| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * linux/fs/seq_file.c |
| * |
| * helper functions for making synthetic files from sequences of records. |
| * initial implementation -- AV, Oct 2001. |
| */ |
| |
| #include <linux/fs.h> |
| #include <linux/export.h> |
| #include <linux/seq_file.h> |
| #include <linux/vmalloc.h> |
| #include <linux/slab.h> |
| #include <linux/cred.h> |
| #include <linux/mm.h> |
| #include <linux/printk.h> |
| #include <linux/string_helpers.h> |
| |
| #include <linux/uaccess.h> |
| #include <asm/page.h> |
| |
| static void seq_set_overflow(struct seq_file *m) |
| { |
| m->count = m->size; |
| } |
| |
| static void *seq_buf_alloc(unsigned long size) |
| { |
| return kvmalloc(size, GFP_KERNEL); |
| } |
| |
| /** |
| * seq_open - initialize sequential file |
| * @file: file we initialize |
| * @op: method table describing the sequence |
| * |
| * seq_open() sets @file, associating it with a sequence described |
| * by @op. @op->start() sets the iterator up and returns the first |
| * element of sequence. @op->stop() shuts it down. @op->next() |
| * returns the next element of sequence. @op->show() prints element |
| * into the buffer. In case of error ->start() and ->next() return |
| * ERR_PTR(error). In the end of sequence they return %NULL. ->show() |
| * returns 0 in case of success and negative number in case of error. |
| * Returning SEQ_SKIP means "discard this element and move on". |
| * Note: seq_open() will allocate a struct seq_file and store its |
| * pointer in @file->private_data. This pointer should not be modified. |
| */ |
| int seq_open(struct file *file, const struct seq_operations *op) |
| { |
| struct seq_file *p; |
| |
| WARN_ON(file->private_data); |
| |
| p = kzalloc(sizeof(*p), GFP_KERNEL); |
| if (!p) |
| return -ENOMEM; |
| |
| file->private_data = p; |
| |
| mutex_init(&p->lock); |
| p->op = op; |
| |
| // No refcounting: the lifetime of 'p' is constrained |
| // to the lifetime of the file. |
| p->file = file; |
| |
| /* |
| * Wrappers around seq_open(e.g. swaps_open) need to be |
| * aware of this. If they set f_version themselves, they |
| * should call seq_open first and then set f_version. |
| */ |
| file->f_version = 0; |
| |
| /* |
| * seq_files support lseek() and pread(). They do not implement |
| * write() at all, but we clear FMODE_PWRITE here for historical |
| * reasons. |
| * |
| * If a client of seq_files a) implements file.write() and b) wishes to |
| * support pwrite() then that client will need to implement its own |
| * file.open() which calls seq_open() and then sets FMODE_PWRITE. |
| */ |
| file->f_mode &= ~FMODE_PWRITE; |
| return 0; |
| } |
| EXPORT_SYMBOL(seq_open); |
| |
| static int traverse(struct seq_file *m, loff_t offset) |
| { |
| loff_t pos = 0, index; |
| int error = 0; |
| void *p; |
| |
| m->version = 0; |
| index = 0; |
| m->count = m->from = 0; |
| if (!offset) { |
| m->index = index; |
| return 0; |
| } |
| if (!m->buf) { |
| m->buf = seq_buf_alloc(m->size = PAGE_SIZE); |
| if (!m->buf) |
| return -ENOMEM; |
| } |
| p = m->op->start(m, &index); |
| while (p) { |
| error = PTR_ERR(p); |
| if (IS_ERR(p)) |
| break; |
| error = m->op->show(m, p); |
| if (error < 0) |
| break; |
| if (unlikely(error)) { |
| error = 0; |
| m->count = 0; |
| } |
| if (seq_has_overflowed(m)) |
| goto Eoverflow; |
| if (pos + m->count > offset) { |
| m->from = offset - pos; |
| m->count -= m->from; |
| m->index = index; |
| break; |
| } |
| pos += m->count; |
