1 files changed, 122 insertions, 86 deletions

diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
index 4d2110eafe2..1daea0b4718 100644
--- a/fs/btrfs/compression.c
+++ b/fs/btrfs/compression.c
@@ -32,7 +32,6 @@
 #include <linux/writeback.h>
 #include <linux/bit_spinlock.h>
 #include <linux/slab.h>
-#include "compat.h"
 #include "ctree.h"
 #include "disk-io.h"
 #include "transaction.h"
@@ -82,10 +81,15 @@ struct compressed_bio {
 	u32 sums;
 };
 
+static int btrfs_decompress_biovec(int type, struct page **pages_in,
+				   u64 disk_start, struct bio_vec *bvec,
+				   int vcnt, size_t srclen);
+
 static inline int compressed_bio_size(struct btrfs_root *root,
 				      unsigned long disk_size)
 {
-	u16 csum_size = btrfs_super_csum_size(&root->fs_info->super_copy);
+	u16 csum_size = btrfs_super_csum_size(root->fs_info->super_copy);
+
 	return sizeof(struct compressed_bio) +
 		((disk_size + root->sectorsize - 1) / root->sectorsize) *
 		csum_size;
@@ -105,7 +109,6 @@ static int check_compressed_csum(struct inode *inode,
 				 u64 disk_start)
 {
 	int ret;
-	struct btrfs_root *root = BTRFS_I(inode)->root;
 	struct page *page;
 	unsigned long i;
 	char *kaddr;
@@ -119,17 +122,16 @@ static int check_compressed_csum(struct inode *inode,
 		page = cb->compressed_pages[i];
 		csum = ~(u32)0;
 
-		kaddr = kmap_atomic(page, KM_USER0);
-		csum = btrfs_csum_data(root, kaddr, csum, PAGE_CACHE_SIZE);
+		kaddr = kmap_atomic(page);
+		csum = btrfs_csum_data(kaddr, csum, PAGE_CACHE_SIZE);
 		btrfs_csum_final(csum, (char *)&csum);
-		kunmap_atomic(kaddr, KM_USER0);
+		kunmap_atomic(kaddr);
 
 		if (csum != *cb_sum) {
-			printk(KERN_INFO "btrfs csum failed ino %lu "
-			       "extent %llu csum %u "
-			       "wanted %u mirror %d\n", inode->i_ino,
-			       (unsigned long long)disk_start,
-			       csum, *cb_sum, cb->mirror_num);
+			btrfs_info(BTRFS_I(inode)->root->fs_info,
+			   "csum failed ino %llu extent %llu csum %u wanted %u mirror %d",
+			   btrfs_ino(inode), disk_start, csum, *cb_sum,
+			   cb->mirror_num);
 			ret = -EIO;
 			goto fail;
 		}
@@ -169,7 +171,8 @@ static void end_compressed_bio_read(struct bio *bio, int err)
 		goto out;
 
 	inode = cb->inode;
-	ret = check_compressed_csum(inode, cb, (u64)bio->bi_sector << 9);
+	ret = check_compressed_csum(inode, cb,
+				    (u64)bio->bi_iter.bi_sector << 9);
 	if (ret)
 		goto csum_failed;
 
@@ -198,18 +201,16 @@ csum_failed:
 	if (cb->errors) {
 		bio_io_error(cb->orig_bio);
 	} else {
-		int bio_index = 0;
-		struct bio_vec *bvec = cb->orig_bio->bi_io_vec;
+		int i;
+		struct bio_vec *bvec;
 
 		/*
 		 * we have verified the checksum already, set page
 		 * checked so the end_io handlers know about it
 		 */
-		while (bio_index < cb->orig_bio->bi_vcnt) {
+		bio_for_each_segment_all(bvec, cb->orig_bio, i)
 			SetPageChecked(bvec->bv_page);
-			bvec++;
-			bio_index++;
-		}
+
 		bio_endio(cb->orig_bio, 0);
 	}
 
