Merge branch 'dev' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs.gitNotice: this object is not reachable from any branch.

Notice: this object is not reachable from any branch.

6 files changed, 216 insertions, 191 deletions

diff --git a/fs/erofs/Makefile b/fs/erofs/Makefile
index 994d0b9deddf15..20d1ec42244354 100644
--- a/fs/erofs/Makefile
+++ b/fs/erofs/Makefile
@@ -1,9 +1,9 @@
 # SPDX-License-Identifier: GPL-2.0-only
 
 obj-$(CONFIG_EROFS_FS) += erofs.o
-erofs-objs := super.o inode.o data.o namei.o dir.o utils.o sysfs.o
+erofs-objs := super.o inode.o data.o namei.o dir.o sysfs.o
 erofs-$(CONFIG_EROFS_FS_XATTR) += xattr.o
-erofs-$(CONFIG_EROFS_FS_ZIP) += decompressor.o zmap.o zdata.o pcpubuf.o
+erofs-$(CONFIG_EROFS_FS_ZIP) += decompressor.o zmap.o zdata.o zutil.o
 erofs-$(CONFIG_EROFS_FS_ZIP_LZMA) += decompressor_lzma.o
 erofs-$(CONFIG_EROFS_FS_ZIP_DEFLATE) += decompressor_deflate.o
 erofs-$(CONFIG_EROFS_FS_ONDEMAND) += fscache.o
diff --git a/fs/erofs/decompressor.c b/fs/erofs/decompressor.c
index 2ec9b2bb628d6b..d2fe8130819e14 100644
--- a/fs/erofs/decompressor.c
+++ b/fs/erofs/decompressor.c
@@ -54,7 +54,7 @@ static int z_erofs_load_lz4_config(struct super_block *sb,
 	sbi->lz4.max_distance_pages = distance ?
 					DIV_ROUND_UP(distance, PAGE_SIZE) + 1 :
 					LZ4_MAX_DISTANCE_PAGES;
-	return erofs_pcpubuf_growsize(sbi->lz4.max_pclusterblks);
+	return z_erofs_gbuf_growsize(sbi->lz4.max_pclusterblks);
 }
 
 /*
@@ -111,7 +111,7 @@ static int z_erofs_lz4_prepare_dstpages(struct z_erofs_lz4_decompress_ctx *ctx,
 			victim = availables[--top];
 			get_page(victim);
 		} else {
-			victim = erofs_allocpage(pagepool, rq->gfp);
+			victim = __erofs_allocpage(pagepool, rq->gfp, true);
 			if (!victim)
 				return -ENOMEM;
 			set_page_private(victim, Z_EROFS_SHORTLIVED_PAGE);
@@ -159,7 +159,7 @@ static void *z_erofs_lz4_handle_overlap(struct z_erofs_lz4_decompress_ctx *ctx,
 docopy:
 	/* Or copy compressed data which can be overlapped to per-CPU buffer */
 	in = rq->in;
-	src = erofs_get_pcpubuf(ctx->inpages);
+	src = z_erofs_get_gbuf(ctx->inpages);
 	if (!src) {
 		DBG_BUGON(1);
 		kunmap_local(inpage);
@@ -260,7 +260,7 @@ static int z_erofs_lz4_decompress_mem(struct z_erofs_lz4_decompress_ctx *ctx,
 	} else if (maptype == 1) {
 		vm_unmap_ram(src, ctx->inpages);
 	} else if (maptype == 2) {
-		erofs_put_pcpubuf(src);
+		z_erofs_put_gbuf(src);
 	} else if (maptype != 3) {
 		DBG_BUGON(1);
 		return -EFAULT;
diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h
index d28ccfc0352b1a..53ebba952a2fd0 100644
--- a/fs/erofs/internal.h
+++ b/fs/erofs/internal.h
@@ -438,7 +438,11 @@ void erofs_unregister_sysfs(struct super_block *sb);
 int __init erofs_init_sysfs(void);
 void erofs_exit_sysfs(void);
 
