1 files changed, 423 insertions, 0 deletions

diff --git a/fs/smbfs/file.c b/fs/smbfs/file.c
new file mode 100644
index 000000000000..b4fcfa8b55a1
--- /dev/null
+++ b/fs/smbfs/file.c
@@ -0,0 +1,423 @@
+/*
+ *  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_fdatawrite(inode->i_mapping);
+                filemap_fdatawait(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,
+};