@@ -224,8 +225,8 @@ out:
  * Clear the writeback bits on all of the file
  * pages for a compressed write
  */
-static noinline int end_compressed_writeback(struct inode *inode, u64 start,
-					     unsigned long ram_size)
+static noinline void end_compressed_writeback(struct inode *inode, u64 start,
+					      unsigned long ram_size)
 {
 	unsigned long index = start >> PAGE_CACHE_SHIFT;
 	unsigned long end_index = (start + ram_size - 1) >> PAGE_CACHE_SHIFT;
@@ -251,7 +252,6 @@ static noinline int end_compressed_writeback(struct inode *inode, u64 start,
 		index += ret;
 	}
 	/* the inode may be gone now */
-	return 0;
 }
 
 /*
@@ -332,14 +332,17 @@ int btrfs_submit_compressed_write(struct inode *inode, u64 start,
 	struct compressed_bio *cb;
 	unsigned long bytes_left;
 	struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
-	int page_index = 0;
+	int pg_index = 0;
 	struct page *page;
 	u64 first_byte = disk_start;
 	struct block_device *bdev;
 	int ret;
+	int skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
 
 	WARN_ON(start & ((u64)PAGE_CACHE_SIZE - 1));
 	cb = kmalloc(compressed_bio_size(root, compressed_len), GFP_NOFS);
+	if (!cb)
+		return -ENOMEM;
 	atomic_set(&cb->pending_bios, 0);
 	cb->errors = 0;
 	cb->inode = inode;
@@ -354,17 +357,21 @@ int btrfs_submit_compressed_write(struct inode *inode, u64 start,
 	bdev = BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
 
 	bio = compressed_bio_alloc(bdev, first_byte, GFP_NOFS);
+	if (!bio) {
+		kfree(cb);
+		return -ENOMEM;
+	}
 	bio->bi_private = cb;
 	bio->bi_end_io = end_compressed_bio_write;
 	atomic_inc(&cb->pending_bios);
 
 	/* create and submit bios for the compressed pages */
 	bytes_left = compressed_len;
-	for (page_index = 0; page_index < cb->nr_pages; page_index++) {
-		page = compressed_pages[page_index];
+	for (pg_index = 0; pg_index < cb->nr_pages; pg_index++) {
+		page = compressed_pages[pg_index];
 		page->mapping = inode->i_mapping;
-		if (bio->bi_size)
-			ret = io_tree->ops->merge_bio_hook(page, 0,
+		if (bio->bi_iter.bi_size)
+			ret = io_tree->ops->merge_bio_hook(WRITE, page, 0,
 							   PAGE_CACHE_SIZE,
 							   bio, 0);
 		else
@@ -383,23 +390,28 @@ int btrfs_submit_compressed_write(struct inode *inode, u64 start,
 			 */
 			atomic_inc(&cb->pending_bios);
 			ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0);
-			BUG_ON(ret);
+			BUG_ON(ret); /* -ENOMEM */
 
-			ret = btrfs_csum_one_bio(root, inode, bio, start, 1);
-			BUG_ON(ret);
+			if (!skip_sum) {
+				ret = btrfs_csum_one_bio(root, inode, bio,
+							 start, 1);
+				BUG_ON(ret); /* -ENOMEM */
+			}
 
 			ret = btrfs_map_bio(root, WRITE, bio, 0, 1);
-			BUG_ON(ret);
+			BUG_ON(ret); /* -ENOMEM */
 
 			bio_put(bio);
 
 			bio = compressed_bio_alloc(bdev, first_byte, GFP_NOFS);
+			BUG_ON(!bio);
 			bio->bi_private = cb;
 			bio->bi_end_io = end_compressed_bio_write;
 			bio_add_page(bio, page, PAGE_CACHE_SIZE, 0);
 		}
 		if (bytes_left < PAGE_CACHE_SIZE) {
-			printk("bytes left %lu compress len %lu nr %lu\n",
+			btrfs_info(BTRFS_I(inode)->root->fs_info,
+					"bytes left %lu compress len %lu nr %lu",
 			       bytes_left, cb->compressed_len, cb->nr_pages);
 		}
 		bytes_left -= PAGE_CACHE_SIZE;
@@ -409,13 +421,15 @@ int btrfs_submit_compressed_write(struct inode *inode, u64 start,
 	bio_get(bio);
 
