| /* |
| * file.c |
| * |
| * Copyright (C) 1995, 1996, 1997 by Paal-Kr. Engstad and Volker Lendecke |
| * Copyright (C) 1997 by Volker Lendecke |
| * |
| * Please add a note about your changes to smbfs in the ChangeLog file. |
| */ |
| |
| #include <linux/time.h> |
| #include <linux/kernel.h> |
| #include <linux/errno.h> |
| #include <linux/fcntl.h> |
| #include <linux/stat.h> |
| #include <linux/mm.h> |
| #include <linux/slab.h> |
| #include <linux/pagemap.h> |
| #include <linux/smp_lock.h> |
| #include <linux/net.h> |
| |
| #include <asm/uaccess.h> |
| #include <asm/system.h> |
| |
| #include <linux/smbno.h> |
| #include <linux/smb_fs.h> |
| |
| #include "smb_debug.h" |
| #include "proto.h" |
| |
| static int |
| smb_fsync(struct file *file, struct dentry * dentry, int datasync) |
| { |
| struct smb_sb_info *server = server_from_dentry(dentry); |
| int result; |
| |
| VERBOSE("sync file %s/%s\n", DENTRY_PATH(dentry)); |
| |
| /* |
| * The VFS will writepage() all dirty pages for us, but we |
| * should send a SMBflush to the server, letting it know that |
| * we want things synchronized with actual storage. |
| * |
| * Note: this function requires all pages to have been written already |
| * (should be ok with writepage_sync) |
| */ |
| result = smb_proc_flush(server, SMB_I(dentry->d_inode)->fileid); |
| return result; |
| } |
| |
| /* |
| * Read a page synchronously. |
| */ |
| static int |
| smb_readpage_sync(struct dentry *dentry, struct page *page) |
| { |
| char *buffer = kmap(page); |
| loff_t offset = (loff_t)page->index << PAGE_CACHE_SHIFT; |
| struct smb_sb_info *server = server_from_dentry(dentry); |
| unsigned int rsize = smb_get_rsize(server); |
| int count = PAGE_SIZE; |
| int result; |
| |
| VERBOSE("file %s/%s, count=%d@%Ld, rsize=%d\n", |
| DENTRY_PATH(dentry), count, offset, rsize); |
| |
| result = smb_open(dentry, SMB_O_RDONLY); |
| if (result < 0) |
| goto io_error; |
| |
| do { |
| if (count < rsize) |
| rsize = count; |
| |
| result = server->ops->read(dentry->d_inode,offset,rsize,buffer); |
| if (result < 0) |
| goto io_error; |
| |
| count -= result; |
| offset += result; |
| buffer += result; |
| dentry->d_inode->i_atime = |
| current_fs_time(dentry->d_inode->i_sb); |
| if (result < rsize) |
| break; |
| } while (count); |
| |
| memset(buffer, 0, count); |
| flush_dcache_page(page); |
| SetPageUptodate(page); |
| result = 0; |
| |
| io_error: |
| kunmap(page); |
| unlock_page(page); |
| return result; |
| } |
| |
| /* |
| * We are called with the page locked and we unlock it when done. |
| */ |
| static int |
| smb_readpage(struct file *file, struct page *page) |
| { |
| int error; |
| struct dentry *dentry = file->f_dentry; |
| |
| page_cache_get(page); |
| error = smb_readpage_sync(dentry, page); |
| page_cache_release(page); |
| return error; |
| } |
| |
| /* |
| * Write a page synchronously. |
| * Offset is the data offset within the page. |
| */ |
| static int |
| smb_writepage_sync(struct inode *inode, struct page *page, |
| unsigned long pageoffset, unsigned int count) |
| { |
| loff_t offset; |
| char *buffer = kmap(page) + pageoffset; |
| struct smb_sb_info *server = server_from_inode(inode); |
| unsigned int wsize = smb_get_wsize(server); |
| int ret = 0; |
| |
| offset = ((loff_t)page->index << PAGE_CACHE_SHIFT) + pageoffset; |
| VERBOSE("file ino=%ld, fileid=%d, count=%d@%Ld, wsize=%d\n", |
| inode->i_ino, SMB_I(inode)->fileid, count, offset, wsize); |
| |
| do { |
| int write_ret; |
| |
| if (count < wsize) |
| wsize = count; |
| |
| write_ret = server->ops->write(inode, offset, wsize, buffer); |
| if (write_ret < 0) { |
| PARANOIA("failed write, wsize=%d, write_ret=%d\n", |
| wsize, write_ret); |
| ret = write_ret; |
| break; |
| } |
| /* N.B. what if result < wsize?? */ |