-struct page *erofs_allocpage(struct page **pagepool, gfp_t gfp);
+struct page *__erofs_allocpage(struct page **pagepool, gfp_t gfp, bool tryrsv);
+static inline struct page *erofs_allocpage(struct page **pagepool, gfp_t gfp)
+{
+	return __erofs_allocpage(pagepool, gfp, false);
+}
 static inline void erofs_pagepool_add(struct page **pagepool, struct page *page)
 {
 	set_page_private(page, (unsigned long)*pagepool);
@@ -463,11 +467,11 @@ int erofs_try_to_free_all_cached_folios(struct erofs_sb_info *sbi,
 					struct erofs_workgroup *egrp);
 int z_erofs_map_blocks_iter(struct inode *inode, struct erofs_map_blocks *map,
 			    int flags);
-void *erofs_get_pcpubuf(unsigned int requiredpages);
-void erofs_put_pcpubuf(void *ptr);
-int erofs_pcpubuf_growsize(unsigned int nrpages);
-void __init erofs_pcpubuf_init(void);
-void erofs_pcpubuf_exit(void);
+void *z_erofs_get_gbuf(unsigned int requiredpages);
+void z_erofs_put_gbuf(void *ptr);
+int z_erofs_gbuf_growsize(unsigned int nrpages);
+int __init z_erofs_gbuf_init(void);
+void z_erofs_gbuf_exit(void);
 int erofs_init_managed_cache(struct super_block *sb);
 int z_erofs_parse_cfgs(struct super_block *sb, struct erofs_super_block *dsb);
 #else
@@ -477,8 +481,8 @@ static inline int erofs_init_shrinker(void) { return 0; }
 static inline void erofs_exit_shrinker(void) {}
 static inline int z_erofs_init_zip_subsystem(void) { return 0; }
 static inline void z_erofs_exit_zip_subsystem(void) {}
-static inline void erofs_pcpubuf_init(void) {}
-static inline void erofs_pcpubuf_exit(void) {}
+static inline int z_erofs_gbuf_init(void) { return 0; }
+static inline void z_erofs_gbuf_exit(void) {}
 static inline int erofs_init_managed_cache(struct super_block *sb) { return 0; }
 #endif	/* !CONFIG_EROFS_FS_ZIP */
 
