From d0b2f91bede3bd5e3d24dd6803e56eee959c1797 Mon Sep 17 00:00:00 2001
From: André Fabian Silva Delgado <emulatorman@parabola.nu>
Date: Thu, 20 Oct 2016 00:10:27 -0300
Subject: Linux-libre 4.8.2-gnu

---
 fs/f2fs/gc.c | 64 +++++++++++++++++++++++++++++++++++++++++++++++++-----------
 1 file changed, 53 insertions(+), 11 deletions(-)

(limited to 'fs/f2fs/gc.c')

diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
index 38d56f678..8f7fa326c 100644
--- a/fs/f2fs/gc.c
+++ b/fs/f2fs/gc.c
@@ -538,7 +538,8 @@ static void move_encrypted_block(struct inode *inode, block_t bidx)
 	struct f2fs_io_info fio = {
 		.sbi = F2FS_I_SB(inode),
 		.type = DATA,
-		.rw = READ_SYNC,
+		.op = REQ_OP_READ,
+		.op_flags = READ_SYNC,
 		.encrypted_page = NULL,
 	};
 	struct dnode_of_data dn;
@@ -593,11 +594,11 @@ static void move_encrypted_block(struct inode *inode, block_t bidx)
 	/* write page */
 	lock_page(fio.encrypted_page);
 
-	if (unlikely(!PageUptodate(fio.encrypted_page))) {
+	if (unlikely(fio.encrypted_page->mapping != META_MAPPING(fio.sbi))) {
 		err = -EIO;
 		goto put_page_out;
 	}
-	if (unlikely(fio.encrypted_page->mapping != META_MAPPING(fio.sbi))) {
+	if (unlikely(!PageUptodate(fio.encrypted_page))) {
 		err = -EIO;
 		goto put_page_out;
 	}
@@ -612,14 +613,15 @@ static void move_encrypted_block(struct inode *inode, block_t bidx)
 	/* allocate block address */
 	f2fs_wait_on_page_writeback(dn.node_page, NODE, true);
 
-	fio.rw = WRITE_SYNC;
+	fio.op = REQ_OP_WRITE;
+	fio.op_flags = WRITE_SYNC;
 	fio.new_blkaddr = newaddr;
 	f2fs_submit_page_mbio(&fio);
 
 	f2fs_update_data_blkaddr(&dn, newaddr);
-	set_inode_flag(F2FS_I(inode), FI_APPEND_WRITE);
+	set_inode_flag(inode, FI_APPEND_WRITE);
 	if (page->index == 0)
-		set_inode_flag(F2FS_I(inode), FI_FIRST_BLOCK_WRITTEN);
+		set_inode_flag(inode, FI_FIRST_BLOCK_WRITTEN);
 put_page_out:
 	f2fs_put_page(fio.encrypted_page, 1);
 recover_block:
@@ -649,16 +651,28 @@ static void move_data_page(struct inode *inode, block_t bidx, int gc_type)
 		struct f2fs_io_info fio = {
 			.sbi = F2FS_I_SB(inode),
 			.type = DATA,
-			.rw = WRITE_SYNC,
+			.op = REQ_OP_WRITE,
+			.op_flags = WRITE_SYNC,
 			.page = page,
 			.encrypted_page = NULL,
 		};
+		bool is_dirty = PageDirty(page);
+		int err;
+
+retry:
 		set_page_dirty(page);
 		f2fs_wait_on_page_writeback(page, DATA, true);
 		if (clear_page_dirty_for_io(page))
 			inode_dec_dirty_pages(inode);
+
 		set_cold_data(page);
-		do_write_data_page(&fio);
+
+		err = do_write_data_page(&fio);
+		if (err == -ENOMEM && is_dirty) {
+			congestion_wait(BLK_RW_ASYNC, HZ/50);
+			goto retry;
+		}
+
 		clear_cold_data(page);
 	}
 out:
@@ -730,7 +744,8 @@ next_step:
 
 			start_bidx = start_bidx_of_node(nofs, inode);
 			data_page = get_read_data_page(inode,
-					start_bidx + ofs_in_node, READA, true);
+					start_bidx + ofs_in_node, REQ_RAHEAD,
+					true);
 			if (IS_ERR(data_page)) {
 				iput(inode);
 				continue;
@@ -744,12 +759,32 @@ next_step:
 		/* phase 3 */
 		inode = find_gc_inode(gc_list, dni.ino);
 		if (inode) {
+			struct f2fs_inode_info *fi = F2FS_I(inode);
+			bool locked = false;
+
+			if (S_ISREG(inode->i_mode)) {
+				if (!down_write_trylock(&fi->dio_rwsem[READ]))
+					continue;
+				if (!down_write_trylock(
+						&fi->dio_rwsem[WRITE])) {
+					up_write(&fi->dio_rwsem[READ]);
+					continue;
+				}
+				locked = true;
+			}
+
 			start_bidx = start_bidx_of_node(nofs, inode)
 								+ ofs_in_node;
 			if (f2fs_encrypted_inode(inode) && S_ISREG(inode->i_mode))
 				move_encrypted_block(inode, start_bidx);
 			else
 				move_data_page(inode, start_bidx, gc_type);
+
+			if (locked) {
+				up_write(&fi->dio_rwsem[WRITE]);
+				up_write(&fi->dio_rwsem[READ]);
+			}
+
 			stat_inc_data_blk_count(sbi, 1, gc_type);
 		}
 	}
@@ -798,6 +833,10 @@ static int do_garbage_collect(struct f2fs_sb_info *sbi,
 	blk_start_plug(&plug);
 
 	for (segno = start_segno; segno < end_segno; segno++) {
+
+		if (get_valid_blocks(sbi, segno, 1) == 0)
+			continue;
+
 		/* find segment summary of victim */
 		sum_page = find_get_page(META_MAPPING(sbi),
 					GET_SUM_BLOCK(sbi, segno));
@@ -873,10 +912,13 @@ gc_more:
 		 * enough free sections, we should flush dent/node blocks and do
 		 * garbage collections.
 		 */
-		if (__get_victim(sbi, &segno, gc_type) || prefree_segments(sbi))
+		if (__get_victim(sbi, &segno, gc_type) ||
+						prefree_segments(sbi)) {
 			write_checkpoint(sbi, &cpc);
-		else if (has_not_enough_free_secs(sbi, 0))
+			segno = NULL_SEGNO;
+		} else if (has_not_enough_free_secs(sbi, 0)) {
 			write_checkpoint(sbi, &cpc);
+		}
 	}
 
 	if (segno == NULL_SEGNO && !__get_victim(sbi, &segno, gc_type))
-- 
cgit v1.2.3-54-g00ecf