| m->count = 0; |
| if (pos == offset) { |
| index++; |
| m->index = index; |
| break; |
| } |
| p = m->op->next(m, p, &index); |
| } |
| m->op->stop(m, p); |
| m->index = index; |
| return error; |
| |
| Eoverflow: |
| m->op->stop(m, p); |
| kvfree(m->buf); |
| m->count = 0; |
| m->buf = seq_buf_alloc(m->size <<= 1); |
| return !m->buf ? -ENOMEM : -EAGAIN; |
| } |
| |
| /** |
| * seq_read - ->read() method for sequential files. |
| * @file: the file to read from |
| * @buf: the buffer to read to |
| * @size: the maximum number of bytes to read |
| * @ppos: the current position in the file |
| * |
| * Ready-made ->f_op->read() |
| */ |
| ssize_t seq_read(struct file *file, char __user *buf, size_t size, loff_t *ppos) |
| { |
| struct seq_file *m = file->private_data; |
| size_t copied = 0; |
| loff_t pos; |
| size_t n; |
| void *p; |
| int err = 0; |
| |
| mutex_lock(&m->lock); |
| |
| /* |
| * seq_file->op->..m_start/m_stop/m_next may do special actions |
| * or optimisations based on the file->f_version, so we want to |
| * pass the file->f_version to those methods. |
| * |
| * seq_file->version is just copy of f_version, and seq_file |
| * methods can treat it simply as file version. |
| * It is copied in first and copied out after all operations. |
| * It is convenient to have it as part of structure to avoid the |
| * need of passing another argument to all the seq_file methods. |
| */ |
| m->version = file->f_version; |
| |
| /* |
| * if request is to read from zero offset, reset iterator to first |
| * record as it might have been already advanced by previous requests |
| */ |
| if (*ppos == 0) { |
| m->index = 0; |
| m->version = 0; |
| m->count = 0; |
| } |
| |
| /* Don't assume *ppos is where we left it */ |
| if (unlikely(*ppos != m->read_pos)) { |
| while ((err = traverse(m, *ppos)) == -EAGAIN) |
| ; |
| if (err) { |
| /* With prejudice... */ |
| m->read_pos = 0; |
| m->version = 0; |
| m->index = 0; |
| m->count = 0; |
| goto Done; |
| } else { |
| m->read_pos = *ppos; |
| } |
| } |
| |
| /* grab buffer if we didn't have one */ |
| if (!m->buf) { |
| m->buf = seq_buf_alloc(m->size = PAGE_SIZE); |
| if (!m->buf) |
| goto Enomem; |
| } |
| /* if not empty - flush it first */ |
| if (m->count) { |
| n = min(m->count, size); |
| err = copy_to_user(buf, m->buf + m->from, n); |
| if (err) |
| goto Efault; |
| m->count -= n; |
| m->from += n; |
| size -= n; |
| buf += n; |
| copied += n; |
| if (!m->count) { |
| m->from = 0; |
| m->index++; |
| } |
| if (!size) |
| goto Done; |
| } |
| /* we need at least one record in buffer */ |
| pos = m->index; |
| p = m->op->start(m, &pos); |
| while (1) { |
| err = PTR_ERR(p); |
| if (!p || IS_ERR(p)) |
| break; |
| err = m->op->show(m, p); |
| if (err < 0) |
| break; |
| if (unlikely(err)) |
| m->count = 0; |
| if (unlikely(!m->count)) { |
| p = m->op->next(m, p, &pos); |
| m->index = pos; |
| continue; |
| } |
| if (m->count < m->size) |
| goto Fill; |
| m->op->stop(m, p); |
| kvfree(m->buf); |
| m->count = 0; |
| m->buf = seq_buf_alloc(m->size <<= 1); |
| if (!m->buf) |
| goto Enomem; |
| m->version = 0; |
| pos = m->index; |
| p = m->op->start(m, &pos); |
| } |
| m->op->stop(m, p); |
| m->count = 0; |
| goto Done; |
| Fill: |
| /* they want more? let's try to get some more */ |
| while (m->count < size) { |
| size_t offs = m->count; |
| loff_t next = pos; |
| p = m->op->next(m, p, &next); |
| if (!p || IS_ERR(p)) { |
| err = PTR_ERR(p); |
| break; |
| } |
| err = m->op->show(m, p); |
