1 files changed, 115 insertions, 104 deletions

diff --git a/fs/btrfs/raid56.c b/fs/btrfs/raid56.c
index cdd373c27784..3ff2bedfb3a4 100644
--- a/fs/btrfs/raid56.c
+++ b/fs/btrfs/raid56.c
@@ -134,14 +134,17 @@ struct btrfs_stripe_hash_table {
 };
 
 /*
- * A bvec like structure to present a sector inside a page.
- *
- * Unlike bvec we don't need bvlen, as it's fixed to sectorsize.
+ * A structure to present a sector inside a page, the length is fixed to
+ * sectorsize;
  */
 struct sector_ptr {
-	struct page *page;
-	unsigned int pgoff:24;
-	unsigned int uptodate:8;
+	/*
+	 * Blocks from the bio list can still be highmem.
+	 * So here we use physical address to present a page and the offset inside it.
+	 */
+	phys_addr_t paddr;
+	bool has_paddr;
+	bool uptodate;
 };
 
 static void rmw_rbio_work(struct work_struct *work);
@@ -200,8 +203,7 @@ int btrfs_alloc_stripe_hash_table(struct btrfs_fs_info *info)
 	struct btrfs_stripe_hash_table *x;
 	struct btrfs_stripe_hash *cur;
 	struct btrfs_stripe_hash *h;
-	int num_entries = 1 << BTRFS_STRIPE_HASH_TABLE_BITS;
-	int i;
+	unsigned int num_entries = 1U << BTRFS_STRIPE_HASH_TABLE_BITS;
 
 	if (info->stripe_hash_table)
 		return 0;
@@ -222,7 +224,7 @@ int btrfs_alloc_stripe_hash_table(struct btrfs_fs_info *info)
 
 	h = table->table;
 
-	for (i = 0; i < num_entries; i++) {
+	for (unsigned int i = 0; i < num_entries; i++) {
 		cur = h + i;
 		INIT_LIST_HEAD(&cur->hash_list);
 		spin_lock_init(&cur->lock);
@@ -233,6 +235,14 @@ int btrfs_alloc_stripe_hash_table(struct btrfs_fs_info *info)
 	return 0;
 }
 
+static void memcpy_sectors(const struct sector_ptr *dst,
+			   const struct sector_ptr *src, u32 blocksize)
+{
+	memcpy_page(phys_to_page(dst->paddr), offset_in_page(dst->paddr),
+		    phys_to_page(src->paddr), offset_in_page(src->paddr),
+		    blocksize);
+}
+
 /*
  * caching an rbio means to copy anything from the
  * bio_sectors array into the stripe_pages array.  We
@@ -253,7 +263,7 @@ static void cache_rbio_pages(struct btrfs_raid_bio *rbio)
 
 	for (i = 0; i < rbio->nr_sectors; i++) {
 		/* Some range not covered by bio (partial write), skip it */
-		if (!rbio->bio_sectors[i].page) {
+		if (!rbio->bio_sectors[i].has_paddr) {
 			/*
 			 * Even if the sector is not covered by bio, if it is
 			 * a data sector it should still be uptodate as it is
@@ -264,12 +274,8 @@ static void cache_rbio_pages(struct btrfs_raid_bio *rbio)
 			continue;
 		}
 
-		ASSERT(rbio->stripe_sectors[i].page);
-		memcpy_page(rbio->stripe_sectors[i].page,
-			    rbio->stripe_sectors[i].pgoff,
-			    rbio->bio_sectors[i].page,
-			    rbio->bio_sectors[i].pgoff,
-			    rbio->bioc->fs_info->sectorsize);
+		memcpy_sectors(&rbio->stripe_sectors[i], &rbio->bio_sectors[i],
+				rbio->bioc->fs_info->sectorsize);
 		rbio->stripe_sectors[i].uptodate = 1;
 	}
 	set_bit(RBIO_CACHE_READY_BIT, &rbio->flags);
@@ -326,8 +332,13 @@ static void index_stripe_sectors(struct btrfs_raid_bio *rbio)
 		int page_index = offset >> PAGE_SHIFT;
 
