X-Git-Url: https://git.stricted.de/?a=blobdiff_plain;f=fs%2Fext4%2Ffile.c;h=ed2badabebf0074fc95f1fcae76600c75381f91f;hb=bdecc6d1840bca102c4eb6113c6218e1ae8913f5;hp=b1b4d51b5d86b4e54c179ddce5f5b574238b3629;hpb=e6395b68ad09a835f058da31bad0fe23d3882659;p=GitHub%2Fmt8127%2Fandroid_kernel_alcatel_ttab.git

diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index b1b4d51b5d86..ed2badabebf0 100644
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -82,7 +82,7 @@ ext4_unaligned_aio(struct inode *inode, const struct iovec *iov,
 	size_t count = iov_length(iov, nr_segs);
 	loff_t final_size = pos + count;
 
-	if (pos >= inode->i_size)
+	if (pos >= i_size_read(inode))
 		return 0;
 
 	if ((pos & blockmask) || (final_size & blockmask))
@@ -100,7 +100,7 @@ ext4_file_dio_write(struct kiocb *iocb, const struct iovec *iov,
 	struct blk_plug plug;
 	int unaligned_aio = 0;
 	ssize_t ret;
-	int overwrite = 0;
+	int *overwrite = iocb->private;
 	size_t length = iov_length(iov, nr_segs);
 
 	if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS) &&
@@ -118,8 +118,6 @@ ext4_file_dio_write(struct kiocb *iocb, const struct iovec *iov,
 	mutex_lock(&inode->i_mutex);
 	blk_start_plug(&plug);
 
-	iocb->private = &overwrite;
-
 	/* check whether we do a DIO overwrite or not */
 	if (ext4_should_dioread_nolock(inode) && !unaligned_aio &&
 	    !file->f_mapping->nrpages && pos + length <= i_size_read(inode)) {
@@ -143,7 +141,7 @@ ext4_file_dio_write(struct kiocb *iocb, const struct iovec *iov,
 		 * So we should check these two conditions.
 		 */
 		if (err == len && (map.m_flags & EXT4_MAP_MAPPED))
-			overwrite = 1;
+			*overwrite = 1;
 	}
 
 	ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos);
@@ -170,6 +168,7 @@ ext4_file_write(struct kiocb *iocb, const struct iovec *iov,
 {
 	struct inode *inode = file_inode(iocb->ki_filp);
 	ssize_t ret;
+	int overwrite = 0;
 
 	/*
 	 * If we have encountered a bitmap-format file, the size limit
@@ -190,6 +189,7 @@ ext4_file_write(struct kiocb *iocb, const struct iovec *iov,
 		}
 	}
 
+	iocb->private = &overwrite;
 	if (unlikely(iocb->ki_filp->f_flags & O_DIRECT))
 		ret = ext4_file_dio_write(iocb, iov, nr_segs, pos);
 	else
@@ -312,7 +312,7 @@ static int ext4_find_unwritten_pgoff(struct inode *inode,
 	blkbits = inode->i_sb->s_blocksize_bits;
 	startoff = *offset;
 	lastoff = startoff;
-	endoff = (map->m_lblk + map->m_len) << blkbits;
+	endoff = (loff_t)(map->m_lblk + map->m_len) << blkbits;
 
 	index = startoff >> PAGE_CACHE_SHIFT;
 	end = endoff >> PAGE_CACHE_SHIFT;
@@ -325,47 +325,27 @@ static int ext4_find_unwritten_pgoff(struct inode *inode,
 		num = min_t(pgoff_t, end - index, PAGEVEC_SIZE);
 		nr_pages = pagevec_lookup(&pvec, inode->i_mapping, index,
 					  (pgoff_t)num);
-		if (nr_pages == 0) {
-			if (whence == SEEK_DATA)
-				break;
-
-			BUG_ON(whence != SEEK_HOLE);
-			/*
-			 * If this is the first time to go into the loop and
-			 * offset is not beyond the end offset, it will be a
-			 * hole at this offset
-			 */
-			if (lastoff == startoff || lastoff < endoff)
-				found = 1;
-			break;
-		}
-
-		/*
-		 * If this is the first time to go into the loop and
-		 * offset is smaller than the first page offset, it will be a
-		 * hole at this offset.
-		 */
-		if (lastoff == startoff && whence == SEEK_HOLE &&
-		    lastoff < page_offset(pvec.pages[0])) {
-			found = 1;
+		if (nr_pages == 0)
 			break;
-		}
 
 		for (i = 0; i < nr_pages; i++) {
 			struct page *page = pvec.pages[i];
 			struct buffer_head *bh, *head;
 
 			/*
-			 * If the current offset is not beyond the end of given
-			 * range, it will be a hole.
+			 * If current offset is smaller than the page offset,
+			 * there is a hole at this offset.
 			 */
-			if (lastoff < endoff && whence == SEEK_HOLE &&
-			    page->index > end) {
+			if (whence == SEEK_HOLE && lastoff < endoff &&
+			    lastoff < page_offset(pvec.pages[i])) {
 				found = 1;
 				*offset = lastoff;
 				goto out;
 			}
 