diff --git a/fs/erofs/pcpubuf.c b/fs/erofs/pcpubuf.c
deleted file mode 100644
index c7a4b1d77069d9..00000000000000
--- a/fs/erofs/pcpubuf.c
+++ /dev/null
@@ -1,148 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * Copyright (C) Gao Xiang <xiang@kernel.org>
- *
- * For low-latency decompression algorithms (e.g. lz4), reserve consecutive
- * per-CPU virtual memory (in pages) in advance to store such inplace I/O
- * data if inplace decompression is failed (due to unmet inplace margin for
- * example).
- */
-#include "internal.h"
-
-struct erofs_pcpubuf {
-	raw_spinlock_t lock;
-	void *ptr;
-	struct page **pages;
-	unsigned int nrpages;
-};
-
-static DEFINE_PER_CPU(struct erofs_pcpubuf, erofs_pcb);
-
-void *erofs_get_pcpubuf(unsigned int requiredpages)
-	__acquires(pcb->lock)
-{
-	struct erofs_pcpubuf *pcb = &get_cpu_var(erofs_pcb);
-
-	raw_spin_lock(&pcb->lock);
-	/* check if the per-CPU buffer is too small */
-	if (requiredpages > pcb->nrpages) {
-		raw_spin_unlock(&pcb->lock);
-		put_cpu_var(erofs_pcb);
-		/* (for sparse checker) pretend pcb->lock is still taken */
-		__acquire(pcb->lock);
-		return NULL;
-	}
-	return pcb->ptr;
-}
-
-void erofs_put_pcpubuf(void *ptr) __releases(pcb->lock)
-{
-	struct erofs_pcpubuf *pcb = &per_cpu(erofs_pcb, smp_processor_id());
-
-	DBG_BUGON(pcb->ptr != ptr);
-	raw_spin_unlock(&pcb->lock);
-	put_cpu_var(erofs_pcb);
-}
-
-/* the next step: support per-CPU page buffers hotplug */
-int erofs_pcpubuf_growsize(unsigned int nrpages)
-{
-	static DEFINE_MUTEX(pcb_resize_mutex);
-	static unsigned int pcb_nrpages;
-	struct page *pagepool = NULL;
-	int delta, cpu, ret, i;
-
-	mutex_lock(&pcb_resize_mutex);
-	delta = nrpages - pcb_nrpages;
-	ret = 0;
-	/* avoid shrinking pcpubuf, since no idea how many fses rely on */
-	if (delta <= 0)
-		goto out;
-
-	for_each_possible_cpu(cpu) {
-		struct erofs_pcpubuf *pcb = &per_cpu(erofs_pcb, cpu);
-		struct page **pages, **oldpages;
-		void *ptr, *old_ptr;
-
-		pages = kmalloc_array(nrpages, sizeof(*pages), GFP_KERNEL);
-		if (!pages) {
-			ret = -ENOMEM;
-			break;
-		}
-
-		for (i = 0; i < nrpages; ++i) {
-			pages[i] = erofs_allocpage(&pagepool, GFP_KERNEL);
-			if (!pages[i]) {
-				ret = -ENOMEM;
-				oldpages = pages;
-				goto free_pagearray;
-			}
-		}
-		ptr = vmap(pages, nrpages, VM_MAP, PAGE_KERNEL);
-		if (!ptr) {
-			ret = -ENOMEM;
-			oldpages = pages;
-			goto free_pagearray;
-		}
-		raw_spin_lock(&pcb->lock);
-		old_ptr = pcb->ptr;
-		pcb->ptr = ptr;
-		oldpages = pcb->pages;
-		pcb->pages = pages;
-		i = pcb->nrpages;
-		pcb->nrpages = nrpages;
-		raw_spin_unlock(&pcb->lock);
-
-		if (!oldpages) {
-			DBG_BUGON(old_ptr);
-			continue;
-		}
-
-		if (old_ptr)
-			vunmap(old_ptr);
-free_pagearray:
-		while (i)
-			erofs_pagepool_add(&pagepool, oldpages[--i]);
-		kfree(oldpages);
-		if (ret)
-			break;
-	}
-	pcb_nrpages = nrpages;
-	erofs_release_pages(&pagepool);
-out:
-	mutex_unlock(&pcb_resize_mutex);
-	return ret;
-}
-
-void __init erofs_pcpubuf_init(void)
-{
-	int cpu;
-
-	for_each_possible_cpu(cpu) {
-		struct erofs_pcpubuf *pcb = &per_cpu(erofs_pcb, cpu);
-
-		raw_spin_lock_init(&pcb->lock);
-	}
-}
-
-void erofs_pcpubuf_exit(void)
-{
-	int cpu, i;
-
-	for_each_possible_cpu(cpu) {
-		struct erofs_pcpubuf *pcb = &per_cpu(erofs_pcb, cpu);
-
-		if (pcb->ptr) {
-			vunmap(pcb->ptr);
-			pcb->ptr = NULL;
-		}
-		if (!pcb->pages)
-			continue;
-
-		for (i = 0; i < pcb->nrpages; ++i)
-			if (pcb->pages[i])
-				put_page(pcb->pages[i]);
-		kfree(pcb->pages);
-		pcb->pages = NULL;
-	}
-}
diff --git a/fs/erofs/super.c b/fs/erofs/super.c
index 30b49b2eee5340..e3438f1a7bacda 100644
--- a/fs/erofs/super.c
+++ b/fs/erofs/super.c
@@ -859,7 +859,10 @@ static int __init erofs_module_init(void)
 	if (err)
 		goto deflate_err;
 
