] reactions.  Here
  is an example that violates the principle of least surprise:

      CC      lib/string.o
      lib/string.c: In function 'strlcat':
      lib/string.c:225:2: error: implicit declaration of function 'BUILD_BUG_ON'
      make[2]: *** [lib/string.o] Error 1
      $
      $ grep linux/bug.h lib/string.c
      #include <linux/bug.h>
      $

  We've included <linux/bug.h> for the BUG infrastructure and yet we
  still get a compile fail! [We've not kernel.h for BUILD_BUG_ON.] Ugh -
  very confusing for someone who is new to kernel development.

  With the above in mind, the goals of this changeset are:

  1) find and fix any include/*.h files that were relying on the
     implicit presence of BUG code.
  2) find and fix any C files that were consuming kernel.h and hence
     relying on implicitly getting some/all BUG code.
  3) Move the BUG related code living in kernel.h to <linux/bug.h>
  4) remove the asm/bug.h from kernel.h to finally break the chain.

  During development, the order was more like 3-4, build-test, 1-2.  But
  to ensure that git history for bisect doesn't get needless build
  failures introduced, the commits have been reorderd to fix the problem
  areas in advance.

	[1]  https://lkml.org/lkml/2012/1/3/90
	[2]  https://lkml.org/lkml/2012/1/17/414"

Fix up conflicts (new radeon file, reiserfs header cleanups) as per Paul
and linux-next.

* tag 'bug-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux:
  kernel.h: doesn't explicitly use bug.h, so don't include it.
  bug: consolidate BUILD_BUG_ON with other bug code
  BUG: headers with BUG/BUG_ON etc. need linux/bug.h
  bug.h: add include of it to various implicit C users
  lib: fix implicit users of kernel.h for TAINT_WARN
  spinlock: macroize assert_spin_locked to avoid bug.h dependency
  x86: relocate get/set debugreg fcns to include/asm/debugreg.
2012-03-24 10:08:39 -07:00

160 lines
4.6 KiB
C

#ifndef _LINUX_SEQ_FILE_H
#define _LINUX_SEQ_FILE_H
#include <linux/types.h>
#include <linux/string.h>
#include <linux/bug.h>
#include <linux/mutex.h>
#include <linux/cpumask.h>
#include <linux/nodemask.h>
struct seq_operations;
struct file;
struct path;
struct inode;
struct dentry;
struct seq_file {
char *buf;
size_t size;
size_t from;
size_t count;
loff_t index;
loff_t read_pos;
u64 version;
struct mutex lock;
const struct seq_operations *op;
int poll_event;
void *private;
};
struct seq_operations {
void * (*start) (struct seq_file *m, loff_t *pos);
void (*stop) (struct seq_file *m, void *v);
void * (*next) (struct seq_file *m, void *v, loff_t *pos);
int (*show) (struct seq_file *m, void *v);
};
#define SEQ_SKIP 1
/**
* seq_get_buf - get buffer to write arbitrary data to
* @m: the seq_file handle
* @bufp: the beginning of the buffer is stored here
*
* Return the number of bytes available in the buffer, or zero if
* there's no space.
*/
static inline size_t seq_get_buf(struct seq_file *m, char **bufp)
{
BUG_ON(m->count > m->size);
if (m->count < m->size)
*bufp = m->buf + m->count;
else
*bufp = NULL;
return m->size - m->count;
}
/**
* seq_commit - commit data to the buffer
* @m: the seq_file handle
* @num: the number of bytes to commit
*
* Commit @num bytes of data written to a buffer previously acquired
* by seq_buf_get. To signal an error condition, or that the data
* didn't fit in the available space, pass a negative @num value.
*/
static inline void seq_commit(struct seq_file *m, int num)
{
if (num < 0) {
m->count = m->size;
} else {
BUG_ON(m->count + num > m->size);
m->count += num;
}
}
char *mangle_path(char *s, const char *p, const char *esc);
int seq_open(struct file *, const struct seq_operations *);
ssize_t seq_read(struct file *, char __user *, size_t, loff_t *);
loff_t seq_lseek(struct file *, loff_t, int);
int seq_release(struct inode *, struct file *);
int seq_escape(struct seq_file *, const char *, const char *);
int seq_putc(struct seq_file *m, char c);
int seq_puts(struct seq_file *m, const char *s);
int seq_write(struct seq_file *seq, const void *data, size_t len);
__printf(2, 3) int seq_printf(struct seq_file *, const char *, ...);
int seq_path(struct seq_file *, const struct path *, const char *);
int seq_dentry(struct seq_file *, struct dentry *, const char *);
int seq_path_root(struct seq_file *m, const struct path *path,
const struct path *root, const char *esc);
int seq_bitmap(struct seq_file *m, const unsigned long *bits,
unsigned int nr_bits);
static inline int seq_cpumask(struct seq_file *m, const struct cpumask *mask)
{
return seq_bitmap(m, cpumask_bits(mask), nr_cpu_ids);
}
static inline int seq_nodemask(struct seq_file *m, nodemask_t *mask)
{
return seq_bitmap(m, mask->bits, MAX_NUMNODES);
}
int seq_bitmap_list(struct seq_file *m, const unsigned long *bits,
unsigned int nr_bits);
static inline int seq_cpumask_list(struct seq_file *m,
const struct cpumask *mask)
{
return seq_bitmap_list(m, cpumask_bits(mask), nr_cpu_ids);
}
static inline int seq_nodemask_list(struct seq_file *m, nodemask_t *mask)
{
return seq_bitmap_list(m, mask->bits, MAX_NUMNODES);
}
int single_open(struct file *, int (*)(struct seq_file *, void *), void *);
int single_release(struct inode *, struct file *);
void *__seq_open_private(struct file *, const struct seq_operations *, int);
int seq_open_private(struct file *, const struct seq_operations *, int);
int seq_release_private(struct inode *, struct file *);
int seq_put_decimal_ull(struct seq_file *m, char delimiter,
unsigned long long num);
int seq_put_decimal_ll(struct seq_file *m, char delimiter,
long long num);
#define SEQ_START_TOKEN ((void *)1)
/*
* Helpers for iteration over list_head-s in seq_files
*/
extern struct list_head *seq_list_start(struct list_head *head,
loff_t pos);
extern struct list_head *seq_list_start_head(struct list_head *head,
loff_t pos);
extern struct list_head *seq_list_next(void *v, struct list_head *head,
loff_t *ppos);
/*
* Helpers for iteration over hlist_head-s in seq_files
*/
extern struct hlist_node *seq_hlist_start(struct hlist_head *head,
loff_t pos);
extern struct hlist_node *seq_hlist_start_head(struct hlist_head *head,
loff_t pos);
extern struct hlist_node *seq_hlist_next(void *v, struct hlist_head *head,
loff_t *ppos);
extern struct hlist_node *seq_hlist_start_rcu(struct hlist_head *head,
loff_t pos);
extern struct hlist_node *seq_hlist_start_head_rcu(struct hlist_head *head,
loff_t pos);
extern struct hlist_node *seq_hlist_next_rcu(void *v,
struct hlist_head *head,
loff_t *ppos);
#endif