From bd2a31d522344b3ac2fb680bd2366e77a9bd8209 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Tue, 4 Mar 2014 14:54:22 -0500 Subject: [PATCH] get rid of fget_light() instead of returning the flags by reference, we can just have the low-level primitive return those in lower bits of unsigned long, with struct file * derived from the rest. Signed-off-by: Al Viro --- fs/file.c | 56 ++++++++++++++++++++++++++++++++++---------- fs/read_write.c | 16 +------------ include/linux/file.h | 21 +++++++++-------- include/linux/fs.h | 2 +- 4 files changed, 56 insertions(+), 39 deletions(-) diff --git a/fs/file.c b/fs/file.c index db25c2bdfe4..60a45e9f532 100644 --- a/fs/file.c +++ b/fs/file.c @@ -683,35 +683,65 @@ EXPORT_SYMBOL(fget_raw); * The fput_needed flag returned by fget_light should be passed to the * corresponding fput_light. */ -struct file *__fget_light(unsigned int fd, fmode_t mask, int *fput_needed) +static unsigned long __fget_light(unsigned int fd, fmode_t mask) { struct files_struct *files = current->files; struct file *file; - *fput_needed = 0; if (atomic_read(&files->count) == 1) { file = __fcheck_files(files, fd); - if (file && (file->f_mode & mask)) - file = NULL; + if (!file || unlikely(file->f_mode & mask)) + return 0; + return (unsigned long)file; } else { file = __fget(fd, mask); - if (file) - *fput_needed = 1; + if (!file) + return 0; + return FDPUT_FPUT | (unsigned long)file; } - - return file; } -struct file *fget_light(unsigned int fd, int *fput_needed) +unsigned long __fdget(unsigned int fd) { - return __fget_light(fd, FMODE_PATH, fput_needed); + return __fget_light(fd, FMODE_PATH); } -EXPORT_SYMBOL(fget_light); +EXPORT_SYMBOL(__fdget); -struct file *fget_raw_light(unsigned int fd, int *fput_needed) +unsigned long __fdget_raw(unsigned int fd) { - return __fget_light(fd, 0, fput_needed); + return __fget_light(fd, 0); +} + +unsigned long __fdget_pos(unsigned int fd) +{ + struct files_struct *files = current->files; + struct file *file; + unsigned long v; + + if (atomic_read(&files->count) == 1) { + file = __fcheck_files(files, fd); + v = 0; + } else { + file = __fget(fd, 0); + v = FDPUT_FPUT; + } + if (!file) + return 0; + + if (file->f_mode & FMODE_ATOMIC_POS) { + if (file_count(file) > 1) { + v |= FDPUT_POS_UNLOCK; + mutex_lock(&file->f_pos_lock); + } + } + return v | (unsigned long)file; } +/* + * We only lock f_pos if we have threads or if the file might be + * shared with another process. In both cases we'll have an elevated + * file count (done either by fdget() or by fork()). + */ + void set_close_on_exec(unsigned int fd, int flag) { struct files_struct *files = current->files; diff --git a/fs/read_write.c b/fs/read_write.c index 932bb3414a9..54e19b9392d 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -264,23 +264,9 @@ loff_t vfs_llseek(struct file *file, loff_t offset, int whence) } EXPORT_SYMBOL(vfs_llseek); -/* - * We only lock f_pos if we have threads or if the file might be - * shared with another process. In both cases we'll have an elevated - * file count (done either by fdget() or by fork()). - */ static inline struct fd fdget_pos(int fd) { - struct fd f = fdget(fd); - struct file *file = f.file; - - if (file && (file->f_mode & FMODE_ATOMIC_POS)) { - if (file_count(file) > 1) { - f.flags |= FDPUT_POS_UNLOCK; - mutex_lock(&file->f_pos_lock); - } - } - return f; + return __to_fd(__fdget_pos(fd)); } static inline void fdput_pos(struct fd f) diff --git a/include/linux/file.h b/include/linux/file.h index f2517fa2d61..4d69123377a 100644 --- a/include/linux/file.h +++ b/include/linux/file.h @@ -40,23 +40,24 @@ static inline void fdput(struct fd fd) } extern struct file *fget(unsigned int fd); -extern struct file *fget_light(unsigned int fd, int *fput_needed); +extern struct file *fget_raw(unsigned int fd); +extern unsigned long __fdget(unsigned int fd); +extern unsigned long __fdget_raw(unsigned int fd); +extern unsigned long __fdget_pos(unsigned int fd); -static inline struct fd fdget(unsigned int fd) +static inline struct fd __to_fd(unsigned long v) { - int b; - struct file *f = fget_light(fd, &b); - return (struct fd){f,b}; + return (struct fd){(struct file *)(v & ~3),v & 3}; } -extern struct file *fget_raw(unsigned int fd); -extern struct file *fget_raw_light(unsigned int fd, int *fput_needed); +static inline struct fd fdget(unsigned int fd) +{ + return __to_fd(__fdget(fd)); +} static inline struct fd fdget_raw(unsigned int fd) { - int b; - struct file *f = fget_raw_light(fd, &b); - return (struct fd){f,b}; + return __to_fd(__fdget_raw(fd)); } extern int f_dupfd(unsigned int from, struct file *file, unsigned flags); diff --git a/include/linux/fs.h b/include/linux/fs.h index ebfde04bca0..23b2a35d712 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -812,7 +812,7 @@ struct file { #ifdef CONFIG_DEBUG_WRITECOUNT unsigned long f_mnt_write_state; #endif -}; +} __attribute__((aligned(4))); /* lest something weird decides that 2 is OK */ struct file_handle { __u32 handle_bytes; -- 2.43.2