/* * 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 <linux/aio.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_path.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; BUG_ON(!mapping); inode = mapping->host; BUG_ON(!inode); 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_path.dentry; DEBUG1("(%s/%s %d@%lld)\n", DENTRY_PATH(dentry), count, ((unsigned long long)page->index << PAGE_CACHE_SHIFT) + offset); return smb_writepage_sync(dentry->d_inode, page, offset, count); } static ssize_t smb_file_aio_read(struct kiocb *iocb, const struct iovec *iov, unsigned long nr_segs, loff_t pos) { struct file * file = iocb->ki_filp; struct dentry * dentry = file->f_path.dentry; ssize_t status; VERBOSE("file %s/%s, count=%lu@%lu\n", DENTRY_PATH(dentry), (unsigned long) iocb->ki_left, (unsigned long) pos); 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.tv_sec); status = generic_file_aio_read(iocb, iov, nr_segs, pos); out: return status; } static int smb_file_mmap(struct file * file, struct vm_area_struct * vma) { struct dentry * dentry = file->f_path.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_splice_read(struct file *file, loff_t *ppos, struct pipe_inode_info *pipe, size_t count, unsigned int flags) { struct dentry *dentry = file->f_path.dentry; ssize_t status; VERBOSE("file %s/%s, pos=%Ld, count=%lu\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_splice_read(file, ppos, pipe, count, flags); 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_write_begin(struct file *file, struct address_space *mapping, loff_t pos, unsigned len, unsigned flags, struct page **pagep, void **fsdata) { pgoff_t index = pos >> PAGE_CACHE_SHIFT; *pagep = __grab_cache_page(mapping, index); if (!*pagep) return -ENOMEM; return 0; } static int smb_write_end(struct file *file, struct address_space *mapping, loff_t pos, unsigned len, unsigned copied, struct page *page, void *fsdata) { int status; unsigned offset = pos & (PAGE_CACHE_SIZE - 1); lock_kernel(); status = smb_updatepage(file, page, offset, copied); unlock_kernel(); if (!status) { if (!PageUptodate(page) && copied == PAGE_CACHE_SIZE) SetPageUptodate(page); status = copied; } unlock_page(page); page_cache_release(page); return status; } const struct address_space_operations smb_file_aops = { .readpage = smb_readpage, .writepage = smb_writepage, .write_begin = smb_write_begin, .write_end = smb_write_end, }; /* * Write to a file (through the page cache). */ static ssize_t smb_file_aio_write(struct kiocb *iocb, const struct iovec *iov, unsigned long nr_segs, loff_t pos) { struct file * file = iocb->ki_filp; struct dentry * dentry = file->f_path.dentry; ssize_t result; VERBOSE("file %s/%s, count=%lu@%lu\n", DENTRY_PATH(dentry), (unsigned long) iocb->ki_left, (unsigned long) pos); 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 (iocb->ki_left > 0) { result = generic_file_aio_write(iocb, iov, nr_segs, pos); 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.tv_sec, dentry->d_inode->i_atime.tv_sec); } out: return result; } static int smb_file_open(struct inode *inode, struct file * file) { int result; struct dentry *dentry = file->f_path.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; } const struct file_operations smb_file_operations = { .llseek = remote_llseek, .read = do_sync_read, .aio_read = smb_file_aio_read, .write = do_sync_write, .aio_write = smb_file_aio_write, .ioctl = smb_ioctl, .mmap = smb_file_mmap, .open = smb_file_open, .release = smb_file_release, .fsync = smb_fsync, .splice_read = smb_file_splice_read, }; const struct inode_operations smb_file_inode_operations = { .permission = smb_file_permission, .getattr = smb_getattr, .setattr = smb_notify_change, };