---

yaml
---
r: 186442
b: refs/heads/master
c: 9421502
h: refs/heads/master
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 5c564c2a04d4bb6ba79eeb83bd06de584479f362
+refs/heads/master: 9421502b4fc894cc477be8fc49776830e37ca157

trunk/fs/logfs/dev_bdev.c

@@ -167,27 +167,91 @@ static void bdev_writeseg(struct super_block *sb, u64 ofs, size_t len)
 	generic_unplug_device(bdev_get_queue(logfs_super(sb)->s_bdev));
 }
 
-static int bdev_erase(struct super_block *sb, loff_t to, size_t len)
+
+static void erase_end_io(struct bio *bio, int err) 
+{ 
+	const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); 
+	struct super_block *sb = bio->bi_private; 
+	struct logfs_super *super = logfs_super(sb); 
+
+	BUG_ON(!uptodate); /* FIXME: Retry io or write elsewhere */ 
+	BUG_ON(err); 
+	BUG_ON(bio->bi_vcnt == 0); 
+	bio_put(bio); 
+	if (atomic_dec_and_test(&super->s_pending_writes))
+		wake_up(&wq); 
+} 
+
+static int do_erase(struct super_block *sb, u64 ofs, pgoff_t index,
+		size_t nr_pages)
+{
+	struct logfs_super *super = logfs_super(sb);
+	struct bio *bio;
+	struct request_queue *q = bdev_get_queue(sb->s_bdev);
+	unsigned int max_pages = queue_max_hw_sectors(q) >> (PAGE_SHIFT - 9);
+	int i;
+
+	bio = bio_alloc(GFP_NOFS, max_pages);
+	BUG_ON(!bio); /* FIXME: handle this */
+
+	for (i = 0; i < nr_pages; i++) {
+		if (i >= max_pages) {
+			/* Block layer cannot split bios :( */
+			bio->bi_vcnt = i;
+			bio->bi_idx = 0;
+			bio->bi_size = i * PAGE_SIZE;
+			bio->bi_bdev = super->s_bdev;
+			bio->bi_sector = ofs >> 9;
+			bio->bi_private = sb;
+			bio->bi_end_io = erase_end_io;
+			atomic_inc(&super->s_pending_writes);
+			submit_bio(WRITE, bio);
+
+			ofs += i * PAGE_SIZE;
+			index += i;
+			nr_pages -= i;
+			i = 0;
+
+			bio = bio_alloc(GFP_NOFS, max_pages);
+			BUG_ON(!bio);
+		}
+		bio->bi_io_vec[i].bv_page = super->s_erase_page;
+		bio->bi_io_vec[i].bv_len = PAGE_SIZE;
+		bio->bi_io_vec[i].bv_offset = 0;
+	}
+	bio->bi_vcnt = nr_pages;
+	bio->bi_idx = 0;
+	bio->bi_size = nr_pages * PAGE_SIZE;
+	bio->bi_bdev = super->s_bdev;
+	bio->bi_sector = ofs >> 9;
+	bio->bi_private = sb;
+	bio->bi_end_io = erase_end_io;
+	atomic_inc(&super->s_pending_writes);
+	submit_bio(WRITE, bio);
+	return 0;
+}
+
+static int bdev_erase(struct super_block *sb, loff_t to, size_t len,
+		int ensure_write)
 {
 	struct logfs_super *super = logfs_super(sb);
-	struct address_space *mapping = super->s_mapping_inode->i_mapping;
-	struct page *page;
-	pgoff_t index = to >> PAGE_SHIFT;
-	int i, nr_pages = len >> PAGE_SHIFT;
 
 	BUG_ON(to & (PAGE_SIZE - 1));
 	BUG_ON(len & (PAGE_SIZE - 1));
 
-	if (logfs_super(sb)->s_flags & LOGFS_SB_FLAG_RO)
+	if (super->s_flags & LOGFS_SB_FLAG_RO)
 		return -EROFS;
 
-	for (i = 0; i < nr_pages; i++) {
-		page = find_get_page(mapping, index + i);
-		if (page) {
-			memset(page_address(page), 0xFF, PAGE_SIZE);
-			page_cache_release(page);
-		}
+	if (ensure_write) {
+		/*
+		 * Object store doesn't care whether erases happen or not.
+		 * But for the journal they are required.  Otherwise a scan
+		 * can find an old commit entry and assume it is the current
+		 * one, travelling back in time.
+		 */
+		do_erase(sb, to, to >> PAGE_SHIFT, len >> PAGE_SHIFT);
 	}
+
 	return 0;
 }
 

trunk/fs/logfs/dev_mtd.c

@@ -83,7 +83,8 @@ static int mtd_erase_mapping(struct super_block *sb, loff_t ofs, size_t len)
 	return 0;
 }
 