| if (seq_has_overflowed(m) || err) { |
| m->count = offs; |
| if (likely(err <= 0)) |
| break; |
| } |
| pos = next; |
| } |
| m->op->stop(m, p); |
| n = min(m->count, size); |
| err = copy_to_user(buf, m->buf, n); |
| if (err) |
| goto Efault; |
| copied += n; |
| m->count -= n; |
| if (m->count) |
| m->from = n; |
| else |
| pos++; |
| m->index = pos; |
| Done: |
| if (!copied) |
| copied = err; |
| else { |
| *ppos += copied; |
| m->read_pos += copied; |
| } |
| file->f_version = m->version; |
| mutex_unlock(&m->lock); |
| return copied; |
| Enomem: |
| err = -ENOMEM; |
| goto Done; |
| Efault: |
| err = -EFAULT; |
| goto Done; |
| } |
| EXPORT_SYMBOL(seq_read); |
| |
| /** |
| * seq_lseek - ->llseek() method for sequential files. |
| * @file: the file in question |
| * @offset: new position |
| * @whence: 0 for absolute, 1 for relative position |
| * |
| * Ready-made ->f_op->llseek() |
| */ |
| loff_t seq_lseek(struct file *file, loff_t offset, int whence) |
| { |
| struct seq_file *m = file->private_data; |
| loff_t retval = -EINVAL; |
| |
| mutex_lock(&m->lock); |
| m->version = file->f_version; |
| switch (whence) { |
| case SEEK_CUR: |
| offset += file->f_pos; |
| case SEEK_SET: |
| if (offset < 0) |
| break; |
| retval = offset; |
| if (offset != m->read_pos) { |
| while ((retval = traverse(m, offset)) == -EAGAIN) |
| ; |
| if (retval) { |
| /* with extreme prejudice... */ |
| file->f_pos = 0; |
| m->read_pos = 0; |
| m->version = 0; |
| m->index = 0; |
| m->count = 0; |
| } else { |
| m->read_pos = offset; |
| retval = file->f_pos = offset; |
| } |
| } else { |
| file->f_pos = offset; |
| } |
| } |
| file->f_version = m->version; |
| mutex_unlock(&m->lock); |
| return retval; |
| } |
| EXPORT_SYMBOL(seq_lseek); |
| |
| /** |
| * seq_release - free the structures associated with sequential file. |
| * @file: file in question |
| * @inode: its inode |
| * |
| * Frees the structures associated with sequential file; can be used |
| * as ->f_op->release() if you don't have private data to destroy. |
| */ |
| int seq_release(struct inode *inode, struct file *file) |
| { |
| struct seq_file *m = file->private_data; |
| kvfree(m->buf); |
| kfree(m); |
| return 0; |
| } |
| EXPORT_SYMBOL(seq_release); |
| |
| /** |
| * seq_escape - print string into buffer, escaping some characters |
| * @m: target buffer |
| * @s: string |
| * @esc: set of characters that need escaping |
| * |
| * Puts string into buffer, replacing each occurrence of character from |
| * @esc with usual octal escape. |
| * Use seq_has_overflowed() to check for errors. |
| */ |
| void seq_escape(struct seq_file *m, const char *s, const char *esc) |
| { |
| char *buf; |
| size_t size = seq_get_buf(m, &buf); |
| int ret; |
| |
| ret = string_escape_str(s, buf, size, ESCAPE_OCTAL, esc); |
| seq_commit(m, ret < size ? ret : -1); |
| } |
| EXPORT_SYMBOL(seq_escape); |
| |
| void seq_vprintf(struct seq_file *m, const char *f, va_list args) |
| { |
| int len; |
| |
| if (m->count < m->size) { |
| len = vsnprintf(m->buf + m->count, m->size - m->count, f, args); |
| if (m->count + len < m->size) { |
| m->count += len; |
| return; |
| } |
| } |
| seq_set_overflow(m); |
| } |
| EXPORT_SYMBOL(seq_vprintf); |
| |
| void seq_printf(struct seq_file *m, const char *f, ...) |
| { |
| va_list args; |
| |
| va_start(args, f); |
| seq_vprintf(m, f, args); |
| va_end(args); |
| } |
| EXPORT_SYMBOL(seq_printf); |
| |
| /** |
| * mangle_path - mangle and copy path to buffer beginning |