| #ifdef SMBFS_PARANOIA |
| if (write_ret < wsize) |
| PARANOIA("short write, wsize=%d, write_ret=%d\n", |
| wsize, write_ret); |
| #endif |
| buffer += wsize; |
| offset += wsize; |
| count -= wsize; |
| /* |
| * Update the inode now rather than waiting for a refresh. |
| */ |
| inode->i_mtime = inode->i_atime = current_fs_time(inode->i_sb); |
| SMB_I(inode)->flags |= SMB_F_LOCALWRITE; |
| if (offset > inode->i_size) |
| inode->i_size = offset; |
| } while (count); |
| |
| kunmap(page); |
| return ret; |
| } |
| |
| /* |
| * Write a page to the server. This will be used for NFS swapping only |
| * (for now), and we currently do this synchronously only. |
| * |
| * We are called with the page locked and we unlock it when done. |
| */ |
| static int |
| smb_writepage(struct page *page, struct writeback_control *wbc) |
| { |
| struct address_space *mapping = page->mapping; |
| struct inode *inode; |
| unsigned long end_index; |
| unsigned offset = PAGE_CACHE_SIZE; |
| int err; |
| |
| if (!mapping) |
| BUG(); |
| inode = mapping->host; |
| if (!inode) |
| BUG(); |
| |
| end_index = inode->i_size >> PAGE_CACHE_SHIFT; |
| |
| /* easy case */ |
| if (page->index < end_index) |
| goto do_it; |
| /* things got complicated... */ |
| offset = inode->i_size & (PAGE_CACHE_SIZE-1); |
| /* OK, are we completely out? */ |
| if (page->index >= end_index+1 || !offset) |
| return 0; /* truncated - don't care */ |
| do_it: |
| page_cache_get(page); |
| err = smb_writepage_sync(inode, page, 0, offset); |
| SetPageUptodate(page); |
| unlock_page(page); |
| page_cache_release(page); |
| return err; |
| } |
| |
| static int |
| smb_updatepage(struct file *file, struct page *page, unsigned long offset, |
| unsigned int count) |
| { |
| struct dentry *dentry = file->f_dentry; |
| |
| DEBUG1("(%s/%s %d@%ld)\n", DENTRY_PATH(dentry), |
| count, (page->index << PAGE_CACHE_SHIFT)+offset); |
| |
| return smb_writepage_sync(dentry->d_inode, page, offset, count); |
| } |
| |
| static ssize_t |
| smb_file_read(struct file * file, char __user * buf, size_t count, loff_t *ppos) |
| { |
| struct dentry * dentry = file->f_dentry; |
| ssize_t status; |
| |
| VERBOSE("file %s/%s, count=%lu@%lu\n", DENTRY_PATH(dentry), |
| (unsigned long) count, (unsigned long) *ppos); |
| |
| status = smb_revalidate_inode(dentry); |
| if (status) { |
| PARANOIA("%s/%s validation failed, error=%Zd\n", |
| DENTRY_PATH(dentry), status); |
| goto out; |
| } |
| |
| VERBOSE("before read, size=%ld, flags=%x, atime=%ld\n", |
| (long)dentry->d_inode->i_size, |
| dentry->d_inode->i_flags, dentry->d_inode->i_atime); |
| |
| status = generic_file_read(file, buf, count, ppos); |
| out: |
| return status; |
| } |
| |
| static int |
| smb_file_mmap(struct file * file, struct vm_area_struct * vma) |
| { |
| struct dentry * dentry = file->f_dentry; |
| int status; |
| |
| VERBOSE("file %s/%s, address %lu - %lu\n", |
| DENTRY_PATH(dentry), vma->vm_start, vma->vm_end); |
| |
| status = smb_revalidate_inode(dentry); |
| if (status) { |
| PARANOIA("%s/%s validation failed, error=%d\n", |
| DENTRY_PATH(dentry), status); |
| goto out; |
| } |
| status = generic_file_mmap(file, vma); |
| out: |
| return status; |
| } |
| |
| static ssize_t |
| smb_file_sendfile(struct file *file, loff_t *ppos, |
| size_t count, read_actor_t actor, void *target) |
| { |
| struct dentry *dentry = file->f_dentry; |
| ssize_t status; |
| |
| VERBOSE("file %s/%s, pos=%Ld, count=%d\n", |
| DENTRY_PATH(dentry), *ppos, count); |
| |
| status = smb_revalidate_inode(dentry); |
| if (status) { |
| PARANOIA("%s/%s validation failed, error=%Zd\n", |
| DENTRY_PATH(dentry), status); |
| goto out; |
| } |
| status = generic_file_sendfile(file, ppos, count, actor, target); |
| out: |
