diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 2c858d5349c80e6f683bdc52ddaddf759b3d798b..45899abb53dbf30a6dd93a257c736294bb539dee 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -585,6 +585,12 @@ enum {
/* Indicate whether there are any tree modification log users */
BTRFS_FS_TREE_MOD_LOG_USERS,
+
+#if BITS_PER_LONG == 32
+ /* Indicate if we have error/warn message printed on 32bit systems */
+ BTRFS_FS_32BIT_ERROR,
+ BTRFS_FS_32BIT_WARN,
+#endif
};
/*
@@ -3412,6 +3418,19 @@ static inline void assertfail(const char *expr, const char* file, int line) { }
#define ASSERT(expr) (void)(expr)
#endif
+#if BITS_PER_LONG == 32
+#define BTRFS_32BIT_MAX_FILE_SIZE (((u64)ULONG_MAX + 1) << PAGE_SHIFT)
+/*
+ * The warning threshold is 5/8th of the MAX_LFS_FILESIZE that limits the logical
+ * addresses of extents.
+ *
+ * For 4K page size it's about 10T, for 64K it's 160T.
+ */
+#define BTRFS_32BIT_EARLY_WARN_THRESHOLD (BTRFS_32BIT_MAX_FILE_SIZE * 5 / 8)
+void btrfs_warn_32bit_limit(struct btrfs_fs_info *fs_info);
+void btrfs_err_32bit_limit(struct btrfs_fs_info *fs_info);
+#endif
+
/*
* Get the correct offset inside the page of extent buffer.
*
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index b1599d8fcbd73194074809958afe4eb6610f0b9e..f2d1bb2343779fa3998792f76477dfe3b7281588 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -5821,6 +5821,17 @@ struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info,
return ERR_PTR(-EINVAL);
}
+#if BITS_PER_LONG == 32
+ if (start >= MAX_LFS_FILESIZE) {
+ btrfs_err_rl(fs_info,
+ "extent buffer %llu is beyond 32bit page cache limit", start);
+ btrfs_err_32bit_limit(fs_info);
+ return ERR_PTR(-EOVERFLOW);
+ }
+ if (start >= BTRFS_32BIT_EARLY_WARN_THRESHOLD)
+ btrfs_warn_32bit_limit(fs_info);
+#endif
+
if (fs_info->sectorsize < PAGE_SIZE &&
offset_in_page(start) + len > PAGE_SIZE) {
btrfs_err(fs_info,
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index f7a4ad86adee61610c686f7321d23f5676a983e3..4a396c1147f177c159909390806a153f22fe9f55 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -252,6 +252,32 @@ void __cold btrfs_printk(const struct btrfs_fs_info *fs_info, const char *fmt, .
}
#endif
+#if BITS_PER_LONG == 32
+void __cold btrfs_warn_32bit_limit(struct btrfs_fs_info *fs_info)
+{
+ if (!test_and_set_bit(BTRFS_FS_32BIT_WARN, &fs_info->flags)) {
+ btrfs_warn(fs_info, "reaching 32bit limit for logical addresses");
+ btrfs_warn(fs_info,
+"due to page cache limit on 32bit systems, btrfs can't access metadata at or beyond %lluT",
+ BTRFS_32BIT_MAX_FILE_SIZE >> 40);
+ btrfs_warn(fs_info,
+ "please consider upgrading to 64bit kernel/hardware");
+ }
+}
+
+void __cold btrfs_err_32bit_limit(struct btrfs_fs_info *fs_info)
+{
+ if (!test_and_set_bit(BTRFS_FS_32BIT_ERROR, &fs_info->flags)) {
+ btrfs_err(fs_info, "reached 32bit limit for logical addresses");
+ btrfs_err(fs_info,
+"due to page cache limit on 32bit systems, metadata beyond %lluT can't be accessed",
+ BTRFS_32BIT_MAX_FILE_SIZE >> 40);
+ btrfs_err(fs_info,
+ "please consider upgrading to 64bit kernel/hardware");
+ }
+}
+#endif
+
/*
* We only mark the transaction aborted and then set the file system read-only.
* This will prevent new transactions from starting or trying to join this
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 6d9b2369f17a564d27cdf3e75c4dfb617a22133f..517b40439235c68a8f766341ca5412082bddda45 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -6789,6 +6789,46 @@ static u64 calc_stripe_length(u64 type, u64 chunk_len, int num_stripes)
return div_u64(chunk_len, data_stripes);
}
+#if BITS_PER_LONG == 32
+/*
+ * Due to page cache limit, metadata beyond BTRFS_32BIT_MAX_FILE_SIZE
+ * can't be accessed on 32bit systems.
+ *
+ * This function do mount time check to reject the fs if it already has
+ * metadata chunk beyond that limit.
+ */
+static int check_32bit_meta_chunk(struct btrfs_fs_info *fs_info,
+ u64 logical, u64 length, u64 type)
+{
+ if (!(type & BTRFS_BLOCK_GROUP_METADATA))
+ return 0;
+
+ if (logical + length < MAX_LFS_FILESIZE)
+ return 0;
+
+ btrfs_err_32bit_limit(fs_info);
+ return -EOVERFLOW;
+}
+
+/*
+ * This is to give early warning for any metadata chunk reaching
+ * BTRFS_32BIT_EARLY_WARN_THRESHOLD.
+ * Although we can still access the metadata, it's not going to be possible
+ * once the limit is reached.
+ */
+static void warn_32bit_meta_chunk(struct btrfs_fs_info *fs_info,
+ u64 logical, u64 length, u64 type)
+{
+ if (!(type & BTRFS_BLOCK_GROUP_METADATA))
+ return;
+
+ if (logical + length < BTRFS_32BIT_EARLY_WARN_THRESHOLD)
+ return;
+
+ btrfs_warn_32bit_limit(fs_info);
+}
+#endif
+
static int read_one_chunk(struct btrfs_key *key, struct extent_buffer *leaf,
struct btrfs_chunk *chunk)
{
@@ -6799,6 +6839,7 @@ static int read_one_chunk(struct btrfs_key *key, struct extent_buffer *leaf,
u64 logical;
u64 length;
u64 devid;
+ u64 type;
u8 uuid[BTRFS_UUID_SIZE];
int num_stripes;
int ret;
@@ -6806,8 +6847,16 @@ static int read_one_chunk(struct btrfs_key *key, struct extent_buffer *leaf,
logical = key->offset;
length = btrfs_chunk_length(leaf, chunk);
+ type = btrfs_chunk_type(leaf, chunk);
num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
+#if BITS_PER_LONG == 32
+ ret = check_32bit_meta_chunk(fs_info, logical, length, type);
+ if (ret < 0)
+ return ret;
+ warn_32bit_meta_chunk(fs_info, logical, length, type);
+#endif
+
/*
* Only need to verify chunk item if we're reading from sys chunk array,
* as chunk item in tree block is already verified by tree-checker.
@@ -6851,10 +6900,10 @@ static int read_one_chunk(struct btrfs_key *key, struct extent_buffer *leaf,
map->io_width = btrfs_chunk_io_width(leaf, chunk);
map->io_align = btrfs_chunk_io_align(leaf, chunk);
map->stripe_len = btrfs_chunk_stripe_len(leaf, chunk);
- map->type = btrfs_chunk_type(leaf, chunk);
+ map->type = type;
map->sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk);
map->verified_stripes = 0;
- em->orig_block_len = calc_stripe_length(map->type, em->len,
+ em->orig_block_len = calc_stripe_length(type, em->len,
map->num_stripes);
for (i = 0; i < num_stripes; i++) {
map->stripes[i].physical =