 		ASSERT(page_index < rbio->nr_pages);
-		rbio->stripe_sectors[i].page = rbio->stripe_pages[page_index];
-		rbio->stripe_sectors[i].pgoff = offset_in_page(offset);
+		if (!rbio->stripe_pages[page_index])
+			continue;
+
+		rbio->stripe_sectors[i].has_paddr = true;
+		rbio->stripe_sectors[i].paddr =
+			page_to_phys(rbio->stripe_pages[page_index]) +
+			offset_in_page(offset);
 	}
 }
 
@@ -507,9 +518,8 @@ static void btrfs_clear_rbio_cache(struct btrfs_fs_info *info)
 
 	spin_lock(&table->cache_lock);
 	while (!list_empty(&table->stripe_cache)) {
-		rbio = list_entry(table->stripe_cache.next,
-				  struct btrfs_raid_bio,
-				  stripe_cache);
+		rbio = list_first_entry(&table->stripe_cache,
+					struct btrfs_raid_bio, stripe_cache);
 		__remove_rbio_from_cache(rbio);
 	}
 	spin_unlock(&table->cache_lock);
@@ -567,9 +577,9 @@ static void cache_rbio(struct btrfs_raid_bio *rbio)
 	if (table->cache_size > RBIO_CACHE_SIZE) {
 		struct btrfs_raid_bio *found;
 
-		found = list_entry(table->stripe_cache.prev,
-				  struct btrfs_raid_bio,
-				  stripe_cache);
+		found = list_last_entry(&table->stripe_cache,
+					struct btrfs_raid_bio,
+					stripe_cache);
 
 		if (found != rbio)
 			__remove_rbio_from_cache(found);
@@ -882,14 +892,14 @@ done_nolock:
 		remove_rbio_from_cache(rbio);
 }
 
-static void rbio_endio_bio_list(struct bio *cur, blk_status_t err)
+static void rbio_endio_bio_list(struct bio *cur, blk_status_t status)
 {
 	struct bio *next;
 
 	while (cur) {
 		next = cur->bi_next;
 		cur->bi_next = NULL;
-		cur->bi_status = err;
+		cur->bi_status = status;
 		bio_endio(cur);
 		cur = next;
 	}
@@ -899,7 +909,7 @@ static void rbio_endio_bio_list(struct bio *cur, blk_status_t err)
  * this frees the rbio and runs through all the bios in the
  * bio_list and calls end_io on them
  */
-static void rbio_orig_end_io(struct btrfs_raid_bio *rbio, blk_status_t err)
+static void rbio_orig_end_io(struct btrfs_raid_bio *rbio, blk_status_t status)
 {
 	struct bio *cur = bio_list_get(&rbio->bio_list);
 	struct bio *extra;
@@ -928,9 +938,9 @@ static void rbio_orig_end_io(struct btrfs_raid_bio *rbio, blk_status_t err)
 	extra = bio_list_get(&rbio->bio_list);
 	free_raid_bio(rbio);
 
-	rbio_endio_bio_list(cur, err);
+	rbio_endio_bio_list(cur, status);
 	if (extra)
-		rbio_endio_bio_list(extra, err);
+		rbio_endio_bio_list(extra, status);
 }
 
 /*
@@ -962,9 +972,9 @@ static struct sector_ptr *sector_in_rbio(struct btrfs_raid_bio *rbio,
 
 	spin_lock(&rbio->bio_list_lock);
 	sector = &rbio->bio_sectors[index];
-	if (sector->page || bio_list_only) {
+	if (sector->has_paddr || bio_list_only) {
 		/* Don't return sector without a valid page pointer */
-		if (!sector->page)
+		if (!sector->has_paddr)
 			sector = NULL;
 		spin_unlock(&rbio->bio_list_lock);
 		return sector;
@@ -1142,7 +1152,7 @@ static int rbio_add_io_sector(struct btrfs_raid_bio *rbio,
 			   rbio, stripe_nr);
 	ASSERT_RBIO_SECTOR(sector_nr >= 0 && sector_nr < rbio->stripe_nsectors,
 			   rbio, sector_nr);
-	ASSERT(sector->page);
+	ASSERT(sector->has_paddr);
 
