[PATCH 13/20] udf: Implement adding of dir entries using new iteration code

[Jan Kara <jack@suse.cz>]

Implement function udf_fiiter_add_entry() adding new directory entries
using new directory iteration code.

Signed-off-by: Jan Kara <jack@suse.cz>
---
 fs/udf/directory.c |  57 ++++++++++++++++++++++++
 fs/udf/namei.c     | 106 +++++++++++++++++++++++++++++++++++++++++++++
 fs/udf/udfdecl.h   |   2 +
 3 files changed, 165 insertions(+)

diff --git a/fs/udf/directory.c b/fs/udf/directory.c
index 66117e834e29..9b5e4f6a9dd1 100644
--- a/fs/udf/directory.c
+++ b/fs/udf/directory.c
@@ -413,6 +413,63 @@ void udf_fiiter_write_fi(struct udf_fileident_iter *iter, uint8_t *impuse)
 	inode_inc_iversion(iter->dir);
 }
 
+void udf_fiiter_update_elen(struct udf_fileident_iter *iter, uint32_t new_elen)
+{
+	struct udf_inode_info *iinfo = UDF_I(iter->dir);
+	int diff = new_elen - iter->elen;
+
+	/* Skip update when we already went past the last extent */
+	if (!iter->elen)
+		return;
+	iter->elen = new_elen;
+	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
+		iter->epos.offset -= sizeof(struct short_ad);
+	else if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
+		iter->epos.offset -= sizeof(struct long_ad);
+	udf_write_aext(iter->dir, &iter->epos, &iter->eloc, iter->elen, 1);
+	iinfo->i_lenExtents += diff;
+	mark_inode_dirty(iter->dir);
+}
+
+/* Append new block to directory. @iter is expected to point at EOF */
+int udf_fiiter_append_blk(struct udf_fileident_iter *iter)
+{
+	struct udf_inode_info *iinfo = UDF_I(iter->dir);
+	int blksize = 1 << iter->dir->i_blkbits;
+	struct buffer_head *bh;
+	sector_t block;
+	uint32_t old_elen = iter->elen;
+	int err;
+
+	if (WARN_ON_ONCE(iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB))
+		return -EINVAL;
+
+	/* Round up last extent in the file */
+	udf_fiiter_update_elen(iter, ALIGN(iter->elen, blksize));
+
+	/* Allocate new block and refresh mapping information */
+	block = iinfo->i_lenExtents >> iter->dir->i_blkbits;
+	bh = udf_bread(iter->dir, block, 1, &err);
+	if (!bh) {
+		udf_fiiter_update_elen(iter, old_elen);
+		return err;
+	}
+	if (inode_bmap(iter->dir, block, &iter->epos, &iter->eloc, &iter->elen,
+		       &iter->loffset) != (EXT_RECORDED_ALLOCATED >> 30)) {
+		udf_err(iter->dir->i_sb,
+			"block %llu not allocated in directory (ino %lu)\n",
+			(unsigned long long)block, iter->dir->i_ino);
+		return -EFSCORRUPTED;
+	}
+	if (!(iter->pos & (blksize - 1))) {
+		brelse(iter->bh[0]);
+		iter->bh[0] = bh;
+	} else {
+		iter->bh[1] = bh;
+	}
+	return 0;
+}
+
 struct fileIdentDesc *udf_fileident_read(struct inode *dir, loff_t *nf_pos,
 					 struct udf_fileident_bh *fibh,
 					 struct fileIdentDesc *cfi,
diff --git a/fs/udf/namei.c b/fs/udf/namei.c
index d0ffd2083519..cfcdc9ec8fe3 100644
--- a/fs/udf/namei.c
+++ b/fs/udf/namei.c
@@ -472,6 +472,112 @@ static struct buffer_head *udf_expand_dir_adinicb(struct inode *inode,
 	return dbh;
 }
 