| * @s: buffer start |
| * @p: beginning of path in above buffer |
| * @esc: set of characters that need escaping |
| * |
| * Copy the path from @p to @s, replacing each occurrence of character from |
| * @esc with usual octal escape. |
| * Returns pointer past last written character in @s, or NULL in case of |
| * failure. |
| */ |
| char *mangle_path(char *s, const char *p, const char *esc) |
| { |
| while (s <= p) { |
| char c = *p++; |
| if (!c) { |
| return s; |
| } else if (!strchr(esc, c)) { |
| *s++ = c; |
| } else if (s + 4 > p) { |
| break; |
| } else { |
| *s++ = '\\'; |
| *s++ = '0' + ((c & 0300) >> 6); |
| *s++ = '0' + ((c & 070) >> 3); |
| *s++ = '0' + (c & 07); |
| } |
| } |
| return NULL; |
| } |
| EXPORT_SYMBOL(mangle_path); |
| |
| /** |
| * seq_path - seq_file interface to print a pathname |
| * @m: the seq_file handle |
| * @path: the struct path to print |
| * @esc: set of characters to escape in the output |
| * |
| * return the absolute path of 'path', as represented by the |
| * dentry / mnt pair in the path parameter. |
| */ |
| int seq_path(struct seq_file *m, const struct path *path, const char *esc) |
| { |
| char *buf; |
| size_t size = seq_get_buf(m, &buf); |
| int res = -1; |
| |
| if (size) { |
| char *p = d_path(path, buf, size); |
| if (!IS_ERR(p)) { |
| char *end = mangle_path(buf, p, esc); |
| if (end) |
| res = end - buf; |
| } |
| } |
| seq_commit(m, res); |
| |
| return res; |
| } |
| EXPORT_SYMBOL(seq_path); |
| |
| /** |
| * seq_file_path - seq_file interface to print a pathname of a file |
| * @m: the seq_file handle |
| * @file: the struct file to print |
| * @esc: set of characters to escape in the output |
| * |
| * return the absolute path to the file. |
| */ |
| int seq_file_path(struct seq_file *m, struct file *file, const char *esc) |
| { |
| return seq_path(m, &file->f_path, esc); |
| } |
| EXPORT_SYMBOL(seq_file_path); |
| |
| /* |
| * Same as seq_path, but relative to supplied root. |
| */ |
| int seq_path_root(struct seq_file *m, const struct path *path, |
| const struct path *root, const char *esc) |
| { |
| char *buf; |
| size_t size = seq_get_buf(m, &buf); |
| int res = -ENAMETOOLONG; |
| |
| if (size) { |
| char *p; |
| |
| p = __d_path(path, root, buf, size); |
| if (!p) |
| return SEQ_SKIP; |
| res = PTR_ERR(p); |
| if (!IS_ERR(p)) { |
| char *end = mangle_path(buf, p, esc); |
| if (end) |
| res = end - buf; |
| else |
| res = -ENAMETOOLONG; |
| } |
| } |
| seq_commit(m, res); |
| |
| return res < 0 && res != -ENAMETOOLONG ? res : 0; |
| } |
| |
| /* |
| * returns the path of the 'dentry' from the root of its filesystem. |
| */ |
| int seq_dentry(struct seq_file *m, struct dentry *dentry, const char *esc) |
| { |
| char *buf; |
| size_t size = seq_get_buf(m, &buf); |
| int res = -1; |
| |
| if (size) { |
| char *p = dentry_path(dentry, buf, size); |
| if (!IS_ERR(p)) { |
| char *end = mangle_path(buf, p, esc); |
| if (end) |
| res = end - buf; |
| } |
| } |
| seq_commit(m, res); |
| |
| return res; |
| } |
| EXPORT_SYMBOL(seq_dentry); |
| |
| static void *single_start(struct seq_file *p, loff_t *pos) |
| { |
| return NULL + (*pos == 0); |
| } |
| |
| static void *single_next(struct seq_file *p, void *v, loff_t *pos) |
| { |
| ++*pos; |
| return NULL; |
| } |
| |
| static void single_stop(struct seq_file *p, void *v) |
| { |
| } |
| |
| int single_open(struct file *file, int (*show)(struct seq_file *, void *), |
| void *data) |
| { |
| struct seq_operations *op = kmalloc(sizeof(*op), GFP_KERNEL); |