| return status; |
| } |
| |
| /* |
| * This does the "real" work of the write. The generic routine has |
| * allocated the page, locked it, done all the page alignment stuff |
| * calculations etc. Now we should just copy the data from user |
| * space and write it back to the real medium.. |
| * |
| * If the writer ends up delaying the write, the writer needs to |
| * increment the page use counts until he is done with the page. |
| */ |
| static int smb_prepare_write(struct file *file, struct page *page, |
| unsigned offset, unsigned to) |
| { |
| return 0; |
| } |
| |
| static int smb_commit_write(struct file *file, struct page *page, |
| unsigned offset, unsigned to) |
| { |
| int status; |
| |
| status = -EFAULT; |
| lock_kernel(); |
| status = smb_updatepage(file, page, offset, to-offset); |
| unlock_kernel(); |
| return status; |
| } |
| |
| struct address_space_operations smb_file_aops = { |
| .readpage = smb_readpage, |
| .writepage = smb_writepage, |
| .prepare_write = smb_prepare_write, |
| .commit_write = smb_commit_write |
| }; |
| |
| /* |
| * Write to a file (through the page cache). |
| */ |
| static ssize_t |
| smb_file_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos) |
| { |
| struct dentry * dentry = file->f_dentry; |
| ssize_t result; |
| |
| VERBOSE("file %s/%s, count=%lu@%lu\n", |
| DENTRY_PATH(dentry), |
| (unsigned long) count, (unsigned long) *ppos); |
| |
| result = smb_revalidate_inode(dentry); |
| if (result) { |
| PARANOIA("%s/%s validation failed, error=%Zd\n", |
| DENTRY_PATH(dentry), result); |
| goto out; |
| } |
| |
| result = smb_open(dentry, SMB_O_WRONLY); |
| if (result) |
| goto out; |
| |
| if (count > 0) { |
| result = generic_file_write(file, buf, count, ppos); |
| VERBOSE("pos=%ld, size=%ld, mtime=%ld, atime=%ld\n", |
| (long) file->f_pos, (long) dentry->d_inode->i_size, |
| dentry->d_inode->i_mtime, dentry->d_inode->i_atime); |
| } |
| out: |
| return result; |
| } |
| |
| static int |
| smb_file_open(struct inode *inode, struct file * file) |
| { |
| int result; |
| struct dentry *dentry = file->f_dentry; |
| int smb_mode = (file->f_mode & O_ACCMODE) - 1; |
| |
| lock_kernel(); |
| result = smb_open(dentry, smb_mode); |
| if (result) |
| goto out; |
| SMB_I(inode)->openers++; |
| out: |
| unlock_kernel(); |
| return result; |
| } |
| |
| static int |
| smb_file_release(struct inode *inode, struct file * file) |
| { |
| lock_kernel(); |
| if (!--SMB_I(inode)->openers) { |
| /* We must flush any dirty pages now as we won't be able to |
| write anything after close. mmap can trigger this. |
| "openers" should perhaps include mmap'ers ... */ |
| filemap_write_and_wait(inode->i_mapping); |
| smb_close(inode); |
| } |
| unlock_kernel(); |
| return 0; |
| } |
| |
| /* |
| * Check whether the required access is compatible with |
| * an inode's permission. SMB doesn't recognize superuser |
| * privileges, so we need our own check for this. |
| */ |
| static int |
| smb_file_permission(struct inode *inode, int mask, struct nameidata *nd) |
| { |
| int mode = inode->i_mode; |
| int error = 0; |
| |
| VERBOSE("mode=%x, mask=%x\n", mode, mask); |
| |
| /* Look at user permissions */ |
| mode >>= 6; |
| if ((mode & 7 & mask) != mask) |
| error = -EACCES; |
| return error; |
| } |
| |
| struct file_operations smb_file_operations = |
| { |
| .llseek = remote_llseek, |
| .read = smb_file_read, |
| .write = smb_file_write, |
| .ioctl = smb_ioctl, |
| .mmap = smb_file_mmap, |
| .open = smb_file_open, |
| .release = smb_file_release, |
| .fsync = smb_fsync, |
| .sendfile = smb_file_sendfile, |
| }; |
| |
| struct inode_operations smb_file_inode_operations = |
| { |
| .permission = smb_file_permission, |
| .getattr = smb_getattr, |
| .setattr = smb_notify_change, |
| }; |