 	ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0);
-	BUG_ON(ret);
+	BUG_ON(ret); /* -ENOMEM */
 
-	ret = btrfs_csum_one_bio(root, inode, bio, start, 1);
-	BUG_ON(ret);
+	if (!skip_sum) {
+		ret = btrfs_csum_one_bio(root, inode, bio, start, 1);
+		BUG_ON(ret); /* -ENOMEM */
+	}
 
 	ret = btrfs_map_bio(root, WRITE, bio, 0, 1);
-	BUG_ON(ret);
+	BUG_ON(ret); /* -ENOMEM */
 
 	bio_put(bio);
 	return 0;
@@ -426,7 +440,7 @@ static noinline int add_ra_bio_pages(struct inode *inode,
 				     struct compressed_bio *cb)
 {
 	unsigned long end_index;
-	unsigned long page_index;
+	unsigned long pg_index;
 	u64 last_offset;
 	u64 isize = i_size_read(inode);
 	int ret;
@@ -450,15 +464,15 @@ static noinline int add_ra_bio_pages(struct inode *inode,
 	end_index = (i_size_read(inode) - 1) >> PAGE_CACHE_SHIFT;
 
 	while (last_offset < compressed_end) {
-		page_index = last_offset >> PAGE_CACHE_SHIFT;
+		pg_index = last_offset >> PAGE_CACHE_SHIFT;
 
-		if (page_index > end_index)
+		if (pg_index > end_index)
 			break;
 
 		rcu_read_lock();
-		page = radix_tree_lookup(&mapping->page_tree, page_index);
+		page = radix_tree_lookup(&mapping->page_tree, pg_index);
 		rcu_read_unlock();
-		if (page) {
+		if (page && !radix_tree_exceptional_entry(page)) {
 			misses++;
 			if (misses > 4)
 				break;
@@ -470,7 +484,7 @@ static noinline int add_ra_bio_pages(struct inode *inode,
 		if (!page)
 			break;
 
-		if (add_to_page_cache_lru(page, mapping, page_index,
+		if (add_to_page_cache_lru(page, mapping, pg_index,
 								GFP_NOFS)) {
 			page_cache_release(page);
 			goto next;
@@ -483,7 +497,7 @@ static noinline int add_ra_bio_pages(struct inode *inode,
 		 * sure they map to this compressed extent on disk.
 		 */
 		set_page_extent_mapped(page);
-		lock_extent(tree, last_offset, end, GFP_NOFS);
+		lock_extent(tree, last_offset, end);
 		read_lock(&em_tree->lock);
 		em = lookup_extent_mapping(em_tree, last_offset,
 					   PAGE_CACHE_SIZE);
@@ -491,9 +505,9 @@ static noinline int add_ra_bio_pages(struct inode *inode,
 
 		if (!em || last_offset < em->start ||
 		    (last_offset + PAGE_CACHE_SIZE > extent_map_end(em)) ||
-		    (em->block_start >> 9) != cb->orig_bio->bi_sector) {
+		    (em->block_start >> 9) != cb->orig_bio->bi_iter.bi_sector) {
 			free_extent_map(em);
-			unlock_extent(tree, last_offset, end, GFP_NOFS);
+			unlock_extent(tree, last_offset, end);
 			unlock_page(page);
 			page_cache_release(page);
 			break;
@@ -507,10 +521,10 @@ static noinline int add_ra_bio_pages(struct inode *inode,
 			if (zero_offset) {
 				int zeros;
 				zeros = PAGE_CACHE_SIZE - zero_offset;
-				userpage = kmap_atomic(page, KM_USER0);
+				userpage = kmap_atomic(page);
 				memset(userpage + zero_offset, 0, zeros);
 				flush_dcache_page(page);
-				kunmap_atomic(userpage, KM_USER0);
+				kunmap_atomic(userpage);
 			}
 		}
 
