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Message-Id: <20170715003849.1982-1-tahsin@google.com>
Date: Fri, 14 Jul 2017 17:38:49 -0700
From: Tahsin Erdogan <tahsin@...gle.com>
To: Theodore Ts'o <tytso@....edu>, Andreas Dilger <adilger@...ger.ca>,
linux-ext4@...r.kernel.org
Cc: Tahsin Erdogan <tahsin@...gle.com>
Subject: [PATCH] resize2fs: add support for resizing filesystems with ea_inode feature
Resizing filesystems with ea_inode feature was disallowed so far
because the code for updating the ea entries was missing. This patch
adds that support.
Signed-off-by: Tahsin Erdogan <tahsin@...gle.com>
---
lib/ext2fs/ext2_err.et.in | 3 -
resize/resize2fs.c | 167 +++++++++++++++++++++++++++++++++++++++++++---
2 files changed, 157 insertions(+), 13 deletions(-)
diff --git a/lib/ext2fs/ext2_err.et.in b/lib/ext2fs/ext2_err.et.in
index c5a9ffcc420c..ac96964d93d0 100644
--- a/lib/ext2fs/ext2_err.et.in
+++ b/lib/ext2fs/ext2_err.et.in
@@ -542,7 +542,4 @@ ec EXT2_ET_CORRUPT_JOURNAL_SB,
ec EXT2_ET_INODE_CORRUPTED,
"Inode is corrupted"
-ec EXT2_ET_CANNOT_MOVE_EA_INODE,
- "Cannot move extended attribute inode"
-
end
diff --git a/resize/resize2fs.c b/resize/resize2fs.c
index a54564f08ae5..20a0c463e411 100644
--- a/resize/resize2fs.c
+++ b/resize/resize2fs.c
@@ -1986,6 +1986,145 @@ static void quiet_com_err_proc(const char *whoami EXT2FS_ATTR((unused)),
{
}
+static int fix_ea_entries(ext2_extent imap, struct ext2_ext_attr_entry *entry,
+ struct ext2_ext_attr_entry *end, ext2_ino_t last_ino)
+{
+ int modified = 0;
+ ext2_ino_t new_ino;
+ errcode_t retval;
+
+ while (entry < end && !EXT2_EXT_IS_LAST_ENTRY(entry)) {
+ if (entry->e_value_inum > last_ino) {
+ new_ino = ext2fs_extent_translate(imap,
+ entry->e_value_inum);
+ entry->e_value_inum = new_ino;
+ modified = 1;
+ }
+ entry = EXT2_EXT_ATTR_NEXT(entry);
+ }
+ return modified;
+}
+
+static int fix_ea_ibody_entries(ext2_extent imap,
+ struct ext2_inode_large *inode, int inode_size,
+ ext2_ino_t last_ino)
+{
+ struct ext2_ext_attr_entry *start, *end;
+ __u32 *ea_magic;
+
+ if (inode->i_extra_isize == 0)
+ return 0;
+
+ ea_magic = (__u32 *)((char *)inode + EXT2_GOOD_OLD_INODE_SIZE +
+ inode->i_extra_isize);
+ if (*ea_magic != EXT2_EXT_ATTR_MAGIC)
+ return 0;
+
+ start = (struct ext2_ext_attr_entry *)(ea_magic + 1);
+ end = (struct ext2_ext_attr_entry *)((char *)inode + inode_size);
+
+ return fix_ea_entries(imap, start, end, last_ino);
+}
+
+static int fix_ea_block_entries(ext2_extent imap, char *block_buf,
+ unsigned int blocksize, ext2_ino_t last_ino)
+{
+ struct ext2_ext_attr_header *header;
+ struct ext2_ext_attr_entry *start, *end;
+
+ header = (struct ext2_ext_attr_header *)block_buf;
+ start = (struct ext2_ext_attr_entry *)(header+1);
+ end = (struct ext2_ext_attr_entry *)(block_buf + blocksize);
+
+ return fix_ea_entries(imap, start, end, last_ino);
+}
+
+/* A simple LRU cache to check recently processed blocks. */
+struct blk_cache {
+ int cursor;
+ blk64_t blks[4];
+};
+
+#define BLK_IN_CACHE(b,c) ((b) == (c).blks[0] || (b) == (c).blks[1] || \
+ (b) == (c).blks[2] || (b) == (c).blks[3])
+#define BLK_ADD_CACHE(b,c) { \
+ (c).blks[(c).cursor] = (b); \
+ (c).cursor = ((c).cursor + 1) % 4; \
+}
+
+static errcode_t fix_ea_inode_refs(ext2_resize_t rfs, struct ext2_inode *inode,