 	stripe = &rbio->bioc->stripes[stripe_nr];
 	disk_start = stripe->physical + sector_nr * sectorsize;
@@ -1173,8 +1183,8 @@ static int rbio_add_io_sector(struct btrfs_raid_bio *rbio,
 		 */
 		if (last_end == disk_start && !last->bi_status &&
 		    last->bi_bdev == stripe->dev->bdev) {
-			ret = bio_add_page(last, sector->page, sectorsize,
-					   sector->pgoff);
+			ret = bio_add_page(last, phys_to_page(sector->paddr),
+					   sectorsize, offset_in_page(sector->paddr));
 			if (ret == sectorsize)
 				return 0;
 		}
@@ -1187,7 +1197,8 @@ static int rbio_add_io_sector(struct btrfs_raid_bio *rbio,
 	bio->bi_iter.bi_sector = disk_start >> SECTOR_SHIFT;
 	bio->bi_private = rbio;
 
-	__bio_add_page(bio, sector->page, sectorsize, sector->pgoff);
+	__bio_add_page(bio, phys_to_page(sector->paddr), sectorsize,
+		       offset_in_page(sector->paddr));
 	bio_list_add(bio_list, bio);
 	return 0;
 }
@@ -1195,23 +1206,20 @@ static int rbio_add_io_sector(struct btrfs_raid_bio *rbio,
 static void index_one_bio(struct btrfs_raid_bio *rbio, struct bio *bio)
 {
 	const u32 sectorsize = rbio->bioc->fs_info->sectorsize;
-	struct bio_vec bvec;
-	struct bvec_iter iter;
+	const u32 sectorsize_bits = rbio->bioc->fs_info->sectorsize_bits;
+	struct bvec_iter iter = bio->bi_iter;
 	u32 offset = (bio->bi_iter.bi_sector << SECTOR_SHIFT) -
 		     rbio->bioc->full_stripe_logical;
 
-	bio_for_each_segment(bvec, bio, iter) {
-		u32 bvec_offset;
-
-		for (bvec_offset = 0; bvec_offset < bvec.bv_len;
-		     bvec_offset += sectorsize, offset += sectorsize) {
-			int index = offset / sectorsize;
-			struct sector_ptr *sector = &rbio->bio_sectors[index];
+	while (iter.bi_size) {
+		unsigned int index = (offset >> sectorsize_bits);
+		struct sector_ptr *sector = &rbio->bio_sectors[index];
+		struct bio_vec bv = bio_iter_iovec(bio, iter);
 
-			sector->page = bvec.bv_page;
-			sector->pgoff = bvec.bv_offset + bvec_offset;
-			ASSERT(sector->pgoff < PAGE_SIZE);
-		}
+		sector->has_paddr = true;
+		sector->paddr = bvec_phys(&bv);
+		bio_advance_iter_single(bio, &iter, sectorsize);
+		offset += sectorsize;
 	}
 }
 
@@ -1289,6 +1297,15 @@ static void assert_rbio(struct btrfs_raid_bio *rbio)
 	ASSERT_RBIO(rbio->nr_data < rbio->real_stripes, rbio);
 }
 
+static inline void *kmap_local_sector(const struct sector_ptr *sector)
+{
+	/* The sector pointer must have a page mapped to it. */
+	ASSERT(sector->has_paddr);
+
+	return kmap_local_page(phys_to_page(sector->paddr)) +
+	       offset_in_page(sector->paddr);
+}
+
 /* Generate PQ for one vertical stripe. */
 static void generate_pq_vertical(struct btrfs_raid_bio *rbio, int sectornr)
 {
@@ -1301,14 +1318,13 @@ static void generate_pq_vertical(struct btrfs_raid_bio *rbio, int sectornr)
 	/* First collect one sector from each data stripe */
 	for (stripe = 0; stripe < rbio->nr_data; stripe++) {
 		sector = sector_in_rbio(rbio, stripe, sectornr, 0);
-		pointers[stripe] = kmap_local_page(sector->page) +
-				   sector->pgoff;
+		pointers[stripe] = kmap_local_sector(sector);
 	}
 