| int res = -ENOMEM; |
| |
| if (op) { |
| op->start = single_start; |
| op->next = single_next; |
| op->stop = single_stop; |
| op->show = show; |
| res = seq_open(file, op); |
| if (!res) |
| ((struct seq_file *)file->private_data)->private = data; |
| else |
| kfree(op); |
| } |
| return res; |
| } |
| EXPORT_SYMBOL(single_open); |
| |
| int single_open_size(struct file *file, int (*show)(struct seq_file *, void *), |
| void *data, size_t size) |
| { |
| char *buf = seq_buf_alloc(size); |
| int ret; |
| if (!buf) |
| return -ENOMEM; |
| ret = single_open(file, show, data); |
| if (ret) { |
| kvfree(buf); |
| return ret; |
| } |
| ((struct seq_file *)file->private_data)->buf = buf; |
| ((struct seq_file *)file->private_data)->size = size; |
| return 0; |
| } |
| EXPORT_SYMBOL(single_open_size); |
| |
| int single_release(struct inode *inode, struct file *file) |
| { |
| const struct seq_operations *op = ((struct seq_file *)file->private_data)->op; |
| int res = seq_release(inode, file); |
| kfree(op); |
| return res; |
| } |
| EXPORT_SYMBOL(single_release); |
| |
| int seq_release_private(struct inode *inode, struct file *file) |
| { |
| struct seq_file *seq = file->private_data; |
| |
| kfree(seq->private); |
| seq->private = NULL; |
| return seq_release(inode, file); |
| } |
| EXPORT_SYMBOL(seq_release_private); |
| |
| void *__seq_open_private(struct file *f, const struct seq_operations *ops, |
| int psize) |
| { |
| int rc; |
| void *private; |
| struct seq_file *seq; |
| |
| private = kzalloc(psize, GFP_KERNEL); |
| if (private == NULL) |
| goto out; |
| |
| rc = seq_open(f, ops); |
| if (rc < 0) |
| goto out_free; |
| |
| seq = f->private_data; |
| seq->private = private; |
| return private; |
| |
| out_free: |
| kfree(private); |
| out: |
| return NULL; |
| } |
| EXPORT_SYMBOL(__seq_open_private); |
| |
| int seq_open_private(struct file *filp, const struct seq_operations *ops, |
| int psize) |
| { |
| return __seq_open_private(filp, ops, psize) ? 0 : -ENOMEM; |
| } |
| EXPORT_SYMBOL(seq_open_private); |
| |
| void seq_putc(struct seq_file *m, char c) |
| { |
| if (m->count >= m->size) |
| return; |
| |
| m->buf[m->count++] = c; |
| } |
| EXPORT_SYMBOL(seq_putc); |
| |
| void seq_puts(struct seq_file *m, const char *s) |
| { |
| int len = strlen(s); |
| |
| if (m->count + len >= m->size) { |
| seq_set_overflow(m); |
| return; |
| } |
| memcpy(m->buf + m->count, s, len); |
| m->count += len; |
| } |
| EXPORT_SYMBOL(seq_puts); |
| |
| /** |
| * A helper routine for putting decimal numbers without rich format of printf(). |
| * only 'unsigned long long' is supported. |
| * @m: seq_file identifying the buffer to which data should be written |
| * @delimiter: a string which is printed before the number |
| * @num: the number |
| * @width: a minimum field width |
| * |
| * This routine will put strlen(delimiter) + number into seq_filed. |
| * This routine is very quick when you show lots of numbers. |
| * In usual cases, it will be better to use seq_printf(). It's easier to read. |
| */ |
| void seq_put_decimal_ull_width(struct seq_file *m, const char *delimiter, |
| unsigned long long num, unsigned int width) |
| { |
| int len; |
| |
| if (m->count + 2 >= m->size) /* we'll write 2 bytes at least */ |
| goto overflow; |
| |
| if (delimiter && delimiter[0]) { |
| if (delimiter[1] == 0) |
| seq_putc(m, delimiter[0]); |
| else |
| seq_puts(m, delimiter); |
| } |
| |
| if (!width) |
| width = 1; |
| |