-static int mtd_erase(struct super_block *sb, loff_t ofs, size_t len)
+static int mtd_erase(struct super_block *sb, loff_t ofs, size_t len,
+		int ensure_write)
 {
 	struct mtd_info *mtd = logfs_super(sb)->s_mtd;
 	struct erase_info ei;

trunk/fs/logfs/journal.c

@@ -392,7 +392,7 @@ static int journal_erase_segment(struct logfs_area *area)
 	u64 ofs;
 	int err;
 
-	err = logfs_erase_segment(sb, area->a_segno);
+	err = logfs_erase_segment(sb, area->a_segno, 1);
 	if (err)
 		return err;
 

trunk/fs/logfs/logfs.h

@@ -151,7 +151,8 @@ struct logfs_device_ops {
 	int (*write_sb)(struct super_block *sb, struct page *page);
 	int (*readpage)(void *_sb, struct page *page);
 	void (*writeseg)(struct super_block *sb, u64 ofs, size_t len);
-	int (*erase)(struct super_block *sb, loff_t ofs, size_t len);
+	int (*erase)(struct super_block *sb, loff_t ofs, size_t len,
+			int ensure_write);
 	void (*sync)(struct super_block *sb);
 	void (*put_device)(struct super_block *sb);
 };
@@ -327,6 +328,7 @@ struct logfs_super {
 	u64	 s_feature_compat;
 	u64	 s_feature_flags;
 	u64	 s_sb_ofs[2];
+	struct page *s_erase_page;		/* for dev_bdev.c */
 	/* alias.c fields */
 	struct btree_head32 s_segment_alias;	/* remapped segments */
 	int	 s_no_object_aliases;
@@ -572,7 +574,7 @@ int get_page_reserve(struct inode *inode, struct page *page);
 extern struct logfs_block_ops indirect_block_ops;
 
 /* segment.c */
-int logfs_erase_segment(struct super_block *sb, u32 ofs);
+int logfs_erase_segment(struct super_block *sb, u32 ofs, int ensure_erase);
 int wbuf_read(struct super_block *sb, u64 ofs, size_t len, void *buf);
 int logfs_segment_read(struct inode *inode, struct page *page, u64 ofs, u64 bix,
 		level_t level);

trunk/fs/logfs/segment.c

@@ -25,14 +25,14 @@ static int logfs_mark_segment_bad(struct super_block *sb, u32 segno)
 	return 0;
 }
 
-int logfs_erase_segment(struct super_block *sb, u32 segno)
+int logfs_erase_segment(struct super_block *sb, u32 segno, int ensure_erase)
 {
 	struct logfs_super *super = logfs_super(sb);
 
 	super->s_gec++;
 
 	return super->s_devops->erase(sb, (u64)segno << super->s_segshift,
-			super->s_segsize);
+			super->s_segsize, ensure_erase);
 }
 
 static s64 logfs_get_free_bytes(struct logfs_area *area, size_t bytes)
@@ -798,7 +798,7 @@ static int ostore_erase_segment(struct logfs_area *area)
 	u64 ofs;
 	int err;
 
-	err = logfs_erase_segment(sb, area->a_segno);
+	err = logfs_erase_segment(sb, area->a_segno, 0);
 	if (err)
 		return err;
 

trunk/fs/logfs/super.c

@@ -317,6 +317,7 @@ static int logfs_make_writeable(struct super_block *sb)
 
 static int logfs_get_sb_final(struct super_block *sb, struct vfsmount *mnt)
 {
+	struct logfs_super *super = logfs_super(sb);
 	struct inode *rootdir;
 	int err;
 
@@ -329,15 +330,22 @@ static int logfs_get_sb_final(struct super_block *sb, struct vfsmount *mnt)
 	if (!sb->s_root)
 		goto fail;
 
+	super->s_erase_page = alloc_pages(GFP_KERNEL, 0);
+	if (!super->s_erase_page)
+		goto fail2;
+	memset(page_address(super->s_erase_page), 0xFF, PAGE_SIZE);
+
 	/* FIXME: check for read-only mounts */
 	err = logfs_make_writeable(sb);
 	if (err)
-		goto fail2;
+		goto fail3;
 
 	log_super("LogFS: Finished mounting\n");
 	simple_set_mnt(mnt, sb);
 	return 0;
 
+fail3:
+	__free_page(super->s_erase_page);
 fail2:
 	iput(rootdir);
 fail:
@@ -498,6 +506,8 @@ static void logfs_kill_sb(struct super_block *sb)
 	logfs_cleanup_journal(sb);
 	logfs_cleanup_areas(sb);
 	logfs_cleanup_rw(sb);
+	if (super->s_erase_page)
+		__free_page(super->s_erase_page);
 	super->s_devops->put_device(sb);
 	mempool_destroy(super->s_btree_pool);
 	mempool_destroy(super->s_alias_pool);