@@ -521,7 +535,7 @@ static noinline int add_ra_bio_pages(struct inode *inode,
 			nr_pages++;
 			page_cache_release(page);
 		} else {
-			unlock_extent(tree, last_offset, end, GFP_NOFS);
+			unlock_extent(tree, last_offset, end);
 			unlock_page(page);
 			page_cache_release(page);
 			break;
@@ -537,7 +551,7 @@ next:
  * in it.  We don't actually do IO on those pages but allocate new ones
  * to hold the compressed pages on disk.
  *
- * bio->bi_sector points to the compressed extent on disk
+ * bio->bi_iter.bi_sector points to the compressed extent on disk
  * bio->bi_io_vec points to all of the inode pages
  * bio->bi_vcnt is a count of pages
  *
@@ -554,15 +568,16 @@ int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
 	unsigned long uncompressed_len = bio->bi_vcnt * PAGE_CACHE_SIZE;
 	unsigned long compressed_len;
 	unsigned long nr_pages;
-	unsigned long page_index;
+	unsigned long pg_index;
 	struct page *page;
 	struct block_device *bdev;
 	struct bio *comp_bio;
-	u64 cur_disk_byte = (u64)bio->bi_sector << 9;
+	u64 cur_disk_byte = (u64)bio->bi_iter.bi_sector << 9;
 	u64 em_len;
 	u64 em_start;
 	struct extent_map *em;
 	int ret = -ENOMEM;
+	int faili = 0;
 	u32 *sums;
 
 	tree = &BTRFS_I(inode)->io_tree;
@@ -574,6 +589,8 @@ int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
 				   page_offset(bio->bi_io_vec->bv_page),
 				   PAGE_CACHE_SIZE);
 	read_unlock(&em_tree->lock);
+	if (!em)
+		return -EIO;
 
 	compressed_len = em->block_len;
 	cb = kmalloc(compressed_bio_size(root, compressed_len), GFP_NOFS);
@@ -607,15 +624,23 @@ int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
 
 	bdev = BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
 
-	for (page_index = 0; page_index < nr_pages; page_index++) {
-		cb->compressed_pages[page_index] = alloc_page(GFP_NOFS |
+	for (pg_index = 0; pg_index < nr_pages; pg_index++) {
+		cb->compressed_pages[pg_index] = alloc_page(GFP_NOFS |
 							      __GFP_HIGHMEM);
-		if (!cb->compressed_pages[page_index])
+		if (!cb->compressed_pages[pg_index]) {
+			faili = pg_index - 1;
+			ret = -ENOMEM;
 			goto fail2;
+		}
 	}
+	faili = nr_pages - 1;
 	cb->nr_pages = nr_pages;
 
-	add_ra_bio_pages(inode, em_start + em_len, cb);
+	/* In the parent-locked case, we only locked the range we are
+	 * interested in.  In all other cases, we can opportunistically
+	 * cache decompressed data that goes beyond the requested range. */
+	if (!(bio_flags & EXTENT_BIO_PARENT_LOCKED))
+		add_ra_bio_pages(inode, em_start + em_len, cb);
 
 	/* include any pages we added in add_ra-bio_pages */
 	uncompressed_len = bio->bi_vcnt * PAGE_CACHE_SIZE;
@@ -628,13 +653,13 @@ int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
 	comp_bio->bi_end_io = end_compressed_bio_read;
 	atomic_inc(&cb->pending_bios);
 
-	for (page_index = 0; page_index < nr_pages; page_index++) {
-		page = cb->compressed_pages[page_index];
+	for (pg_index = 0; pg_index < nr_pages; pg_index++) {
+		page = cb->compressed_pages[pg_index];
 		page->mapping = inode->i_mapping;
 		page->index = em_start >> PAGE_CACHE_SHIFT;
 
-		if (comp_bio->bi_size)
-			ret = tree->ops->merge_bio_hook(page, 0,
+		if (comp_bio->bi_iter.bi_size)
+			ret = tree->ops->merge_bio_hook(READ, page, 0,
 							PAGE_CACHE_SIZE,
 							comp_bio, 0);
 		else
@@ -646,7 +671,7 @@ int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
 			bio_get(comp_bio);
 
 			ret = btrfs_bio_wq_end_io(root->fs_info, comp_bio, 0);
-			BUG_ON(ret);
+			BUG_ON(ret); /* -ENOMEM */
 