| if (m->count + width >= m->size) |
| goto overflow; |
| |
| if (num < 10) { |
| m->buf[m->count++] = num + '0'; |
| return; |
| } |
| |
| len = num_to_str(m->buf + m->count, m->size - m->count, num, width); |
| if (!len) |
| goto overflow; |
| |
| m->count += len; |
| return; |
| |
| overflow: |
| seq_set_overflow(m); |
| } |
| |
| void seq_put_decimal_ull(struct seq_file *m, const char *delimiter, |
| unsigned long long num) |
| { |
| return seq_put_decimal_ull_width(m, delimiter, num, 0); |
| } |
| EXPORT_SYMBOL(seq_put_decimal_ull); |
| |
| /** |
| * seq_put_hex_ll - put a number in hexadecimal notation |
| * @m: seq_file identifying the buffer to which data should be written |
| * @delimiter: a string which is printed before the number |
| * @v: the number |
| * @width: a minimum field width |
| * |
| * seq_put_hex_ll(m, "", v, 8) is equal to seq_printf(m, "%08llx", v) |
| * |
| * This routine is very quick when you show lots of numbers. |
| * In usual cases, it will be better to use seq_printf(). It's easier to read. |
| */ |
| void seq_put_hex_ll(struct seq_file *m, const char *delimiter, |
| unsigned long long v, unsigned int width) |
| { |
| unsigned int len; |
| int i; |
| |
| if (delimiter && delimiter[0]) { |
| if (delimiter[1] == 0) |
| seq_putc(m, delimiter[0]); |
| else |
| seq_puts(m, delimiter); |
| } |
| |
| /* If x is 0, the result of __builtin_clzll is undefined */ |
| if (v == 0) |
| len = 1; |
| else |
| len = (sizeof(v) * 8 - __builtin_clzll(v) + 3) / 4; |
| |
| if (len < width) |
| len = width; |
| |
| if (m->count + len > m->size) { |
| seq_set_overflow(m); |
| return; |
| } |
| |
| for (i = len - 1; i >= 0; i--) { |
| m->buf[m->count + i] = hex_asc[0xf & v]; |
| v = v >> 4; |
| } |
| m->count += len; |
| } |
| |
| void seq_put_decimal_ll(struct seq_file *m, const char *delimiter, long long num) |
| { |
| int len; |
| |
| if (m->count + 3 >= m->size) /* we'll write 2 bytes at least */ |
| goto overflow; |
| |
| if (delimiter && delimiter[0]) { |
| if (delimiter[1] == 0) |
| seq_putc(m, delimiter[0]); |
| else |
| seq_puts(m, delimiter); |
| } |
| |
| if (m->count + 2 >= m->size) |
| goto overflow; |
| |
| if (num < 0) { |
| m->buf[m->count++] = '-'; |
| num = -num; |
| } |
| |
| if (num < 10) { |
| m->buf[m->count++] = num + '0'; |
| return; |
| } |
| |
| len = num_to_str(m->buf + m->count, m->size - m->count, num, 0); |
| if (!len) |
| goto overflow; |
| |
| m->count += len; |
| return; |
| |
| overflow: |
| seq_set_overflow(m); |
| } |
| EXPORT_SYMBOL(seq_put_decimal_ll); |
| |
| /** |
| * seq_write - write arbitrary data to buffer |
| * @seq: seq_file identifying the buffer to which data should be written |
| * @data: data address |
| * @len: number of bytes |
| * |
| * Return 0 on success, non-zero otherwise. |
| */ |
| int seq_write(struct seq_file *seq, const void *data, size_t len) |
| { |
| if (seq->count + len < seq->size) { |
| memcpy(seq->buf + seq->count, data, len); |
| seq->count += len; |
| return 0; |
| } |
| seq_set_overflow(seq); |
| return -1; |
| } |
| EXPORT_SYMBOL(seq_write); |
| |
| /** |
| * seq_pad - write padding spaces to buffer |
| * @m: seq_file identifying the buffer to which data should be written |
| * @c: the byte to append after padding if non-zero |
| */ |
| void seq_pad(struct seq_file *m, char c) |
| { |
| int size = m->pad_until - m->count; |
| if (size > 0) { |
| if (size + m->count > m->size) { |
| seq_set_overflow(m); |
| return; |
| } |
| memset(m->buf + m->count, ' ', size); |
