From b6aeadeda22a9aa322fdfcd3f4c69ccf0da5cbdd Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Fri, 9 Sep 2005 13:10:30 -0700 Subject: [PATCH] FUSE - file operations This patch adds the file operations of FUSE. The following operations are added: o open o flush o release o fsync o readpage o commit_write Signed-off-by: Miklos Szeredi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/fuse/file.c | 341 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 341 insertions(+) create mode 100644 fs/fuse/file.c (limited to 'fs/fuse/file.c') diff --git a/fs/fuse/file.c b/fs/fuse/file.c new file mode 100644 index 00000000000..de8c9c70246 --- /dev/null +++ b/fs/fuse/file.c @@ -0,0 +1,341 @@ +/* + FUSE: Filesystem in Userspace + Copyright (C) 2001-2005 Miklos Szeredi + + This program can be distributed under the terms of the GNU GPL. + See the file COPYING. +*/ + +#include "fuse_i.h" + +#include +#include +#include + +static int fuse_open(struct inode *inode, struct file *file) +{ + struct fuse_conn *fc = get_fuse_conn(inode); + struct fuse_req *req; + struct fuse_open_in inarg; + struct fuse_open_out outarg; + struct fuse_file *ff; + int err; + /* Restarting the syscall is not allowed if O_CREAT and O_EXCL + are both set, because creation will fail on the restart */ + int excl = (file->f_flags & (O_CREAT|O_EXCL)) == (O_CREAT|O_EXCL); + + err = generic_file_open(inode, file); + if (err) + return err; + + /* If opening the root node, no lookup has been performed on + it, so the attributes must be refreshed */ + if (get_node_id(inode) == FUSE_ROOT_ID) { + int err = fuse_do_getattr(inode); + if (err) + return err; + } + + if (excl) + req = fuse_get_request_nonint(fc); + else + req = fuse_get_request(fc); + if (!req) + return excl ? -EINTR : -ERESTARTSYS; + + err = -ENOMEM; + ff = kmalloc(sizeof(struct fuse_file), GFP_KERNEL); + if (!ff) + goto out_put_request; + + ff->release_req = fuse_request_alloc(); + if (!ff->release_req) { + kfree(ff); + goto out_put_request; + } + + memset(&inarg, 0, sizeof(inarg)); + inarg.flags = file->f_flags & ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC); + req->in.h.opcode = FUSE_OPEN; + req->in.h.nodeid = get_node_id(inode); + req->inode = inode; + req->in.numargs = 1; + req->in.args[0].size = sizeof(inarg); + req->in.args[0].value = &inarg; + req->out.numargs = 1; + req->out.args[0].size = sizeof(outarg); + req->out.args[0].value = &outarg; + if (excl) + request_send_nonint(fc, req); + else + request_send(fc, req); + err = req->out.h.error; + if (!err) + invalidate_inode_pages(inode->i_mapping); + if (err) { + fuse_request_free(ff->release_req); + kfree(ff); + } else { + ff->fh = outarg.fh; + file->private_data = ff; + } + + out_put_request: + fuse_put_request(fc, req); + return err; +} + +static int fuse_release(struct inode *inode, struct file *file) +{ + struct fuse_conn *fc = get_fuse_conn(inode); + struct fuse_file *ff = file->private_data; + struct fuse_req *req = ff->release_req; + struct fuse_release_in *inarg = &req->misc.release_in; + + inarg->fh = ff->fh; + inarg->flags = file->f_flags & ~O_EXCL; + req->in.h.opcode = FUSE_RELEASE; + req->in.h.nodeid = get_node_id(inode); + req->inode = inode; + req->in.numargs = 1; + req->in.args[0].size = sizeof(struct fuse_release_in); + req->in.args[0].value = inarg; + request_send_background(fc, req); + kfree(ff); + + /* Return value is ignored by VFS */ + return 0; +} + +static int fuse_flush(struct file *file) +{ + struct inode *inode = file->f_dentry->d_inode; + struct fuse_conn *fc = get_fuse_conn(inode); + struct fuse_file *ff = file->private_data; + struct fuse_req *req; + struct fuse_flush_in inarg; + int err; + + if (fc->no_flush) + return 0; + + req = fuse_get_request_nonint(fc); + if (!req) + return -EINTR; + + memset(&inarg, 0, sizeof(inarg)); + inarg.fh = ff->fh; + req->in.h.opcode = FUSE_FLUSH; + req->in.h.nodeid = get_node_id(inode); + req->inode = inode; + req->file = file; + req->in.numargs = 1; + req->in.args[0].size = sizeof(inarg); + req->in.args[0].value = &inarg; + request_send_nonint(fc, req); + err = req->out.h.error; + fuse_put_request(fc, req); + if (err == -ENOSYS) { + fc->no_flush = 1; + err = 0; + } + return err; +} + +static int fuse_fsync(struct file *file, struct dentry *de, int datasync) +{ + struct inode *inode = de->d_inode; + struct fuse_conn *fc = get_fuse_conn(inode); + struct fuse_file *ff = file->private_data; + struct fuse_req *req; + struct fuse_fsync_in inarg; + int err; + + if (fc->no_fsync) + return 0; + + req = fuse_get_request(fc); + if (!req) + return -ERESTARTSYS; + + memset(&inarg, 0, sizeof(inarg)); + inarg.fh = ff->fh; + inarg.fsync_flags = datasync ? 