 			/*
 			 * inc the count before we submit the bio so
@@ -657,20 +682,23 @@ int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
 			atomic_inc(&cb->pending_bios);
 
 			if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) {
-				btrfs_lookup_bio_sums(root, inode, comp_bio,
-						      sums);
+				ret = btrfs_lookup_bio_sums(root, inode,
+							comp_bio, sums);
+				BUG_ON(ret); /* -ENOMEM */
 			}
-			sums += (comp_bio->bi_size + root->sectorsize - 1) /
-				root->sectorsize;
+			sums += (comp_bio->bi_iter.bi_size +
+				 root->sectorsize - 1) / root->sectorsize;
 
 			ret = btrfs_map_bio(root, READ, comp_bio,
 					    mirror_num, 0);
-			BUG_ON(ret);
+			if (ret)
+				bio_endio(comp_bio, ret);
 
 			bio_put(comp_bio);
 
 			comp_bio = compressed_bio_alloc(bdev, cur_disk_byte,
 							GFP_NOFS);
+			BUG_ON(!comp_bio);
 			comp_bio->bi_private = cb;
 			comp_bio->bi_end_io = end_compressed_bio_read;
 
@@ -681,20 +709,25 @@ int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
 	bio_get(comp_bio);
 
 	ret = btrfs_bio_wq_end_io(root->fs_info, comp_bio, 0);
-	BUG_ON(ret);
+	BUG_ON(ret); /* -ENOMEM */
 
-	if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM))
-		btrfs_lookup_bio_sums(root, inode, comp_bio, sums);
+	if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) {
+		ret = btrfs_lookup_bio_sums(root, inode, comp_bio, sums);
+		BUG_ON(ret); /* -ENOMEM */
+	}
 
 	ret = btrfs_map_bio(root, READ, comp_bio, mirror_num, 0);
-	BUG_ON(ret);
+	if (ret)
+		bio_endio(comp_bio, ret);
 
 	bio_put(comp_bio);
 	return 0;
 
 fail2:
-	for (page_index = 0; page_index < nr_pages; page_index++)
-		free_page((unsigned long)cb->compressed_pages[page_index]);
+	while (faili >= 0) {
+		__free_page(cb->compressed_pages[faili]);
+		faili--;
+	}
 
 	kfree(cb->compressed_pages);
 fail1:
@@ -710,12 +743,12 @@ static int comp_num_workspace[BTRFS_COMPRESS_TYPES];
 static atomic_t comp_alloc_workspace[BTRFS_COMPRESS_TYPES];
 static wait_queue_head_t comp_workspace_wait[BTRFS_COMPRESS_TYPES];
 
-struct btrfs_compress_op *btrfs_compress_op[] = {
+static struct btrfs_compress_op *btrfs_compress_op[] = {
 	&btrfs_zlib_compress,
 	&btrfs_lzo_compress,
 };
 
-int __init btrfs_init_compress(void)
+void __init btrfs_init_compress(void)
 {
 	int i;
 
@@ -725,7 +758,6 @@ int __init btrfs_init_compress(void)
 		atomic_set(&comp_alloc_workspace[i], 0);
 		init_waitqueue_head(&comp_workspace_wait[i]);
 	}
-	return 0;
 }
 
 /*
@@ -789,7 +821,7 @@ static void free_workspace(int type, struct list_head *workspace)
 
 	spin_lock(workspace_lock);
 	if (*num_workspace < num_online_cpus()) {
-		list_add_tail(workspace, idle_workspace);
+		list_add(workspace, idle_workspace);
 		(*num_workspace)++;
 		spin_unlock(workspace_lock);
 		goto wake;
@@ -799,6 +831,7 @@ static void free_workspace(int type, struct list_head *workspace)
 	btrfs_compress_op[idx]->free_workspace(workspace);
 	atomic_dec(alloc_workspace);
 wake:
+	smp_mb();
 	if (waitqueue_active(workspace_wait))
 		wake_up(workspace_wait);
 }
@@ -854,7 +887,7 @@ int btrfs_compress_pages(int type, struct address_space *mapping,
 