| m->count += size; |
| } |
| if (c) |
| seq_putc(m, c); |
| } |
| EXPORT_SYMBOL(seq_pad); |
| |
| /* A complete analogue of print_hex_dump() */ |
| void seq_hex_dump(struct seq_file *m, const char *prefix_str, int prefix_type, |
| int rowsize, int groupsize, const void *buf, size_t len, |
| bool ascii) |
| { |
| const u8 *ptr = buf; |
| int i, linelen, remaining = len; |
| char *buffer; |
| size_t size; |
| int ret; |
| |
| if (rowsize != 16 && rowsize != 32) |
| rowsize = 16; |
| |
| for (i = 0; i < len && !seq_has_overflowed(m); i += rowsize) { |
| linelen = min(remaining, rowsize); |
| remaining -= rowsize; |
| |
| switch (prefix_type) { |
| case DUMP_PREFIX_ADDRESS: |
| seq_printf(m, "%s%p: ", prefix_str, ptr + i); |
| break; |
| case DUMP_PREFIX_OFFSET: |
| seq_printf(m, "%s%.8x: ", prefix_str, i); |
| break; |
| default: |
| seq_printf(m, "%s", prefix_str); |
| break; |
| } |
| |
| size = seq_get_buf(m, &buffer); |
| ret = hex_dump_to_buffer(ptr + i, linelen, rowsize, groupsize, |
| buffer, size, ascii); |
| seq_commit(m, ret < size ? ret : -1); |
| |
| seq_putc(m, '\n'); |
| } |
| } |
| EXPORT_SYMBOL(seq_hex_dump); |
| |
| struct list_head *seq_list_start(struct list_head *head, loff_t pos) |
| { |
| struct list_head *lh; |
| |
| list_for_each(lh, head) |
| if (pos-- == 0) |
| return lh; |
| |
| return NULL; |
| } |
| EXPORT_SYMBOL(seq_list_start); |
| |
| struct list_head *seq_list_start_head(struct list_head *head, loff_t pos) |
| { |
| if (!pos) |
| return head; |
| |
| return seq_list_start(head, pos - 1); |
| } |
| EXPORT_SYMBOL(seq_list_start_head); |
| |
| struct list_head *seq_list_next(void *v, struct list_head *head, loff_t *ppos) |
| { |
| struct list_head *lh; |
| |
| lh = ((struct list_head *)v)->next; |
| ++*ppos; |
| return lh == head ? NULL : lh; |
| } |
| EXPORT_SYMBOL(seq_list_next); |
| |
| /** |
| * seq_hlist_start - start an iteration of a hlist |
| * @head: the head of the hlist |
| * @pos: the start position of the sequence |
| * |
| * Called at seq_file->op->start(). |
| */ |
| struct hlist_node *seq_hlist_start(struct hlist_head *head, loff_t pos) |
| { |
| struct hlist_node *node; |
| |
| hlist_for_each(node, head) |
| if (pos-- == 0) |
| return node; |
| return NULL; |
| } |
| EXPORT_SYMBOL(seq_hlist_start); |
| |
| /** |
| * seq_hlist_start_head - start an iteration of a hlist |
| * @head: the head of the hlist |
| * @pos: the start position of the sequence |
| * |
| * Called at seq_file->op->start(). Call this function if you want to |
| * print a header at the top of the output. |
| */ |
| struct hlist_node *seq_hlist_start_head(struct hlist_head *head, loff_t pos) |
| { |
| if (!pos) |
| return SEQ_START_TOKEN; |
| |
| return seq_hlist_start(head, pos - 1); |
| } |
| EXPORT_SYMBOL(seq_hlist_start_head); |
| |
| /** |
| * seq_hlist_next - move to the next position of the hlist |
| * @v: the current iterator |
| * @head: the head of the hlist |
| * @ppos: the current position |
| * |
| * Called at seq_file->op->next(). |
| */ |
| struct hlist_node *seq_hlist_next(void *v, struct hlist_head *head, |
| loff_t *ppos) |
| { |
| struct hlist_node *node = v; |
| |
| ++*ppos; |
| if (v == SEQ_START_TOKEN) |
| return head->first; |
| else |
| return node->next; |
| } |
| EXPORT_SYMBOL(seq_hlist_next); |
| |
| /** |
| * seq_hlist_start_rcu - start an iteration of a hlist protected by RCU |
| * @head: the head of the hlist |
| * @pos: the start position of the sequence |
| * |