+			if (page->index > end)
+				goto out;
+
 			lock_page(page);
 
 			if (unlikely(page->mapping != inode->i_mapping)) {
@@ -382,6 +362,8 @@ static int ext4_find_unwritten_pgoff(struct inode *inode,
 				lastoff = page_offset(page);
 				bh = head = page_buffers(page);
 				do {
+					if (lastoff + bh->b_size <= startoff)
+						goto next;
 					if (buffer_uptodate(bh) ||
 					    buffer_unwritten(bh)) {
 						if (whence == SEEK_DATA)
@@ -396,6 +378,7 @@ static int ext4_find_unwritten_pgoff(struct inode *inode,
 						unlock_page(page);
 						goto out;
 					}
+next:
 					lastoff += bh->b_size;
 					bh = bh->b_this_page;
 				} while (bh != head);
@@ -405,20 +388,18 @@ static int ext4_find_unwritten_pgoff(struct inode *inode,
 			unlock_page(page);
 		}
 
-		/*
-		 * The no. of pages is less than our desired, that would be a
-		 * hole in there.
-		 */
-		if (nr_pages < num && whence == SEEK_HOLE) {
-			found = 1;
-			*offset = lastoff;
+		/* The no. of pages is less than our desired, we are done. */
+		if (nr_pages < num)
 			break;
-		}
 
 		index = pvec.pages[i - 1]->index + 1;
 		pagevec_release(&pvec);
 	} while (index <= end);
 
+	if (whence == SEEK_HOLE && lastoff < endoff) {
+		found = 1;
+		*offset = lastoff;
+	}
 out:
 	pagevec_release(&pvec);
 	return found;
@@ -440,7 +421,7 @@ static loff_t ext4_seek_data(struct file *file, loff_t offset, loff_t maxsize)
 	mutex_lock(&inode->i_mutex);
 
 	isize = i_size_read(inode);
-	if (offset >= isize) {
+	if (offset < 0 || offset >= isize) {
 		mutex_unlock(&inode->i_mutex);
 		return -ENXIO;
 	}
@@ -457,7 +438,7 @@ static loff_t ext4_seek_data(struct file *file, loff_t offset, loff_t maxsize)
 		ret = ext4_map_blocks(NULL, inode, &map, 0);
 		if (ret > 0 && !(map.m_flags & EXT4_MAP_UNWRITTEN)) {
 			if (last != start)
-				dataoff = last << blkbits;
+				dataoff = (loff_t)last << blkbits;
 			break;
 		}
 
@@ -468,7 +449,7 @@ static loff_t ext4_seek_data(struct file *file, loff_t offset, loff_t maxsize)
 		ext4_es_find_delayed_extent_range(inode, last, last, &es);
 		if (es.es_len != 0 && in_range(last, es.es_lblk, es.es_len)) {
 			if (last != start)
-				dataoff = last << blkbits;
+				dataoff = (loff_t)last << blkbits;
 			break;
 		}
 
@@ -486,7 +467,7 @@ static loff_t ext4_seek_data(struct file *file, loff_t offset, loff_t maxsize)
 		}
 
 		last++;
-		dataoff = last << blkbits;
+		dataoff = (loff_t)last << blkbits;
 	} while (last <= end);
 
 	mutex_unlock(&inode->i_mutex);
@@ -523,7 +504,7 @@ static loff_t ext4_seek_hole(struct file *file, loff_t offset, loff_t maxsize)
 	mutex_lock(&inode->i_mutex);
 
 	isize = i_size_read(inode);
-	if (offset >= isize) {
+	if (offset < 0 || offset >= isize) {
 		mutex_unlock(&inode->i_mutex);
 		return -ENXIO;
 	}
@@ -540,7 +521,7 @@ static loff_t ext4_seek_hole(struct file *file, loff_t offset, loff_t maxsize)
 		ret = ext4_map_blocks(NULL, inode, &map, 0);
 		if (ret > 0 && !(map.m_flags & EXT4_MAP_UNWRITTEN)) {
 			last += ret;
-			holeoff = last << blkbits;
+			holeoff = (loff_t)last << blkbits;
 			continue;
 		}
 
@@ -551,7 +532,7 @@ static loff_t ext4_seek_hole(struct file *file, loff_t offset, loff_t maxsize)
 		ext4_es_find_delayed_extent_range(inode, last, last, &es);
 		if (es.es_len != 0 && in_range(last, es.es_lblk, es.es_len)) {
 			last = es.es_lblk + es.es_len;
-			holeoff = last << blkbits;
+			holeoff = (loff_t)last << blkbits;
 			continue;
 		}
 
@@ -566,7 +547,7 @@ static loff_t ext4_seek_hole(struct file *file, loff_t offset, loff_t maxsize)
 							      &map, &holeoff);
 			if (!unwritten) {
 				last += ret;
-				holeoff = last << blkbits;
+				holeoff = (loff_t)last << blkbits;
 				continue;
 			}
 		}