+static int udf_fiiter_add_entry(struct inode *dir, struct dentry *dentry,
+				struct udf_fileident_iter *iter)
+{
+	struct udf_inode_info *dinfo = UDF_I(dir);
+	int nfidlen, namelen = 0;
+	int ret;
+	int off, blksize = 1 << dir->i_blkbits;
+	udf_pblk_t block;
+	char name[UDF_NAME_LEN_CS0];
+
+	if (dentry) {
+		if (!dentry->d_name.len)
+			return -EINVAL;
+		namelen = udf_put_filename(dir->i_sb, dentry->d_name.name,
+					   dentry->d_name.len,
+					   name, UDF_NAME_LEN_CS0);
+		if (!namelen)
+			return -ENAMETOOLONG;
+	}
+	nfidlen = ALIGN(sizeof(struct fileIdentDesc) + namelen, UDF_NAME_PAD);
+
+	for (ret = udf_fiiter_init(iter, dir, 0);
+	     !ret && iter->pos < dir->i_size;
+	     ret = udf_fiiter_advance(iter)) {
+		if (iter->fi.fileCharacteristics & FID_FILE_CHAR_DELETED) {
+			if (udf_dir_entry_len(&iter->fi) == nfidlen) {
+				iter->fi.descTag.tagSerialNum = cpu_to_le16(1);
+				iter->fi.fileVersionNum = cpu_to_le16(1);
+				iter->fi.fileCharacteristics = 0;
+				iter->fi.lengthFileIdent = namelen;
+				iter->fi.lengthOfImpUse = cpu_to_le16(0);
+				memcpy(iter->namebuf, name, namelen);
+				iter->name = iter->namebuf;
+				return 0;
+			}
+		}
+	}
+	if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB &&
+	    blksize - udf_ext0_offset(dir) - iter->pos < nfidlen) {
+		struct buffer_head *retbh;
+
+		udf_fiiter_release(iter);
+		/*
+		 * FIXME: udf_expand_dir_adinicb does not need to return bh
+		 * once other users are gone
+		 */
+		retbh = udf_expand_dir_adinicb(dir, &block, &ret);
+		if (!retbh)
+			return ret;
+		brelse(retbh);
+		ret = udf_fiiter_init(iter, dir, dir->i_size);
+		if (ret < 0)
+			return ret;
+	}
+
+	/* Get blocknumber to use for entry tag */
+	if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
+		block = dinfo->i_location.logicalBlockNum;
+	} else {
+		block = iter->eloc.logicalBlockNum +
+				((iter->elen - 1) >> dir->i_blkbits);
+	}
+	off = iter->pos & (blksize - 1);
+	if (!off)
+		off = blksize;
+	/* Entry fits into current block? */
+	if (blksize - udf_ext0_offset(dir) - off >= nfidlen)
+		goto store_fi;
+
+	ret = udf_fiiter_append_blk(iter);
+	if (ret) {
+		udf_fiiter_release(iter);
+		return ret;
+	}
+
+	/* Entry will be completely in the new block? Update tag location... */
+	if (!(iter->pos & (blksize - 1)))
+		block = iter->eloc.logicalBlockNum +
+				((iter->elen - 1) >> dir->i_blkbits);
+store_fi:
+	memset(&iter->fi, 0, sizeof(struct fileIdentDesc));
+	if (UDF_SB(dir->i_sb)->s_udfrev >= 0x0200)
+		udf_new_tag((char *)(&iter->fi), TAG_IDENT_FID, 3, 1, block,
+			    sizeof(struct tag));
+	else
+		udf_new_tag((char *)(&iter->fi), TAG_IDENT_FID, 2, 1, block,
+			    sizeof(struct tag));
+	iter->fi.fileVersionNum = cpu_to_le16(1);
+	iter->fi.lengthFileIdent = namelen;
+	iter->fi.lengthOfImpUse = cpu_to_le16(0);
+	memcpy(iter->namebuf, name, namelen);
+	iter->name = iter->namebuf;
+
+	dir->i_size += nfidlen;
+	if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
+		dinfo->i_lenAlloc += nfidlen;
+	} else {
+		/* Truncate last extent to proper size */
+		udf_fiiter_update_elen(iter, iter->elen -
+					(dinfo->i_lenExtents - dir->i_size));
+	}
+	mark_inode_dirty(dir);
+
+	return 0;
+}
+
 static struct fileIdentDesc *udf_add_entry(struct inode *dir,
 					   struct dentry *dentry,
 					   struct udf_fileident_bh *fibh,
diff --git a/fs/udf/udfdecl.h b/fs/udf/udfdecl.h
index 676fa2996ffe..e47b2f0c3e05 100644
--- a/fs/udf/udfdecl.h
+++ b/fs/udf/udfdecl.h
@@ -264,6 +264,8 @@ int udf_fiiter_init(struct udf_fileident_iter *iter, struct inode *dir,
 int udf_fiiter_advance(struct udf_fileident_iter *iter);
 void udf_fiiter_release(struct udf_fileident_iter *iter);
 void udf_fiiter_write_fi(struct udf_fileident_iter *iter, uint8_t *impuse);
+void udf_fiiter_update_elen(struct udf_fileident_iter *iter, uint32_t new_elen);
+int udf_fiiter_append_blk(struct udf_fileident_iter *iter);
 extern struct fileIdentDesc *udf_fileident_read(struct inode *, loff_t *,
 						struct udf_fileident_bh *,
 						struct fileIdentDesc *,
-- 
2.35.3