| * Called at seq_file->op->start(). |
| * |
| * This list-traversal primitive may safely run concurrently with |
| * the _rcu list-mutation primitives such as hlist_add_head_rcu() |
| * as long as the traversal is guarded by rcu_read_lock(). |
| */ |
| struct hlist_node *seq_hlist_start_rcu(struct hlist_head *head, |
| loff_t pos) |
| { |
| struct hlist_node *node; |
| |
| __hlist_for_each_rcu(node, head) |
| if (pos-- == 0) |
| return node; |
| return NULL; |
| } |
| EXPORT_SYMBOL(seq_hlist_start_rcu); |
| |
| /** |
| * seq_hlist_start_head_rcu - start an iteration of a hlist protected by RCU |
| * @head: the head of the hlist |
| * @pos: the start position of the sequence |
| * |
| * Called at seq_file->op->start(). Call this function if you want to |
| * print a header at the top of the output. |
| * |
| * This list-traversal primitive may safely run concurrently with |
| * the _rcu list-mutation primitives such as hlist_add_head_rcu() |
| * as long as the traversal is guarded by rcu_read_lock(). |
| */ |
| struct hlist_node *seq_hlist_start_head_rcu(struct hlist_head *head, |
| loff_t pos) |
| { |
| if (!pos) |
| return SEQ_START_TOKEN; |
| |
| return seq_hlist_start_rcu(head, pos - 1); |
| } |
| EXPORT_SYMBOL(seq_hlist_start_head_rcu); |
| |
| /** |
| * seq_hlist_next_rcu - move to the next position of the hlist protected by RCU |
| * @v: the current iterator |
| * @head: the head of the hlist |
| * @ppos: the current position |
| * |
| * Called at seq_file->op->next(). |
| * |
| * This list-traversal primitive may safely run concurrently with |
| * the _rcu list-mutation primitives such as hlist_add_head_rcu() |
| * as long as the traversal is guarded by rcu_read_lock(). |
| */ |
| struct hlist_node *seq_hlist_next_rcu(void *v, |
| struct hlist_head *head, |
| loff_t *ppos) |
| { |
| struct hlist_node *node = v; |
| |
| ++*ppos; |
| if (v == SEQ_START_TOKEN) |
| return rcu_dereference(head->first); |
| else |
| return rcu_dereference(node->next); |
| } |
| EXPORT_SYMBOL(seq_hlist_next_rcu); |
| |
| /** |
| * seq_hlist_start_precpu - start an iteration of a percpu hlist array |
| * @head: pointer to percpu array of struct hlist_heads |
| * @cpu: pointer to cpu "cursor" |
| * @pos: start position of sequence |
| * |
| * Called at seq_file->op->start(). |
| */ |
| struct hlist_node * |
| seq_hlist_start_percpu(struct hlist_head __percpu *head, int *cpu, loff_t pos) |
| { |
| struct hlist_node *node; |
| |
| for_each_possible_cpu(*cpu) { |
| hlist_for_each(node, per_cpu_ptr(head, *cpu)) { |
| if (pos-- == 0) |
| return node; |
| } |
| } |
| return NULL; |
| } |
| EXPORT_SYMBOL(seq_hlist_start_percpu); |
| |
| /** |
| * seq_hlist_next_percpu - move to the next position of the percpu hlist array |
| * @v: pointer to current hlist_node |
| * @head: pointer to percpu array of struct hlist_heads |
| * @cpu: pointer to cpu "cursor" |
| * @pos: start position of sequence |
| * |
| * Called at seq_file->op->next(). |
| */ |
| struct hlist_node * |
| seq_hlist_next_percpu(void *v, struct hlist_head __percpu *head, |
| int *cpu, loff_t *pos) |
| { |
| struct hlist_node *node = v; |
| |
| ++*pos; |
| |
| if (node->next) |
| return node->next; |
| |
| for (*cpu = cpumask_next(*cpu, cpu_possible_mask); *cpu < nr_cpu_ids; |
| *cpu = cpumask_next(*cpu, cpu_possible_mask)) { |
| struct hlist_head *bucket = per_cpu_ptr(head, *cpu); |
| |
| if (!hlist_empty(bucket)) |
| return bucket->first; |
| } |
| return NULL; |
| } |
| EXPORT_SYMBOL(seq_hlist_next_percpu); |