drm/i915/dp: there is no audio on port A
[linux-2.6-block.git] / mm / filemap.c
index 12548d03c11de9e3f114897ddc031dbb525f550c..6bf5e42d560a46eea8e4916bd017d855033b8d65 100644 (file)
@@ -1693,7 +1693,7 @@ generic_file_read_iter(struct kiocb *iocb, struct iov_iter *iter)
        loff_t *ppos = &iocb->ki_pos;
        loff_t pos = *ppos;
 
-       if (io_is_direct(file)) {
+       if (iocb->ki_flags & IOCB_DIRECT) {
                struct address_space *mapping = file->f_mapping;
                struct inode *inode = mapping->host;
                size_t count = iov_iter_count(iter);
@@ -1706,7 +1706,7 @@ generic_file_read_iter(struct kiocb *iocb, struct iov_iter *iter)
                                        pos + count - 1);
                if (!retval) {
                        struct iov_iter data = *iter;
-                       retval = mapping->a_ops->direct_IO(READ, iocb, &data, pos);
+                       retval = mapping->a_ops->direct_IO(iocb, &data, pos);
                }
 
                if (retval > 0) {
@@ -2259,41 +2259,38 @@ EXPORT_SYMBOL(read_cache_page_gfp);
  * Returns appropriate error code that caller should return or
  * zero in case that write should be allowed.
  */
-inline int generic_write_checks(struct file *file, loff_t *pos, size_t *count, int isblk)
+inline ssize_t generic_write_checks(struct kiocb *iocb, struct iov_iter *from)
 {
+       struct file *file = iocb->ki_filp;
        struct inode *inode = file->f_mapping->host;
        unsigned long limit = rlimit(RLIMIT_FSIZE);
+       loff_t pos;
 
-        if (unlikely(*pos < 0))
-                return -EINVAL;
+       if (!iov_iter_count(from))
+               return 0;
 
-       if (!isblk) {
-               /* FIXME: this is for backwards compatibility with 2.4 */
-               if (file->f_flags & O_APPEND)
-                        *pos = i_size_read(inode);
+       /* FIXME: this is for backwards compatibility with 2.4 */
+       if (iocb->ki_flags & IOCB_APPEND)
+               iocb->ki_pos = i_size_read(inode);
 
-               if (limit != RLIM_INFINITY) {
-                       if (*pos >= limit) {
-                               send_sig(SIGXFSZ, current, 0);
-                               return -EFBIG;
-                       }
-                       if (*count > limit - (typeof(limit))*pos) {
-                               *count = limit - (typeof(limit))*pos;
-                       }
+       pos = iocb->ki_pos;
+
+       if (limit != RLIM_INFINITY) {
+               if (iocb->ki_pos >= limit) {
+                       send_sig(SIGXFSZ, current, 0);
+                       return -EFBIG;
                }
+               iov_iter_truncate(from, limit - (unsigned long)pos);
        }
 
        /*
         * LFS rule
         */
-       if (unlikely(*pos + *count > MAX_NON_LFS &&
+       if (unlikely(pos + iov_iter_count(from) > MAX_NON_LFS &&
                                !(file->f_flags & O_LARGEFILE))) {
-               if (*pos >= MAX_NON_LFS) {
+               if (pos >= MAX_NON_LFS)
                        return -EFBIG;
-               }
-               if (*count > MAX_NON_LFS - (unsigned long)*pos) {
-                       *count = MAX_NON_LFS - (unsigned long)*pos;
-               }
+               iov_iter_truncate(from, MAX_NON_LFS - (unsigned long)pos);
        }
 
        /*
@@ -2303,34 +2300,11 @@ inline int generic_write_checks(struct file *file, loff_t *pos, size_t *count, i
         * exceeded without writing data we send a signal and return EFBIG.
         * Linus frestrict idea will clean these up nicely..
         */
-       if (likely(!isblk)) {
-               if (unlikely(*pos >= inode->i_sb->s_maxbytes)) {
-                       if (*count || *pos > inode->i_sb->s_maxbytes) {
-                               return -EFBIG;
-                       }
-                       /* zero-length writes at ->s_maxbytes are OK */
-               }
+       if (unlikely(pos >= inode->i_sb->s_maxbytes))
+               return -EFBIG;
 