 	/* Then add the parity stripe */
 	sector = rbio_pstripe_sector(rbio, sectornr);
 	sector->uptodate = 1;
-	pointers[stripe++] = kmap_local_page(sector->page) + sector->pgoff;
+	pointers[stripe++] = kmap_local_sector(sector);
 
 	if (has_qstripe) {
 		/*
@@ -1317,8 +1333,7 @@ static void generate_pq_vertical(struct btrfs_raid_bio *rbio, int sectornr)
 		 */
 		sector = rbio_qstripe_sector(rbio, sectornr);
 		sector->uptodate = 1;
-		pointers[stripe++] = kmap_local_page(sector->page) +
-				     sector->pgoff;
+		pointers[stripe++] = kmap_local_sector(sector);
 
 		assert_rbio(rbio);
 		raid6_call.gen_syndrome(rbio->real_stripes, sectorsize,
@@ -1477,15 +1492,14 @@ static void set_rbio_range_error(struct btrfs_raid_bio *rbio, struct bio *bio)
  * stripe_pages[], thus we need to locate the sector.
  */
 static struct sector_ptr *find_stripe_sector(struct btrfs_raid_bio *rbio,
-					     struct page *page,
-					     unsigned int pgoff)
+					     phys_addr_t paddr)
 {
 	int i;
 
 	for (i = 0; i < rbio->nr_sectors; i++) {
 		struct sector_ptr *sector = &rbio->stripe_sectors[i];
 
-		if (sector->page == page && sector->pgoff == pgoff)
+		if (sector->has_paddr && sector->paddr == paddr)
 			return sector;
 	}
 	return NULL;
@@ -1505,11 +1519,10 @@ static void set_bio_pages_uptodate(struct btrfs_raid_bio *rbio, struct bio *bio)
 
 	bio_for_each_segment_all(bvec, bio, iter_all) {
 		struct sector_ptr *sector;
-		int pgoff;
+		phys_addr_t paddr = bvec_phys(bvec);
 
-		for (pgoff = bvec->bv_offset; pgoff - bvec->bv_offset < bvec->bv_len;
-		     pgoff += sectorsize) {
-			sector = find_stripe_sector(rbio, bvec->bv_page, pgoff);
+		for (u32 off = 0; off < bvec->bv_len; off += sectorsize) {
+			sector = find_stripe_sector(rbio, paddr + off);
 			ASSERT(sector);
 			if (sector)
 				sector->uptodate = 1;
@@ -1519,17 +1532,14 @@ static void set_bio_pages_uptodate(struct btrfs_raid_bio *rbio, struct bio *bio)
 
 static int get_bio_sector_nr(struct btrfs_raid_bio *rbio, struct bio *bio)
 {
-	struct bio_vec *bv = bio_first_bvec_all(bio);
+	phys_addr_t bvec_paddr = bvec_phys(bio_first_bvec_all(bio));
 	int i;
 
 	for (i = 0; i < rbio->nr_sectors; i++) {
-		struct sector_ptr *sector;
-
-		sector = &rbio->stripe_sectors[i];
-		if (sector->page == bv->bv_page && sector->pgoff == bv->bv_offset)
+		if (rbio->stripe_sectors[i].paddr == bvec_paddr)
 			break;
-		sector = &rbio->bio_sectors[i];
-		if (sector->page == bv->bv_page && sector->pgoff == bv->bv_offset)
+		if (rbio->bio_sectors[i].has_paddr &&
+		    rbio->bio_sectors[i].paddr == bvec_paddr)
 			break;
 	}
 	ASSERT(i < rbio->nr_sectors);
@@ -1575,11 +1585,11 @@ static void verify_bio_data_sectors(struct btrfs_raid_bio *rbio,
 		return;
 
 	bio_for_each_segment_all(bvec, bio, iter_all) {
-		int bv_offset;
+		void *kaddr;
 