-	erofs_pcpubuf_init();
+	err = z_erofs_gbuf_init();
+	if (err)
+		goto gbuf_err;
+
 	err = z_erofs_init_zip_subsystem();
 	if (err)
 		goto zip_err;
@@ -879,6 +882,8 @@ fs_err:
 sysfs_err:
 	z_erofs_exit_zip_subsystem();
 zip_err:
+	z_erofs_gbuf_exit();
+gbuf_err:
 	z_erofs_deflate_exit();
 deflate_err:
 	z_erofs_lzma_exit();
@@ -902,29 +907,27 @@ static void __exit erofs_module_exit(void)
 	z_erofs_lzma_exit();
 	erofs_exit_shrinker();
 	kmem_cache_destroy(erofs_inode_cachep);
-	erofs_pcpubuf_exit();
+	z_erofs_gbuf_exit();
 }
 
 static int erofs_statfs(struct dentry *dentry, struct kstatfs *buf)
 {
 	struct super_block *sb = dentry->d_sb;
 	struct erofs_sb_info *sbi = EROFS_SB(sb);
-	u64 id = 0;
-
-	if (!erofs_is_fscache_mode(sb))
-		id = huge_encode_dev(sb->s_bdev->bd_dev);
 
 	buf->f_type = sb->s_magic;
 	buf->f_bsize = sb->s_blocksize;
 	buf->f_blocks = sbi->total_blocks;
 	buf->f_bfree = buf->f_bavail = 0;
-
 	buf->f_files = ULLONG_MAX;
 	buf->f_ffree = ULLONG_MAX - sbi->inos;
-
 	buf->f_namelen = EROFS_NAME_LEN;
 
-	buf->f_fsid    = u64_to_fsid(id);
+	if (uuid_is_null(&sb->s_uuid))
+		buf->f_fsid = u64_to_fsid(erofs_is_fscache_mode(sb) ? 0 :
+				huge_encode_dev(sb->s_bdev->bd_dev));
+	else
+		buf->f_fsid = uuid_to_fsid(sb->s_uuid.b);
 	return 0;
 }
 
diff --git a/fs/erofs/utils.c b/fs/erofs/zutil.c
index 518bdd69c82325..036024bce9f7fd 100644
--- a/fs/erofs/utils.c
+++ b/fs/erofs/zutil.c
@@ -5,16 +5,186 @@
  */
 #include "internal.h"
 
