+
+ mutex_unlock(&sdp->sd_quota_mutex);
+}
+
+static void gfs2_quota_in(struct gfs2_quota_host *qu, const void *buf)
+{
+ const struct gfs2_quota *str = buf;
+
+ qu->qu_limit = be64_to_cpu(str->qu_limit);
+ qu->qu_warn = be64_to_cpu(str->qu_warn);
+ qu->qu_value = be64_to_cpu(str->qu_value);
+ qu->qu_ll_next = be32_to_cpu(str->qu_ll_next);
+}
+
+static void gfs2_quota_out(const struct gfs2_quota_host *qu, void *buf)
+{
+ struct gfs2_quota *str = buf;
+
+ str->qu_limit = cpu_to_be64(qu->qu_limit);
+ str->qu_warn = cpu_to_be64(qu->qu_warn);
+ str->qu_value = cpu_to_be64(qu->qu_value);
+ str->qu_ll_next = cpu_to_be32(qu->qu_ll_next);
+ memset(&str->qu_reserved, 0, sizeof(str->qu_reserved));
+}
+
+/**
+ * gfs2_adjust_quota
+ *
+ * This function was mostly borrowed from gfs2_block_truncate_page which was
+ * in turn mostly borrowed from ext3
+ */
+static int gfs2_adjust_quota(struct gfs2_inode *ip, loff_t loc,
+ s64 change, struct gfs2_quota_data *qd)
+{
+ struct inode *inode = &ip->i_inode;
+ struct address_space *mapping = inode->i_mapping;
+ unsigned long index = loc >> PAGE_CACHE_SHIFT;
+ unsigned offset = loc & (PAGE_CACHE_SIZE - 1);
+ unsigned blocksize, iblock, pos;
+ struct buffer_head *bh;
+ struct page *page;
+ void *kaddr;
+ char *ptr;
+ struct gfs2_quota_host qp;
+ s64 value;
+ int err = -EIO;
+
+ if (gfs2_is_stuffed(ip)) {
+ struct gfs2_alloc *al = NULL;
+ al = gfs2_alloc_get(ip);
+ /* just request 1 blk */
+ al->al_requested = 1;
+ gfs2_inplace_reserve(ip);
+ gfs2_unstuff_dinode(ip, NULL);
+ gfs2_inplace_release(ip);
+ gfs2_alloc_put(ip);
+ }
+ page = grab_cache_page(mapping, index);
+ if (!page)
+ return -ENOMEM;
+
+ blocksize = inode->i_sb->s_blocksize;
+ iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
+
+ if (!page_has_buffers(page))
+ create_empty_buffers(page, blocksize, 0);
+
+ bh = page_buffers(page);
+ pos = blocksize;
+ while (offset >= pos) {
+ bh = bh->b_this_page;
+ iblock++;
+ pos += blocksize;
+ }
+
+ if (!buffer_mapped(bh)) {
+ gfs2_block_map(inode, iblock, bh, 1);
+ if (!buffer_mapped(bh))
+ goto unlock;
+ }
+
+ if (PageUptodate(page))
+ set_buffer_uptodate(bh);
+
+ if (!buffer_uptodate(bh)) {
+ ll_rw_block(READ_META, 1, &bh);
+ wait_on_buffer(bh);
+ if (!buffer_uptodate(bh))
+ goto unlock;
+ }
+
+ gfs2_trans_add_bh(ip->i_gl, bh, 0);
+
+ kaddr = kmap_atomic(page, KM_USER0);
+ ptr = kaddr + offset;
+ gfs2_quota_in(&qp, ptr);
+ qp.qu_value += change;
+ value = qp.qu_value;
+ gfs2_quota_out(&qp, ptr);
+ flush_dcache_page(page);
+ kunmap_atomic(kaddr, KM_USER0);
+ err = 0;
+ qd->qd_qb.qb_magic = cpu_to_be32(GFS2_MAGIC);
+ qd->qd_qb.qb_value = cpu_to_be64(value);
+ ((struct gfs2_quota_lvb*)(qd->qd_gl->gl_lvb))->qb_magic = cpu_to_be32(GFS2_MAGIC);
+ ((struct gfs2_quota_lvb*)(qd->qd_gl->gl_lvb))->qb_value = cpu_to_be64(value);
+unlock:
+ unlock_page(page);
+ page_cache_release(page);
+ return err;