-		for (bv_offset = bvec->bv_offset;
-		     bv_offset < bvec->bv_offset + bvec->bv_len;
-		     bv_offset += fs_info->sectorsize, total_sector_nr++) {
+		kaddr = bvec_kmap_local(bvec);
+		for (u32 off = 0; off < bvec->bv_len;
+		     off += fs_info->sectorsize, total_sector_nr++) {
 			u8 csum_buf[BTRFS_CSUM_SIZE];
 			u8 *expected_csum = rbio->csum_buf +
 					    total_sector_nr * fs_info->csum_size;
@@ -1589,11 +1599,12 @@ static void verify_bio_data_sectors(struct btrfs_raid_bio *rbio,
 			if (!test_bit(total_sector_nr, rbio->csum_bitmap))
 				continue;
 
-			ret = btrfs_check_sector_csum(fs_info, bvec->bv_page,
-				bv_offset, csum_buf, expected_csum);
+			ret = btrfs_check_sector_csum(fs_info, kaddr + off,
+						      csum_buf, expected_csum);
 			if (ret < 0)
 				set_bit(total_sector_nr, rbio->error_bitmap);
 		}
+		kunmap_local(kaddr);
 	}
 }
 
@@ -1689,8 +1700,8 @@ static void raid_unplug(struct blk_plug_cb *cb, bool from_schedule)
 	list_sort(NULL, &plug->rbio_list, plug_cmp);
 
 	while (!list_empty(&plug->rbio_list)) {
-		cur = list_entry(plug->rbio_list.next,
-				 struct btrfs_raid_bio, plug_list);
+		cur = list_first_entry(&plug->rbio_list,
+				       struct btrfs_raid_bio, plug_list);
 		list_del_init(&cur->plug_list);
 
 		if (rbio_is_full(cur)) {
@@ -1791,6 +1802,7 @@ static int verify_one_sector(struct btrfs_raid_bio *rbio,
 	struct sector_ptr *sector;
 	u8 csum_buf[BTRFS_CSUM_SIZE];
 	u8 *csum_expected;
+	void *kaddr;
 	int ret;
 
 	if (!rbio->csum_bitmap || !rbio->csum_buf)
@@ -1809,13 +1821,12 @@ static int verify_one_sector(struct btrfs_raid_bio *rbio,
 		sector = rbio_stripe_sector(rbio, stripe_nr, sector_nr);
 	}
 
-	ASSERT(sector->page);
-
 	csum_expected = rbio->csum_buf +
 			(stripe_nr * rbio->stripe_nsectors + sector_nr) *
 			fs_info->csum_size;
-	ret = btrfs_check_sector_csum(fs_info, sector->page, sector->pgoff,
-				      csum_buf, csum_expected);
+	kaddr = kmap_local_sector(sector);
+	ret = btrfs_check_sector_csum(fs_info, kaddr, csum_buf, csum_expected);
+	kunmap_local(kaddr);
 	return ret;
 }
 
@@ -1872,9 +1883,7 @@ static int recover_vertical(struct btrfs_raid_bio *rbio, int sector_nr,
 		} else {
 			sector = rbio_stripe_sector(rbio, stripe_nr, sector_nr);
 		}
-		ASSERT(sector->page);
-		pointers[stripe_nr] = kmap_local_page(sector->page) +
-				   sector->pgoff;
+		pointers[stripe_nr] = kmap_local_sector(sector);
 		unmap_array[stripe_nr] = pointers[stripe_nr];
 	}
 
@@ -2282,9 +2291,8 @@ static int rmw_read_wait_recover(struct btrfs_raid_bio *rbio)
 static void raid_wait_write_end_io(struct bio *bio)
 {
 	struct btrfs_raid_bio *rbio = bio->bi_private;
-	blk_status_t err = bio->bi_status;
 