-struct page *erofs_allocpage(struct page **pagepool, gfp_t gfp)
+struct z_erofs_gbuf {
+	spinlock_t lock;
+	void *ptr;
+	struct page **pages;
+	unsigned int nrpages;
+};
+
+static struct z_erofs_gbuf *z_erofs_gbufpool, *z_erofs_rsvbuf;
+static unsigned int z_erofs_gbuf_count, z_erofs_gbuf_nrpages,
+		z_erofs_rsv_nrpages;
+
+module_param_named(global_buffers, z_erofs_gbuf_count, uint, 0444);
+module_param_named(reserved_pages, z_erofs_rsv_nrpages, uint, 0444);
+
+static atomic_long_t erofs_global_shrink_cnt;	/* for all mounted instances */
+/* protected by 'erofs_sb_list_lock' */
+static unsigned int shrinker_run_no;
+
+/* protects the mounted 'erofs_sb_list' */
+static DEFINE_SPINLOCK(erofs_sb_list_lock);
+static LIST_HEAD(erofs_sb_list);
+static struct shrinker *erofs_shrinker_info;
+
+static unsigned int z_erofs_gbuf_id(void)
+{
+	return raw_smp_processor_id() % z_erofs_gbuf_count;
+}
+
+void *z_erofs_get_gbuf(unsigned int requiredpages)
+	__acquires(gbuf->lock)
+{
+	struct z_erofs_gbuf *gbuf;
+
+	gbuf = &z_erofs_gbufpool[z_erofs_gbuf_id()];
+	spin_lock(&gbuf->lock);
+	/* check if the buffer is too small */
+	if (requiredpages > gbuf->nrpages) {
+		spin_unlock(&gbuf->lock);
+		/* (for sparse checker) pretend gbuf->lock is still taken */
+		__acquire(gbuf->lock);
+		return NULL;
+	}
+	return gbuf->ptr;
+}
+
+void z_erofs_put_gbuf(void *ptr) __releases(gbuf->lock)
+{
+	struct z_erofs_gbuf *gbuf;
+
+	gbuf = &z_erofs_gbufpool[z_erofs_gbuf_id()];
+	DBG_BUGON(gbuf->ptr != ptr);
+	spin_unlock(&gbuf->lock);
+}
+
+int z_erofs_gbuf_growsize(unsigned int nrpages)
+{
+	static DEFINE_MUTEX(gbuf_resize_mutex);
+	struct page **tmp_pages = NULL;
+	struct z_erofs_gbuf *gbuf;
+	void *ptr, *old_ptr;
+	int last, i, j;
+
+	mutex_lock(&gbuf_resize_mutex);
+	/* avoid shrinking gbufs, since no idea how many fses rely on */
+	if (nrpages <= z_erofs_gbuf_nrpages) {
+		mutex_unlock(&gbuf_resize_mutex);
+		return 0;
+	}
+
+	for (i = 0; i < z_erofs_gbuf_count; ++i) {
+		gbuf = &z_erofs_gbufpool[i];
+		tmp_pages = kcalloc(nrpages, sizeof(*tmp_pages), GFP_KERNEL);
+		if (!tmp_pages)
+			goto out;
+
+		for (j = 0; j < gbuf->nrpages; ++j)
+			tmp_pages[j] = gbuf->pages[j];
+		do {
+			last = j;
+			j = alloc_pages_bulk_array(GFP_KERNEL, nrpages,
+						   tmp_pages);
+			if (last == j)
+				goto out;
+		} while (j != nrpages);
+
+		ptr = vmap(tmp_pages, nrpages, VM_MAP, PAGE_KERNEL);
+		if (!ptr)
+			goto out;
+
+		spin_lock(&gbuf->lock);
+		kfree(gbuf->pages);
+		gbuf->pages = tmp_pages;
+		old_ptr = gbuf->ptr;
+		gbuf->ptr = ptr;
+		gbuf->nrpages = nrpages;
+		spin_unlock(&gbuf->lock);
+		if (old_ptr)
+			vunmap(old_ptr);
+	}
+	z_erofs_gbuf_nrpages = nrpages;
+out:
+	if (i < z_erofs_gbuf_count && tmp_pages) {
+		for (j = 0; j < nrpages; ++j)
+			if (tmp_pages[j] && tmp_pages[j] != gbuf->pages[j])
+				__free_page(tmp_pages[j]);
+		kfree(tmp_pages);
+	}
+	mutex_unlock(&gbuf_resize_mutex);
+	return i < z_erofs_gbuf_count ? -ENOMEM : 0;
+}
+
+int __init z_erofs_gbuf_init(void)
+{
+	unsigned int i, total = num_possible_cpus();
+
+	if (z_erofs_gbuf_count)
+		total = min(z_erofs_gbuf_count, total);
+	z_erofs_gbuf_count = total;
+
+	/* The last (special) global buffer is the reserved buffer */
+	total += !!z_erofs_rsv_nrpages;
+
+	z_erofs_gbufpool = kcalloc(total, sizeof(*z_erofs_gbufpool),
+				   GFP_KERNEL);
+	if (!z_erofs_gbufpool)
+		return -ENOMEM;
+
+	if (z_erofs_rsv_nrpages) {
+		z_erofs_rsvbuf = &z_erofs_gbufpool[total - 1];
+		z_erofs_rsvbuf->pages = kcalloc(z_erofs_rsv_nrpages,
+				sizeof(*z_erofs_rsvbuf->pages), GFP_KERNEL);
+		if (!z_erofs_rsvbuf->pages) {
+			z_erofs_rsvbuf = NULL;
+			z_erofs_rsv_nrpages = 0;
+		}
+	}
+	for (i = 0; i < total; ++i)
+		spin_lock_init(&z_erofs_gbufpool[i].lock);
+	return 0;
+}
+
+void z_erofs_gbuf_exit(void)
+{
+	int i;
+
+	for (i = 0; i < z_erofs_gbuf_count + (!!z_erofs_rsvbuf); ++i) {
+		struct z_erofs_gbuf *gbuf = &z_erofs_gbufpool[i];
+
+		if (gbuf->ptr) {
+			vunmap(gbuf->ptr);
+			gbuf->ptr = NULL;
+		}
+
+		if (!gbuf->pages)
+			continue;
+
+		for (i = 0; i < gbuf->nrpages; ++i)
+			if (gbuf->pages[i])
+				put_page(gbuf->pages[i]);
+		kfree(gbuf->pages);
+		gbuf->pages = NULL;
+	}
+	kfree(z_erofs_gbufpool);
+}
+
+struct page *__erofs_allocpage(struct page **pagepool, gfp_t gfp, bool tryrsv)
 {
 	struct page *page = *pagepool;
 
