From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx> Subject: seq_file: remove m->version The process maps file was the only user of version (introduced back in 2005). Now that it uses ppos instead, we can remove it. Link: http://lkml.kernel.org/r/20200317193201.9924-4-adobriyan@xxxxxxxxx Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> Signed-off-by: Alexey Dobriyan <adobriyan@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/seq_file.c | 28 ---------------------------- include/linux/seq_file.h | 1 - 2 files changed, 29 deletions(-) --- a/fs/seq_file.c~seq_file-remove-m-version +++ a/fs/seq_file.c @@ -68,13 +68,6 @@ int seq_open(struct file *file, const st 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. @@ -94,7 +87,6 @@ static int traverse(struct seq_file *m, int error = 0; void *p; - m->version = 0; m->index = 0; m->count = m->from = 0; if (!offset) @@ -161,25 +153,11 @@ ssize_t seq_read(struct file *file, char 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; } @@ -190,7 +168,6 @@ ssize_t seq_read(struct file *file, char if (err) { /* With prejudice... */ m->read_pos = 0; - m->version = 0; m->index = 0; m->count = 0; goto Done; @@ -243,7 +220,6 @@ ssize_t seq_read(struct file *file, char m->buf = seq_buf_alloc(m->size <<= 1); if (!m->buf) goto Enomem; - m->version = 0; p = m->op->start(m, &m->index); } m->op->stop(m, p); @@ -287,7 +263,6 @@ Done: *ppos += copied; m->read_pos += copied; } - file->f_version = m->version; mutex_unlock(&m->lock); return copied; Enomem: @@ -313,7 +288,6 @@ loff_t seq_lseek(struct file *file, loff loff_t retval = -EINVAL; mutex_lock(&m->lock); - m->version = file->f_version; switch (whence) { case SEEK_CUR: offset += file->f_pos; @@ -329,7 +303,6 @@ loff_t seq_lseek(struct file *file, loff /* with extreme prejudice... */ file->f_pos = 0; m->read_pos = 0; - m->version = 0; m->index = 0; m->count = 0; } else { @@ -340,7 +313,6 @@ loff_t seq_lseek(struct file *file, loff file->f_pos = offset; } } - file->f_version = m->version; mutex_unlock(&m->lock); return retval; } --- a/include/linux/seq_file.h~seq_file-remove-m-version +++ a/include/linux/seq_file.h @@ -21,7 +21,6 @@ struct seq_file { size_t pad_until; loff_t index; loff_t read_pos; - u64 version; struct mutex lock; const struct seq_operations *op; int poll_event; _