-	if (err)
+	if (bio->bi_status)
 		rbio_update_error_bitmap(rbio, bio);
 	bio_put(bio);
 	if (atomic_dec_and_test(&rbio->stripes_pending))
@@ -2326,7 +2334,7 @@ static bool need_read_stripe_sectors(struct btrfs_raid_bio *rbio)
 		 * thus this rbio can not be cached one, as cached one must
 		 * have all its data sectors present and uptodate.
 		 */
-		if (!sector->page || !sector->uptodate)
+		if (!sector->has_paddr || !sector->uptodate)
 			return true;
 	}
 	return false;
@@ -2516,6 +2524,7 @@ static int finish_parity_scrub(struct btrfs_raid_bio *rbio)
 	int stripe;
 	int sectornr;
 	bool has_qstripe;
+	struct page *page;
 	struct sector_ptr p_sector = { 0 };
 	struct sector_ptr q_sector = { 0 };
 	struct bio_list bio_list;
@@ -2547,29 +2556,33 @@ static int finish_parity_scrub(struct btrfs_raid_bio *rbio)
 	 */
 	clear_bit(RBIO_CACHE_READY_BIT, &rbio->flags);
 
-	p_sector.page = alloc_page(GFP_NOFS);
-	if (!p_sector.page)
+	page = alloc_page(GFP_NOFS);
+	if (!page)
 		return -ENOMEM;
-	p_sector.pgoff = 0;
+	p_sector.has_paddr = true;
+	p_sector.paddr = page_to_phys(page);
 	p_sector.uptodate = 1;
+	page = NULL;
 
 	if (has_qstripe) {
 		/* RAID6, allocate and map temp space for the Q stripe */
-		q_sector.page = alloc_page(GFP_NOFS);
-		if (!q_sector.page) {
-			__free_page(p_sector.page);
-			p_sector.page = NULL;
+		page = alloc_page(GFP_NOFS);
+		if (!page) {
+			__free_page(phys_to_page(p_sector.paddr));
+			p_sector.has_paddr = false;
 			return -ENOMEM;
 		}
-		q_sector.pgoff = 0;
+		q_sector.has_paddr = true;
+		q_sector.paddr = page_to_phys(page);
 		q_sector.uptodate = 1;
-		pointers[rbio->real_stripes - 1] = kmap_local_page(q_sector.page);
+		page = NULL;
+		pointers[rbio->real_stripes - 1] = kmap_local_sector(&q_sector);
 	}
 
 	bitmap_clear(rbio->error_bitmap, 0, rbio->nr_sectors);
 
 	/* Map the parity stripe just once */
-	pointers[nr_data] = kmap_local_page(p_sector.page);
+	pointers[nr_data] = kmap_local_sector(&p_sector);
 
 	for_each_set_bit(sectornr, &rbio->dbitmap, rbio->stripe_nsectors) {
 		struct sector_ptr *sector;
@@ -2578,8 +2591,7 @@ static int finish_parity_scrub(struct btrfs_raid_bio *rbio)
 		/* first collect one page from each data stripe */
 		for (stripe = 0; stripe < nr_data; stripe++) {
 			sector = sector_in_rbio(rbio, stripe, sectornr, 0);
-			pointers[stripe] = kmap_local_page(sector->page) +
-					   sector->pgoff;
+			pointers[stripe] = kmap_local_sector(sector);
 		}
 
 		if (has_qstripe) {
@@ -2595,7 +2607,7 @@ static int finish_parity_scrub(struct btrfs_raid_bio *rbio)
 
 		/* Check scrubbing parity and repair it */
 		sector = rbio_stripe_sector(rbio, rbio->scrubp, sectornr);
-		parity = kmap_local_page(sector->page) + sector->pgoff;
+		parity = kmap_local_sector(sector);
 		if (memcmp(parity, pointers[rbio->scrubp], sectorsize) != 0)
 			memcpy(parity, pointers[rbio->scrubp], sectorsize);
 		else
@@ -2608,12 +2620,11 @@ static int finish_parity_scrub(struct btrfs_raid_bio *rbio)
 	}
 
 	kunmap_local(pointers[nr_data]);
-	__free_page(p_sector.page);
-	p_sector.page = NULL;
-	if (q_sector.page) {
-		kunmap_local(pointers[rbio->real_stripes - 1]);
-		__free_page(q_sector.page);
-		q_sector.page = NULL;
+	__free_page(phys_to_page(p_sector.paddr));
+	p_sector.has_paddr = false;
+	if (q_sector.has_paddr) {
+		__free_page(phys_to_page(q_sector.paddr));
+		q_sector.has_paddr = false;
 	}
 
 	/*