+ char *block_buf, ext2_ino_t last_ino)
+{
+ ext2_filsys fs = rfs->new_fs;
+ ext2_inode_scan scan = NULL;
+ ext2_ino_t ino;
+ int inode_size = EXT2_INODE_SIZE(fs->super);
+ blk64_t blk;
+ int modified;
+ struct blk_cache blk_cache = { 0 };
+ struct ext2_ext_attr_header *header;
+ errcode_t retval;
+
+ header = (struct ext2_ext_attr_header *)block_buf;
+
+ retval = ext2fs_open_inode_scan(fs, 0, &scan);
+ if (retval)
+ goto out;
+
+ while (1) {
+ retval = ext2fs_get_next_inode_full(scan, &ino, inode,
+ inode_size);
+ if (retval)
+ goto out;
+ if (!ino)
+ break;
+
+ if (inode->i_links_count == 0 && ino != EXT2_RESIZE_INO)
+ continue; /* inode not in use */
+
+ if (inode_size != EXT2_GOOD_OLD_INODE_SIZE) {
+ modified = fix_ea_ibody_entries(rfs->imap,
+ (struct ext2_inode_large *)inode,
+ inode_size, last_ino);
+ if (modified) {
+ retval = ext2fs_write_inode_full(fs, ino, inode,
+ inode_size);
+ if (retval)
+ goto out;
+ }
+ }
+
+ blk = ext2fs_file_acl_block(fs, inode);
+ if (blk && !BLK_IN_CACHE(blk, blk_cache)) {
+ retval = ext2fs_read_ext_attr3(fs, blk, block_buf, ino);
+ if (retval)
+ goto out;
+
+ modified = fix_ea_block_entries(rfs->imap, block_buf,
+ fs->blocksize,
+ last_ino);
+ if (modified) {
+ retval = ext2fs_write_ext_attr3(fs, blk,
+ block_buf, ino);
+ if (retval)
+ goto out;
+ /*
+ * If refcount is greater than 1, we might see
+ * the same block referenced by other inodes
+ * later.
+ */
+ if (header->h_refcount > 1)
+ BLK_ADD_CACHE(blk, blk_cache);
+ }
+ }
+ }
+ retval = 0;
+out:
+ if (scan)
+ ext2fs_close_inode_scan(scan);
+ return retval;
+
+}
static errcode_t inode_scan_and_fix(ext2_resize_t rfs)
{
struct process_block_struct pb;
@@ -1996,6 +2135,7 @@ static errcode_t inode_scan_and_fix(ext2_resize_t rfs)
char *block_buf = 0;
ext2_ino_t start_to_move;
int inode_size;
+ int update_ea_inode_refs = 0;
if ((rfs->old_fs->group_desc_count <=
rfs->new_fs->group_desc_count) &&
@@ -2057,15 +2197,6 @@ static errcode_t inode_scan_and_fix(ext2_resize_t rfs)
if (ino <= start_to_move)
goto remap_blocks; /* Don't need to move inode. */
- /*
- * Moving an extended attribute inode requires updating all inodes
- * that reference it which is a lot more involved.
- */
- if (inode->i_flags & EXT4_EA_INODE_FL) {
- retval = EXT2_ET_CANNOT_MOVE_EA_INODE;
- goto errout;
- }
-
/*
* Find a new inode. Now that extents and directory blocks
* are tied to the inode number through the checksum, we must
@@ -2077,7 +2208,15 @@ static errcode_t inode_scan_and_fix(ext2_resize_t rfs)
ext2fs_inode_alloc_stats2(rfs->new_fs, new_inode, +1,
pb.is_dir);
- inode->i_ctime = time(0);
+ /*
+ * i_ctime field in xattr inodes contain a portion of the ref
+ * count, do not overwrite.
+ */
+ if (inode->i_flags & EXT4_EA_INODE_FL)
+ update_ea_inode_refs = 1;
+ else
+ inode->i_ctime = time(0);
+
retval = ext2fs_write_inode_full(rfs->old_fs, new_inode,
inode, inode_size);
if (retval)
@@ -2143,6 +2282,14 @@ remap_blocks:
goto errout;
}
}
+
+ if (update_ea_inode_refs &&
+ ext2fs_has_feature_ea_inode(rfs->new_fs->super)) {
+ retval = fix_ea_inode_refs(rfs, inode, block_buf,
+ start_to_move);
+ if (retval)
+ goto errout;
+ }
io_channel_flush(rfs->old_fs->io);
errout:
--
2.13.2.932.g7449e964c-goog
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