switch generic_write_checks() to iocb and iter

[linux-2.6-block.git] / mm / filemap.c

diff --git a/mm/filemap.c b/mm/filemap.c
index dfc573c6ec25d3530570752cc1062e42fd345752..243997a26e7cebbc52bbc4347555bc50f374a193 100644 (file)
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -2260,36 +2260,38 @@ 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)
+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;
 
        /* FIXME: this is for backwards compatibility with 2.4 */
        if (file->f_flags & O_APPEND)
-               *pos = i_size_read(inode);
+               iocb->ki_pos = i_size_read(inode);
+
+       pos = iocb->ki_pos;
 
        if (limit != RLIM_INFINITY) {
-               if (*pos >= limit) {
+               if (iocb->ki_pos >= limit) {
                        send_sig(SIGXFSZ, current, 0);
                        return -EFBIG;
                }
-               if (*count > limit - (typeof(limit))*pos)
-                       *count = limit - (typeof(limit))*pos;
+               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);
        }
 
        /*
@@ -2299,16 +2301,11 @@ inline int generic_write_checks(struct file *file, loff_t *pos, size_t *count)
         * exceeded without writing data we send a signal and return EFBIG.
         * Linus frestrict idea will clean these up nicely..
         */
-       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;
-       return 0;
+       iov_iter_truncate(from, inode->i_sb->s_maxbytes - pos);
+       return iov_iter_count(from);
 }
 EXPORT_SYMBOL(generic_write_checks);
 
@@ -2618,14 +2615,11 @@ ssize_t generic_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
        struct file *file = iocb->ki_filp;
        struct inode *inode = file->f_mapping->host;
        ssize_t ret;
-       size_t count = iov_iter_count(from);
 
        mutex_lock(&inode->i_mutex);
-       ret = generic_write_checks(file, &iocb->ki_pos, &count);
-       if (!ret && count) {
-               iov_iter_truncate(from, count);
+       ret = generic_write_checks(iocb, from);
+       if (ret > 0)
                ret = __generic_file_write_iter(iocb, from);
-       }
        mutex_unlock(&inode->i_mutex);
 
        if (ret > 0) {