-               if (unlikely(*pos + *count > inode->i_sb->s_maxbytes))
-                       *count = inode->i_sb->s_maxbytes - *pos;
-       } else {
-#ifdef CONFIG_BLOCK
-               loff_t isize;
-               if (bdev_read_only(I_BDEV(inode)))
-                       return -EPERM;
-               isize = i_size_read(inode);
-               if (*pos >= isize) {
-                       if (*count || *pos > isize)
-                               return -ENOSPC;
-               }
-
-               if (*pos + *count > isize)
-                       *count = isize - *pos;
-#else
-               return -EPERM;
-#endif
-       }
-       return 0;
+       iov_iter_truncate(from, inode->i_sb->s_maxbytes - pos);
+       return iov_iter_count(from);
 }
 EXPORT_SYMBOL(generic_write_checks);
 
@@ -2394,7 +2368,7 @@ generic_file_direct_write(struct kiocb *iocb, struct iov_iter *from, loff_t pos)
        }
 
        data = *from;
-       written = mapping->a_ops->direct_IO(WRITE, iocb, &data, pos);
+       written = mapping->a_ops->direct_IO(iocb, &data, pos);
 
        /*
         * Finally, try again to invalidate clean pages which might have been
@@ -2556,23 +2530,12 @@ ssize_t __generic_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
        struct file *file = iocb->ki_filp;
        struct address_space * mapping = file->f_mapping;
        struct inode    *inode = mapping->host;
-       loff_t          pos = iocb->ki_pos;
        ssize_t         written = 0;
        ssize_t         err;
        ssize_t         status;
-       size_t          count = iov_iter_count(from);
 
        /* We can write back this queue in page reclaim */
        current->backing_dev_info = inode_to_bdi(inode);
-       err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
-       if (err)
-               goto out;
-
-       if (count == 0)
-               goto out;
-
-       iov_iter_truncate(from, count);
-
        err = file_remove_suid(file);
        if (err)
                goto out;
@@ -2581,10 +2544,10 @@ ssize_t __generic_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
        if (err)
                goto out;
 
-       if (io_is_direct(file)) {
-               loff_t endbyte;
+       if (iocb->ki_flags & IOCB_DIRECT) {
+               loff_t pos, endbyte;
 
-               written = generic_file_direct_write(iocb, from, pos);
+               written = generic_file_direct_write(iocb, from, iocb->ki_pos);
                /*
                 * If the write stopped short of completing, fall back to
                 * buffered writes.  Some filesystems do this for writes to
@@ -2592,13 +2555,10 @@ ssize_t __generic_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
                 * not succeed (even if it did, DAX does not handle dirty
                 * page-cache pages correctly).
                 */
-               if (written < 0 || written == count || IS_DAX(inode))
+               if (written < 0 || !iov_iter_count(from) || IS_DAX(inode))
                        goto out;
 
-               pos += written;
-               count -= written;
-
-               status = generic_perform_write(file, from, pos);
+               status = generic_perform_write(file, from, pos = iocb->ki_pos);
                /*
                 * If generic_perform_write() returned a synchronous error
                 * then we want to return the number of bytes which were
@@ -2610,15 +2570,15 @@ ssize_t __generic_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
                        err = status;
                        goto out;
                }
-               iocb->ki_pos = pos + status;
                /*
                 * We need to ensure that the page cache pages are written to
                 * disk and invalidated to preserve the expected O_DIRECT
                 * semantics.
                 */
                endbyte = pos + status - 1;
-               err = filemap_write_and_wait_range(file->f_mapping, pos, endbyte);
+               err = filemap_write_and_wait_range(mapping, pos, endbyte);
                if (err == 0) {
+                       iocb->ki_pos = endbyte + 1;
                        written += status;
                        invalidate_mapping_pages(mapping,
                                                 pos >> PAGE_CACHE_SHIFT,
@@ -2630,9 +2590,9 @@ ssize_t __generic_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
                         */
                }
        } else {
-               written = generic_perform_write(file, from, pos);
-               if (likely(written >= 0))
-                       iocb->ki_pos = pos + written;
+               written = generic_perform_write(file, from, iocb->ki_pos);
+               if (likely(written > 0))
+                       iocb->ki_pos += written;
        }
 out:
        current->backing_dev_info = NULL;
@@ -2656,7 +2616,9 @@ ssize_t generic_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
        ssize_t ret;
 
        mutex_lock(&inode->i_mutex);
-       ret = __generic_file_write_iter(iocb, from);
+       ret = generic_write_checks(iocb, from);
+       if (ret > 0)
+               ret = __generic_file_write_iter(iocb, from);
        mutex_unlock(&inode->i_mutex);
 
        if (ret > 0) {