static struct file *__dentry_open(struct dentry *dentry, struct vfsmount *mnt, struct file *f, int (*open)(struct inode *, struct file *), const struct cred *cred) { static const struct file_operations empty_fops = {}; struct inode *inode; int error; f->f_mode = OPEN_FMODE(f->f_flags) | FMODE_LSEEK | FMODE_PREAD | FMODE_PWRITE; if (unlikely(f->f_flags & O_PATH)) f->f_mode = FMODE_PATH; inode = dentry->d_inode; if (f->f_mode & FMODE_WRITE) { error = __get_file_write_access(inode, mnt); if (error) goto cleanup_file; if (!special_file(inode->i_mode)) file_take_write(f); } f->f_mapping = inode->i_mapping; f->f_path.dentry = dentry; f->f_path.mnt = mnt; f->f_pos = 0; file_sb_list_add(f, inode->i_sb); if (unlikely(f->f_mode & FMODE_PATH)) { f->f_op = &empty_fops; return f; } f->f_op = fops_get(inode->i_fop); error = security_dentry_open(f, cred); if (error) goto cleanup_all; error = break_lease(inode, f->f_flags); if (error) goto cleanup_all; if (!open && f->f_op) open = f->f_op->open; if (open) { error = open(inode, f); if (error) goto cleanup_all; } if ((f->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ) i_readcount_inc(inode); f->f_flags &= ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC); file_ra_state_init(&f->f_ra, f->f_mapping->host->i_mapping); /* NB: we're sure to have correct a_ops only after f_op->open */ if (f->f_flags & O_DIRECT) { if (!f->f_mapping->a_ops || ((!f->f_mapping->a_ops->direct_IO) && (!f->f_mapping->a_ops->get_xip_mem))) { fput(f); f = ERR_PTR(-EINVAL); } } return f; cleanup_all: fops_put(f->f_op); if (f->f_mode & FMODE_WRITE) { put_write_access(inode); if (!special_file(inode->i_mode)) { /* * We don't consider this a real * mnt_want/drop_write() pair * because it all happenend right * here, so just reset the state. */ file_reset_write(f); mnt_drop_write(mnt); } } file_sb_list_del(f); f->f_path.dentry = NULL; f->f_path.mnt = NULL; cleanup_file: put_filp(f); dput(dentry); mntput(mnt); return ERR_PTR(error); }
static int do_dentry_open(struct file *f, int (*open)(struct inode *, struct file *), const struct cred *cred) { static const struct file_operations empty_fops = {}; struct inode *inode; int error; f->f_mode = OPEN_FMODE(f->f_flags) | FMODE_LSEEK | FMODE_PREAD | FMODE_PWRITE; if (unlikely(f->f_flags & O_PATH)) f->f_mode = FMODE_PATH; path_get(&f->f_path); inode = f->f_inode = f->f_path.dentry->d_inode; if (f->f_mode & FMODE_WRITE) { error = __get_file_write_access(inode, f->f_path.mnt); if (error) goto cleanup_file; if (!special_file(inode->i_mode)) file_take_write(f); } f->f_mapping = inode->i_mapping; file_sb_list_add(f, inode->i_sb); if (unlikely(f->f_mode & FMODE_PATH)) { f->f_op = &empty_fops; return 0; } f->f_op = fops_get(inode->i_fop); error = security_file_open(f, cred); if (error) goto cleanup_all; error = break_lease(inode, f->f_flags); if (error) goto cleanup_all; if (!open && f->f_op) open = f->f_op->open; if (open) { error = open(inode, f); if (error) goto cleanup_all; } if ((f->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ) i_readcount_inc(inode); f->f_flags &= ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC); file_ra_state_init(&f->f_ra, f->f_mapping->host->i_mapping); return 0; cleanup_all: fops_put(f->f_op); file_sb_list_del(f); if (f->f_mode & FMODE_WRITE) { put_write_access(inode); if (!special_file(inode->i_mode)) { /* * We don't consider this a real * mnt_want/drop_write() pair * because it all happenend right * here, so just reset the state. */ file_reset_write(f); __mnt_drop_write(f->f_path.mnt); } } cleanup_file: path_put(&f->f_path); f->f_path.mnt = NULL; f->f_path.dentry = NULL; f->f_inode = NULL; return error; }
static int do_dentry_open(struct file *f, int (*open)(struct inode *, struct file *), const struct cred *cred) { static const struct file_operations empty_fops = {}; struct inode *inode; int error; f->f_mode = OPEN_FMODE(f->f_flags) | FMODE_LSEEK | FMODE_PREAD | FMODE_PWRITE; path_get(&f->f_path); inode = f->f_inode = f->f_path.dentry->d_inode; f->f_mapping = inode->i_mapping; if (unlikely(f->f_flags & O_PATH)) { f->f_mode = FMODE_PATH; f->f_op = &empty_fops; return 0; } if (f->f_mode & FMODE_WRITE && !special_file(inode->i_mode)) { error = get_write_access(inode); if (unlikely(error)) goto cleanup_file; error = __mnt_want_write(f->f_path.mnt); if (unlikely(error)) { put_write_access(inode); goto cleanup_file; } f->f_mode |= FMODE_WRITER; } /* POSIX.1-2008/SUSv4 Section XSI 2.9.7 */ if (S_ISREG(inode->i_mode)) f->f_mode |= FMODE_ATOMIC_POS; f->f_op = fops_get(inode->i_fop); if (unlikely(WARN_ON(!f->f_op))) { error = -ENODEV; goto cleanup_all; } error = security_file_open(f, cred); if (error) goto cleanup_all; error = break_lease(inode, f->f_flags); if (error) goto cleanup_all; if (!open) open = f->f_op->open; if (open) { error = open(inode, f); if (error) goto cleanup_all; } 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_op->read_iter)) f->f_mode |= FMODE_CAN_READ; if ((f->f_mode & FMODE_WRITE) && likely(f->f_op->write || f->f_op->aio_write || f->f_op->write_iter)) f->f_mode |= FMODE_CAN_WRITE; f->f_flags &= ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC); file_ra_state_init(&f->f_ra, f->f_mapping->host->i_mapping); return 0; cleanup_all: fops_put(f->f_op); if (f->f_mode & FMODE_WRITER) { put_write_access(inode); __mnt_drop_write(f->f_path.mnt); } cleanup_file: path_put(&f->f_path); f->f_path.mnt = NULL; f->f_path.dentry = NULL; f->f_inode = NULL; return error; }