1 files changed, 66 insertions, 92 deletions

diff --git a/fs/btrfs/zstd.c b/fs/btrfs/zstd.c
index 5511766485cd..2b232b82c3a8 100644
--- a/fs/btrfs/zstd.c
+++ b/fs/btrfs/zstd.c
@@ -18,8 +18,9 @@
 #include <linux/slab.h>
 #include <linux/zstd.h>
 #include "misc.h"
+#include "fs.h"
 #include "compression.h"
-#include "ctree.h"
+#include "super.h"
 
 #define ZSTD_BTRFS_MAX_WINDOWLOG 17
 #define ZSTD_BTRFS_MAX_INPUT (1 << ZSTD_BTRFS_MAX_WINDOWLOG)
@@ -373,25 +374,25 @@ fail:
 	return ERR_PTR(-ENOMEM);
 }
 
-int zstd_compress_pages(struct list_head *ws, struct address_space *mapping,
-		u64 start, struct page **pages, unsigned long *out_pages,
-		unsigned long *total_in, unsigned long *total_out)
+int zstd_compress_folios(struct list_head *ws, struct address_space *mapping,
+			 u64 start, struct folio **folios, unsigned long *out_folios,
+			 unsigned long *total_in, unsigned long *total_out)
 {
 	struct workspace *workspace = list_entry(ws, struct workspace, list);
 	zstd_cstream *stream;
 	int ret = 0;
-	int nr_pages = 0;
-	struct page *in_page = NULL;  /* The current page to read */
-	struct page *out_page = NULL; /* The current page to write to */
+	int nr_folios = 0;
+	struct folio *in_folio = NULL;  /* The current folio to read. */
+	struct folio *out_folio = NULL; /* The current folio to write to. */
 	unsigned long tot_in = 0;
 	unsigned long tot_out = 0;
 	unsigned long len = *total_out;
-	const unsigned long nr_dest_pages = *out_pages;
-	unsigned long max_out = nr_dest_pages * PAGE_SIZE;
+	const unsigned long nr_dest_folios = *out_folios;
+	unsigned long max_out = nr_dest_folios * PAGE_SIZE;
 	zstd_parameters params = zstd_get_btrfs_parameters(workspace->req_level,
 							   len);
 
-	*out_pages = 0;
+	*out_folios = 0;
 	*total_out = 0;
 	*total_in = 0;
 
@@ -405,20 +406,21 @@ int zstd_compress_pages(struct list_head *ws, struct address_space *mapping,
 	}
 
 	/* map in the first page of input data */
-	in_page = find_get_page(mapping, start >> PAGE_SHIFT);
-	workspace->in_buf.src = kmap_local_page(in_page);
+	ret = btrfs_compress_filemap_get_folio(mapping, start, &in_folio);
+	if (ret < 0)
+		goto out;
+	workspace->in_buf.src = kmap_local_folio(in_folio, 0);
 	workspace->in_buf.pos = 0;
 	workspace->in_buf.size = min_t(size_t, len, PAGE_SIZE);
 
-
 	/* Allocate and map in the output buffer */
-	out_page = alloc_page(GFP_NOFS);
-	if (out_page == NULL) {
+	out_folio = btrfs_alloc_compr_folio();
+	if (out_folio == NULL) {
 		ret = -ENOMEM;
 		goto out;
 	}
-	pages[nr_pages++] = out_page;
-	workspace->out_buf.dst = page_address(out_page);
+	folios[nr_folios++] = out_folio;
+	workspace->out_buf.dst = folio_address(out_folio);
 	workspace->out_buf.pos = 0;
 	workspace->out_buf.size = min_t(size_t, max_out, PAGE_SIZE);
 