1 : 0; + req->in.h.opcode = FUSE_FSYNC; + req->in.h.nodeid = get_node_id(inode); + req->inode = inode; + req->file = file; + req->in.numargs = 1; + req->in.args[0].size = sizeof(inarg); + req->in.args[0].value = &inarg; + request_send(fc, req); + err = req->out.h.error; + fuse_put_request(fc, req); + if (err == -ENOSYS) { + fc->no_fsync = 1; + err = 0; + } + return err; +} + +static ssize_t fuse_send_read(struct fuse_req *req, struct file *file, + struct inode *inode, loff_t pos, size_t count) +{ + struct fuse_conn *fc = get_fuse_conn(inode); + struct fuse_file *ff = file->private_data; + struct fuse_read_in inarg; + + memset(&inarg, 0, sizeof(struct fuse_read_in)); + inarg.fh = ff->fh; + inarg.offset = pos; + inarg.size = count; + req->in.h.opcode = FUSE_READ; + req->in.h.nodeid = get_node_id(inode); + req->inode = inode; + req->file = file; + req->in.numargs = 1; + req->in.args[0].size = sizeof(struct fuse_read_in); + req->in.args[0].value = &inarg; + req->out.argpages = 1; + req->out.argvar = 1; + req->out.numargs = 1; + req->out.args[0].size = count; + request_send_nonint(fc, req); + return req->out.args[0].size; +} + +static int fuse_readpage(struct file *file, struct page *page) +{ + struct inode *inode = page->mapping->host; + struct fuse_conn *fc = get_fuse_conn(inode); + loff_t pos = (loff_t) page->index << PAGE_CACHE_SHIFT; + struct fuse_req *req = fuse_get_request_nonint(fc); + int err = -EINTR; + if (!req) + goto out; + + req->out.page_zeroing = 1; + req->num_pages = 1; + req->pages[0] = page; + fuse_send_read(req, file, inode, pos, PAGE_CACHE_SIZE); + err = req->out.h.error; + fuse_put_request(fc, req); + if (!err) + SetPageUptodate(page); + out: + unlock_page(page); + return err; +} + +static ssize_t fuse_send_write(struct fuse_req *req, struct file *file, + struct inode *inode, loff_t pos, size_t count) +{ + struct fuse_conn *fc = get_fuse_conn(inode); + struct fuse_file *ff = file->private_data; + struct fuse_write_in inarg; + struct fuse_write_out outarg; + + memset(&inarg, 0, sizeof(struct fuse_write_in)); + inarg.fh = ff->fh; + inarg.offset = pos; + inarg.size = count; + req->in.h.opcode = FUSE_WRITE; + req->in.h.nodeid = get_node_id(inode); + req->inode = inode; + req->file = file; + req->in.argpages = 1; + req->in.numargs = 2; + req->in.args[0].size = sizeof(struct fuse_write_in); + req->in.args[0].value = &inarg; + req->in.args[1].size = count; + req->out.numargs = 1; + req->out.args[0].size = sizeof(struct fuse_write_out); + req->out.args[0].value = &outarg; + request_send_nonint(fc, req); + return outarg.size; +} + +static int fuse_prepare_write(struct file *file, struct page *page, + unsigned offset, unsigned to) +{ + /* No op */ + return 0; +} + +static int fuse_commit_write(struct file *file, struct page *page, + unsigned offset, unsigned to) +{ + int err; + ssize_t nres; + unsigned count = to - offset; + struct inode *inode = page->mapping->host; + struct fuse_conn *fc = get_fuse_conn(inode); + loff_t pos = ((loff_t) page->index << PAGE_CACHE_SHIFT) + offset; + struct fuse_req *req = fuse_get_request_nonint(fc); + if (!req) + return -EINTR; + + req->num_pages = 1; + req->pages[0] = page; + req->page_offset = offset; + nres = fuse_send_write(req, file, inode, pos, count); + err = req->out.h.error; + fuse_put_request(fc, req); + if (!err && nres != count) + err = -EIO; + if (!err) { + pos += count; + if (pos > i_size_read(inode)) + i_size_write(inode, pos); + + if (offset == 0 && to == PAGE_CACHE_SIZE) { + clear_page_dirty(page); + SetPageUptodate(page); + } + } else if (err == -EINTR || err == -EIO) + fuse_invalidate_attr(inode); + return err; +} + +static int fuse_file_mmap(struct file *file, struct vm_area_struct *vma) +{ + if ((vma->vm_flags & VM_SHARED)) { + if ((vma->vm_flags & VM_WRITE)) + return -ENODEV; + else + vma->vm_flags &= ~VM_MAYWRITE; + } + return generic_file_mmap(file, vma); +} + +static int fuse_set_page_dirty(struct page *page) +{ + printk("fuse_set_page_dirty: should not happen\n"); + dump_stack(); + return 0; +} + +static struct file_operations fuse_file_operations = { + .llseek = generic_file_llseek, + .read = generic_file_read, + .write = generic_file_write, + .mmap = fuse_file_mmap, + .open = fuse_open, + .flush = fuse_flush, + .release = fuse_release, + .fsync = fuse_fsync, + .sendfile = generic_file_sendfile, +}; + +static struct address_space_operations fuse_file_aops = { + .readpage = fuse_readpage, + .prepare_write = fuse_prepare_write, + .commit_write = fuse_commit_write, + .set_page_dirty = fuse_set_page_dirty, +}; + +void fuse_init_file_inode(struct inode *inode) +{ + inode->i_fop = &fuse_file_operations; + inode->i_data.a_ops = &fuse_file_aops; +} -- cgit v1.2.3