From 7f7f25e82d54870df24d415a7007fbd327da027b Mon Sep 17 00:00:00 2001 From: Al Viro Date: Tue, 11 Feb 2014 17:49:24 -0500 Subject: [PATCH] replace checking for ->read/->aio_read presence with check in ->f_mode Since we are about to introduce new methods (read_iter/write_iter), the tests in a bunch of places would have to grow inconveniently. Check once (at open() time) and store results in ->f_mode as FMODE_CAN_READ and FMODE_CAN_WRITE resp. It might end up being a temporary measure - once everything switches from ->aio_{read,write} to ->{read,write}_iter it might make sense to return to open-coded checks. We'll see... Signed-off-by: Al Viro --- drivers/mtd/nand/nandsim.c | 4 ++-- drivers/usb/gadget/storage_common.c | 4 ++-- fs/file_table.c | 4 ++++ fs/open.c | 4 ++++ fs/read_write.c | 14 +++++++------- include/linux/fs.h | 4 ++++ 6 files changed, 23 insertions(+), 11 deletions(-) diff --git a/drivers/mtd/nand/nandsim.c b/drivers/mtd/nand/nandsim.c index 42e8a770e631..4f0d83648e5a 100644 --- a/drivers/mtd/nand/nandsim.c +++ b/drivers/mtd/nand/nandsim.c @@ -575,12 +575,12 @@ static int alloc_device(struct nandsim *ns) cfile = filp_open(cache_file, O_CREAT | O_RDWR | O_LARGEFILE, 0600); if (IS_ERR(cfile)) return PTR_ERR(cfile); - if (!cfile->f_op->read && !cfile->f_op->aio_read) { + if (!(cfile->f_mode & FMODE_CAN_READ)) { NS_ERR("alloc_device: cache file not readable\n"); err = -EINVAL; goto err_close; } - if (!cfile->f_op->write && !cfile->f_op->aio_write) { + if (!(cfile->f_mode & FMODE_CAN_WRITE)) { NS_ERR("alloc_device: cache file not writeable\n"); err = -EINVAL; goto err_close; diff --git a/drivers/usb/gadget/storage_common.c b/drivers/usb/gadget/storage_common.c index ec20a1f50c2d..a8898df131ed 100644 --- a/drivers/usb/gadget/storage_common.c +++ b/drivers/usb/gadget/storage_common.c @@ -220,11 +220,11 @@ int fsg_lun_open(struct fsg_lun *curlun, const char *filename) * If we can't read the file, it's no good. * If we can't write the file, use it read-only. */ - if (!(filp->f_op->read || filp->f_op->aio_read)) { + if (!(filp->f_mode & FMODE_CAN_READ)) { LINFO(curlun, "file not readable: %s\n", filename); goto out; } - if (!(filp->f_op->write || filp->f_op->aio_write)) + if (!(filp->f_mode & FMODE_CAN_WRITE)) ro = 1; size = i_size_read(inode->i_mapping->host); diff --git a/fs/file_table.c b/fs/file_table.c index a374f5033e97..be73cbc48c12 100644 --- a/fs/file_table.c +++ b/fs/file_table.c @@ -175,6 +175,10 @@ struct file *alloc_file(struct path *path, fmode_t mode, file->f_path = *path; file->f_inode = path->dentry->d_inode; file->f_mapping = path->dentry->d_inode->i_mapping; + if ((mode & FMODE_READ) && likely(fop->read || fop->aio_read)) + mode |= FMODE_CAN_READ; + if ((mode & FMODE_WRITE) && likely(fop->write || fop->aio_write)) + mode |= FMODE_CAN_WRITE; file->f_mode = mode; file->f_op = fop; if ((mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ) diff --git a/fs/open.c b/fs/open.c index 9d64679cec73..39d3d0468ee6 100644 --- a/fs/open.c +++ b/fs/open.c @@ -725,6 +725,10 @@ static int do_dentry_open(struct file *f, } if ((f->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ) i_readcount_inc(inode); + if ((f->f_mode & FMODE_READ) && likely(f->f_op->read || f->f_op->aio_read)) + f->f_mode |= FMODE_CAN_READ; + if ((f->f_mode & FMODE_WRITE) && likely(f->f_op->write || f->f_op->aio_write)) + f->f_mode |= FMODE_CAN_WRITE; f->f_flags &= ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC); diff --git a/fs/read_write.c b/fs/read_write.c index 31c6efa43183..d29d2a361d2c 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -396,7 +396,7 @@ ssize_t vfs_read(struct file *file, char __user *buf, size_t count, loff_t *pos) if (!(file->f_mode & FMODE_READ)) return -EBADF; - if (!file->f_op->read && !file->f_op->aio_read) + if (!(file->f_mode & FMODE_CAN_READ)) return -EINVAL; if (unlikely(!access_ok(VERIFY_WRITE, buf, count))) return -EFAULT; @@ -445,7 +445,7 @@ ssize_t __kernel_write(struct file *file, const char *buf, size_t count, loff_t const char __user *p; ssize_t ret; - if (!file->f_op->write && !file->f_op->aio_write) + if (!(file->f_mode & FMODE_CAN_WRITE)) return -EINVAL; old_fs = get_fs(); @@ -472,7 +472,7 @@ ssize_t vfs_write(struct file *file, const char __user *buf, size_t count, loff_ if (!(file->f_mode & FMODE_WRITE)) return -EBADF; - if (!file->f_op->write && !file->f_op->aio_write) + if (!(file->f_mode & FMODE_CAN_WRITE)) return -EINVAL; if (unlikely(!access_ok(VERIFY_READ, buf, count))) return -EFAULT; @@ -785,7 +785,7 @@ ssize_t vfs_readv(struct file *file, const struct iovec __user *vec, { if (!(file->f_mode & FMODE_READ)) return -EBADF; - if (!file->f_op->aio_read && !file->f_op->read) + if (!(file->f_mode & FMODE_CAN_READ)) return -EINVAL; return do_readv_writev(READ, file, vec, vlen, pos); @@ -798,7 +798,7 @@ ssize_t vfs_writev(struct file *file, const struct iovec __user *vec, { if (!(file->f_mode & FMODE_WRITE)) return -EBADF; - if (!file->f_op->aio_write && !file->f_op->write) + if (!(file->f_mode & FMODE_CAN_WRITE)) return -EINVAL; return do_readv_writev(WRITE, file, vec, vlen, pos); @@ -964,7 +964,7 @@ static size_t compat_readv(struct file *file, goto out; ret = -EINVAL; - if (!file->f_op->aio_read && !file->f_op->read) + if (!(file->f_mode & FMODE_CAN_READ)) goto out; ret = compat_do_readv_writev(READ, file, vec, vlen, pos); @@ -1041,7 +1041,7 @@ static size_t compat_writev(struct file *file, goto out; ret = -EINVAL; - if (!file->f_op->aio_write && !file->f_op->write) + if (!(file->f_mode & FMODE_CAN_WRITE)) goto out; ret = compat_do_readv_writev(WRITE, file, vec, vlen, pos); diff --git a/include/linux/fs.h b/include/linux/fs.h index 8153396d19b4..75eb71357adf 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -128,6 +128,10 @@ typedef void (dio_iodone_t)(struct kiocb *iocb, loff_t offset, #define FMODE_ATOMIC_POS ((__force fmode_t)0x8000) /* Write access to underlying fs */ #define FMODE_WRITER ((__force fmode_t)0x10000) +/* Has read method(s) */ +#define FMODE_CAN_READ ((__force fmode_t)0x20000) +/* Has write method(s) */ +#define FMODE_CAN_WRITE ((__force fmode_t)0x40000) /* File was opened by fanotify and shouldn't generate fanotify events */ #define FMODE_NONOTIFY ((__force fmode_t)0x1000000)