@@ -453,17 +455,17 @@ int zstd_compress_pages(struct list_head *ws, struct address_space *mapping,
 		if (workspace->out_buf.pos == workspace->out_buf.size) {
 			tot_out += PAGE_SIZE;
 			max_out -= PAGE_SIZE;
-			if (nr_pages == nr_dest_pages) {
+			if (nr_folios == nr_dest_folios) {
 				ret = -E2BIG;
 				goto out;
 			}
-			out_page = alloc_page(GFP_NOFS);
-			if (out_page == NULL) {
+			out_folio = btrfs_alloc_compr_folio();
+			if (out_folio == NULL) {
 				ret = -ENOMEM;
 				goto out;
 			}
-			pages[nr_pages++] = out_page;
-			workspace->out_buf.dst = page_address(out_page);
+			folios[nr_folios++] = out_folio;
+			workspace->out_buf.dst = folio_address(out_folio);
 			workspace->out_buf.pos = 0;
 			workspace->out_buf.size = min_t(size_t, max_out,
 							PAGE_SIZE);
@@ -479,11 +481,14 @@ int zstd_compress_pages(struct list_head *ws, struct address_space *mapping,
 		if (workspace->in_buf.pos == workspace->in_buf.size) {
 			tot_in += PAGE_SIZE;
 			kunmap_local(workspace->in_buf.src);
-			put_page(in_page);
+			workspace->in_buf.src = NULL;
+			folio_put(in_folio);
 			start += PAGE_SIZE;
 			len -= PAGE_SIZE;
-			in_page = find_get_page(mapping, start >> PAGE_SHIFT);
-			workspace->in_buf.src = kmap_local_page(in_page);
+			ret = btrfs_compress_filemap_get_folio(mapping, start, &in_folio);
+			if (ret < 0)
+				goto out;
+			workspace->in_buf.src = kmap_local_folio(in_folio, 0);
 			workspace->in_buf.pos = 0;
 			workspace->in_buf.size = min_t(size_t, len, PAGE_SIZE);
 		}
@@ -510,17 +515,17 @@ int zstd_compress_pages(struct list_head *ws, struct address_space *mapping,
 
 		tot_out += PAGE_SIZE;
 		max_out -= PAGE_SIZE;
-		if (nr_pages == nr_dest_pages) {
+		if (nr_folios == nr_dest_folios) {
 			ret = -E2BIG;
 			goto out;
 		}
-		out_page = alloc_page(GFP_NOFS);
-		if (out_page == NULL) {
+		out_folio = btrfs_alloc_compr_folio();
+		if (out_folio == NULL) {
 			ret = -ENOMEM;
 			goto out;
 		}
-		pages[nr_pages++] = out_page;
-		workspace->out_buf.dst = page_address(out_page);
+		folios[nr_folios++] = out_folio;
+		workspace->out_buf.dst = folio_address(out_folio);
 		workspace->out_buf.pos = 0;
 		workspace->out_buf.size = min_t(size_t, max_out, PAGE_SIZE);
 	}
@@ -534,10 +539,10 @@ int zstd_compress_pages(struct list_head *ws, struct address_space *mapping,
 	*total_in = tot_in;
 	*total_out = tot_out;
 out:
-	*out_pages = nr_pages;
+	*out_folios = nr_folios;
 	if (workspace->in_buf.src) {
 		kunmap_local(workspace->in_buf.src);
-		put_page(in_page);
+		folio_put(in_folio);
 	}
 	return ret;
 }
@@ -545,12 +550,12 @@ out:
 int zstd_decompress_bio(struct list_head *ws, struct compressed_bio *cb)
 {
 	struct workspace *workspace = list_entry(ws, struct workspace, list);
-	struct page **pages_in = cb->compressed_pages;
+	struct folio **folios_in = cb->compressed_folios;
 	size_t srclen = cb->compressed_len;
 	zstd_dstream *stream;
 	int ret = 0;
-	unsigned long page_in_index = 0;
-	unsigned long total_pages_in = DIV_ROUND_UP(srclen, PAGE_SIZE);
+	unsigned long folio_in_index = 0;
+	unsigned long total_folios_in = DIV_ROUND_UP(srclen, PAGE_SIZE);
 	unsigned long buf_start;
 	unsigned long total_out = 0;
 
@@ -562,7 +567,7 @@ int zstd_decompress_bio(struct list_head *ws, struct compressed_bio *cb)
 		goto done;
 	}
 
-	workspace->in_buf.src = kmap_local_page(pages_in[page_in_index]);
+	workspace->in_buf.src = kmap_local_folio(folios_in[folio_in_index], 0);
 	workspace->in_buf.pos = 0;
 	workspace->in_buf.size = min_t(size_t, srclen, PAGE_SIZE);
 