 	workspace = find_workspace(type);
 	if (IS_ERR(workspace))
-		return -1;
+		return PTR_ERR(workspace);
 
 	ret = btrfs_compress_op[type-1]->compress_pages(workspace, mapping,
 						      start, len, pages,
@@ -881,15 +914,16 @@ int btrfs_compress_pages(int type, struct address_space *mapping,
  * be contiguous.  They all correspond to the range of bytes covered by
  * the compressed extent.
  */
-int btrfs_decompress_biovec(int type, struct page **pages_in, u64 disk_start,
-			    struct bio_vec *bvec, int vcnt, size_t srclen)
+static int btrfs_decompress_biovec(int type, struct page **pages_in,
+				   u64 disk_start, struct bio_vec *bvec,
+				   int vcnt, size_t srclen)
 {
 	struct list_head *workspace;
 	int ret;
 
 	workspace = find_workspace(type);
 	if (IS_ERR(workspace))
-		return -ENOMEM;
+		return PTR_ERR(workspace);
 
 	ret = btrfs_compress_op[type-1]->decompress_biovec(workspace, pages_in,
 							 disk_start,
@@ -911,7 +945,7 @@ int btrfs_decompress(int type, unsigned char *data_in, struct page *dest_page,
 
 	workspace = find_workspace(type);
 	if (IS_ERR(workspace))
-		return -ENOMEM;
+		return PTR_ERR(workspace);
 
 	ret = btrfs_compress_op[type-1]->decompress(workspace, data_in,
 						  dest_page, start_byte,
@@ -936,7 +970,7 @@ void btrfs_exit_compress(void)
 int btrfs_decompress_buf2page(char *buf, unsigned long buf_start,
 			      unsigned long total_out, u64 disk_start,
 			      struct bio_vec *bvec, int vcnt,
-			      unsigned long *page_index,
+			      unsigned long *pg_index,
 			      unsigned long *pg_offset)
 {
 	unsigned long buf_offset;
@@ -945,7 +979,7 @@ int btrfs_decompress_buf2page(char *buf, unsigned long buf_start,
 	unsigned long working_bytes = total_out - buf_start;
 	unsigned long bytes;
 	char *kaddr;
-	struct page *page_out = bvec[*page_index].bv_page;
+	struct page *page_out = bvec[*pg_index].bv_page;
 
 	/*
 	 * start byte is the first byte of the page we're currently
@@ -974,9 +1008,11 @@ int btrfs_decompress_buf2page(char *buf, unsigned long buf_start,
 		bytes = min(PAGE_CACHE_SIZE - *pg_offset,
 			    PAGE_CACHE_SIZE - buf_offset);
 		bytes = min(bytes, working_bytes);
-		kaddr = kmap_atomic(page_out, KM_USER0);
+		kaddr = kmap_atomic(page_out);
 		memcpy(kaddr + *pg_offset, buf + buf_offset, bytes);
-		kunmap_atomic(kaddr, KM_USER0);
+		if (*pg_index == (vcnt - 1) && *pg_offset == 0)
+			memset(kaddr + bytes, 0, PAGE_CACHE_SIZE - bytes);
+		kunmap_atomic(kaddr);
 		flush_dcache_page(page_out);
 
 		*pg_offset += bytes;
@@ -986,11 +1022,11 @@ int btrfs_decompress_buf2page(char *buf, unsigned long buf_start,
 
 		/* check if we need to pick another page */
 		if (*pg_offset == PAGE_CACHE_SIZE) {
-			(*page_index)++;
-			if (*page_index >= vcnt)
+			(*pg_index)++;
+			if (*pg_index >= vcnt)
 				return 0;
 
-			page_out = bvec[*page_index].bv_page;
+			page_out = bvec[*pg_index].bv_page;
 			*pg_offset = 0;
 			start_byte = page_offset(page_out) - disk_start;