 	if (page) {
-		DBG_BUGON(page_ref_count(page) != 1);
 		*pagepool = (struct page *)page_private(page);
-	} else {
-		page = alloc_page(gfp);
+	} else if (tryrsv && z_erofs_rsvbuf && z_erofs_rsvbuf->nrpages) {
+		spin_lock(&z_erofs_rsvbuf->lock);
+		if (z_erofs_rsvbuf->nrpages)
+			page = z_erofs_rsvbuf->pages[--z_erofs_rsvbuf->nrpages];
+		spin_unlock(&z_erofs_rsvbuf->lock);
 	}
+	if (!page)
+		page = alloc_page(gfp);
+	DBG_BUGON(page && page_ref_count(page) != 1);
 	return page;
 }
 
@@ -24,14 +194,22 @@ void erofs_release_pages(struct page **pagepool)
 		struct page *page = *pagepool;
 
 		*pagepool = (struct page *)page_private(page);
+		/* try to fill reserved global pool first */
+		if (z_erofs_rsvbuf && z_erofs_rsvbuf->nrpages <
+				z_erofs_rsv_nrpages) {
+			spin_lock(&z_erofs_rsvbuf->lock);
+			if (z_erofs_rsvbuf->nrpages < z_erofs_rsv_nrpages) {
+				z_erofs_rsvbuf->pages[z_erofs_rsvbuf->nrpages++]
+						= page;
+				spin_unlock(&z_erofs_rsvbuf->lock);
+				continue;
+			}
+			spin_unlock(&z_erofs_rsvbuf->lock);
+		}
 		put_page(page);
 	}
 }
 
-#ifdef CONFIG_EROFS_FS_ZIP
-/* global shrink count (for all mounted EROFS instances) */
-static atomic_long_t erofs_global_shrink_cnt;
-
 static bool erofs_workgroup_get(struct erofs_workgroup *grp)
 {
 	if (lockref_get_not_zero(&grp->lockref))
@@ -171,13 +349,6 @@ static unsigned long erofs_shrink_workstation(struct erofs_sb_info *sbi,
 	return freed;
 }
 
-/* protected by 'erofs_sb_list_lock' */
-static unsigned int shrinker_run_no;
-
-/* protects the mounted 'erofs_sb_list' */
-static DEFINE_SPINLOCK(erofs_sb_list_lock);
-static LIST_HEAD(erofs_sb_list);
-
 void erofs_shrinker_register(struct super_block *sb)
 {
 	struct erofs_sb_info *sbi = EROFS_SB(sb);
@@ -264,8 +435,6 @@ static unsigned long erofs_shrink_scan(struct shrinker *shrink,
 	return freed;
 }
 
-static struct shrinker *erofs_shrinker_info;
-
 int __init erofs_init_shrinker(void)
 {
 	erofs_shrinker_info = shrinker_alloc(0, "erofs-shrinker");
@@ -274,9 +443,7 @@ int __init erofs_init_shrinker(void)
 
 	erofs_shrinker_info->count_objects = erofs_shrink_count;
 	erofs_shrinker_info->scan_objects = erofs_shrink_scan;
-
 	shrinker_register(erofs_shrinker_info);
-
 	return 0;
 }
 
@@ -284,4 +451,3 @@ void erofs_exit_shrinker(void)
 {
 	shrinker_free(erofs_shrinker_info);
 }
-#endif	/* !CONFIG_EROFS_FS_ZIP */