@@ -599,14 +604,15 @@ int zstd_decompress_bio(struct list_head *ws, struct compressed_bio *cb)
 
 		if (workspace->in_buf.pos == workspace->in_buf.size) {
 			kunmap_local(workspace->in_buf.src);
-			page_in_index++;
-			if (page_in_index >= total_pages_in) {
+			folio_in_index++;
+			if (folio_in_index >= total_folios_in) {
 				workspace->in_buf.src = NULL;
 				ret = -EIO;
 				goto done;
 			}
 			srclen -= PAGE_SIZE;
-			workspace->in_buf.src = kmap_local_page(pages_in[page_in_index]);
+			workspace->in_buf.src =
+				kmap_local_folio(folios_in[folio_in_index], 0);
 			workspace->in_buf.pos = 0;
 			workspace->in_buf.size = min_t(size_t, srclen, PAGE_SIZE);
 		}
@@ -619,80 +625,48 @@ done:
 }
 
 int zstd_decompress(struct list_head *ws, const u8 *data_in,
-		struct page *dest_page, unsigned long start_byte, size_t srclen,
+		struct page *dest_page, unsigned long dest_pgoff, size_t srclen,
 		size_t destlen)
 {
 	struct workspace *workspace = list_entry(ws, struct workspace, list);
+	struct btrfs_fs_info *fs_info = btrfs_sb(dest_page->mapping->host->i_sb);
+	const u32 sectorsize = fs_info->sectorsize;
 	zstd_dstream *stream;
 	int ret = 0;
-	size_t ret2;
-	unsigned long total_out = 0;
-	unsigned long pg_offset = 0;
+	unsigned long to_copy = 0;
 
 	stream = zstd_init_dstream(
 			ZSTD_BTRFS_MAX_INPUT, workspace->mem, workspace->size);
 	if (!stream) {
 		pr_warn("BTRFS: zstd_init_dstream failed\n");
-		ret = -EIO;
 		goto finish;
 	}
 
-	destlen = min_t(size_t, destlen, PAGE_SIZE);
-
 	workspace->in_buf.src = data_in;
 	workspace->in_buf.pos = 0;
 	workspace->in_buf.size = srclen;
 
 	workspace->out_buf.dst = workspace->buf;
 	workspace->out_buf.pos = 0;
-	workspace->out_buf.size = PAGE_SIZE;
-
-	ret2 = 1;
-	while (pg_offset < destlen
-	       && workspace->in_buf.pos < workspace->in_buf.size) {
-		unsigned long buf_start;
-		unsigned long buf_offset;
-		unsigned long bytes;
-
-		/* Check if the frame is over and we still need more input */
-		if (ret2 == 0) {
-			pr_debug("BTRFS: zstd_decompress_stream ended early\n");
-			ret = -EIO;
-			goto finish;
-		}
-		ret2 = zstd_decompress_stream(stream, &workspace->out_buf,
-				&workspace->in_buf);
-		if (zstd_is_error(ret2)) {
-			pr_debug("BTRFS: zstd_decompress_stream returned %d\n",
-					zstd_get_error_code(ret2));
-			ret = -EIO;
-			goto finish;
-		}
-
-		buf_start = total_out;
-		total_out += workspace->out_buf.pos;
-		workspace->out_buf.pos = 0;
-
-		if (total_out <= start_byte)
-			continue;
-
-		if (total_out > start_byte && buf_start < start_byte)
-			buf_offset = start_byte - buf_start;
-		else
-			buf_offset = 0;
-
-		bytes = min_t(unsigned long, destlen - pg_offset,
-				workspace->out_buf.size - buf_offset);
-
-		memcpy_to_page(dest_page, pg_offset,
-			       workspace->out_buf.dst + buf_offset, bytes);
-
-		pg_offset += bytes;
+	workspace->out_buf.size = sectorsize;
+
+	/*
+	 * Since both input and output buffers should not exceed one sector,
+	 * one call should end the decompression.
+	 */
+	ret = zstd_decompress_stream(stream, &workspace->out_buf, &workspace->in_buf);
+	if (zstd_is_error(ret)) {
+		pr_warn_ratelimited("BTRFS: zstd_decompress_stream return %d\n",
+				    zstd_get_error_code(ret));
+		goto finish;
 	}
-	ret = 0;
+	to_copy = workspace->out_buf.pos;
+	memcpy_to_page(dest_page, dest_pgoff, workspace->out_buf.dst, to_copy);
 finish:
-	if (pg_offset < destlen) {
-		memzero_page(dest_page, pg_offset, destlen - pg_offset);
+	/* Error or early end. */
+	if (unlikely(to_copy < destlen)) {
+		ret = -EIO;
+		memzero_page(dest_page, dest_pgoff + to_copy, destlen - to_copy);
 	}
 	return ret;
 }