Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 237 insertions, 0 deletions

diff --git a/fs/udf/dir.c b/fs/udf/dir.c
new file mode 100644
index 000000000..d0f92a52e
--- /dev/null
+++ b/fs/udf/dir.c
@@ -0,0 +1,237 @@
+/*
+ * dir.c
+ *
+ * PURPOSE
+ *  Directory handling routines for the OSTA-UDF(tm) filesystem.
+ *
+ * COPYRIGHT
+ *	This file is distributed under the terms of the GNU General Public
+ *	License (GPL). Copies of the GPL can be obtained from:
+ *		ftp://prep.ai.mit.edu/pub/gnu/GPL
+ *	Each contributing author retains all rights to their own work.
+ *
+ *  (C) 1998-2004 Ben Fennema
+ *
+ * HISTORY
+ *
+ *  10/05/98 dgb  Split directory operations into its own file
+ *                Implemented directory reads via do_udf_readdir
+ *  10/06/98      Made directory operations work!
+ *  11/17/98      Rewrote directory to support ICBTAG_FLAG_AD_LONG
+ *  11/25/98 blf  Rewrote directory handling (readdir+lookup) to support reading
+ *                across blocks.
+ *  12/12/98      Split out the lookup code to namei.c. bulk of directory
+ *                code now in directory.c:udf_fileident_read.
+ */
+
+#include "udfdecl.h"
+
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/bio.h>
+#include <linux/iversion.h>
+
+#include "udf_i.h"
+#include "udf_sb.h"
+
+
+static int udf_readdir(struct file *file, struct dir_context *ctx)
+{
+	struct inode *dir = file_inode(file);
+	struct udf_inode_info *iinfo = UDF_I(dir);
+	struct udf_fileident_bh fibh = { .sbh = NULL, .ebh = NULL};
+	struct fileIdentDesc *fi = NULL;
+	struct fileIdentDesc cfi;
+	udf_pblk_t block, iblock;
+	loff_t nf_pos, emit_pos = 0;
+	int flen;
+	unsigned char *fname = NULL, *copy_name = NULL;
+	unsigned char *nameptr;
+	uint16_t liu;
+	uint8_t lfi;
+	loff_t size = udf_ext0_offset(dir) + dir->i_size;
+	struct buffer_head *tmp, *bha[16];
+	struct kernel_lb_addr eloc;
+	uint32_t elen;
+	sector_t offset;
+	int i, num, ret = 0;
+	struct extent_position epos = { NULL, 0, {0, 0} };
+	struct super_block *sb = dir->i_sb;
+	bool pos_valid = false;
+
+	if (ctx->pos == 0) {
+		if (!dir_emit_dot(file, ctx))
+			return 0;
+		ctx->pos = 1;
+	}
+	nf_pos = (ctx->pos - 1) << 2;
+	if (nf_pos >= size)
+		goto out;
+
+	/*
+	 * Something changed since last readdir (either lseek was called or dir
+	 * changed)?  We need to verify the position correctly points at the
+	 * beginning of some dir entry so that the directory parsing code does
+	 * not get confused. Since UDF does not have any reliable way of
+	 * identifying beginning of dir entry (names are under user control),
+	 * we need to scan the directory from the beginning.
+	 */
+	if (!inode_eq_iversion(dir, file->f_version)) {
+		emit_pos = nf_pos;
+		nf_pos = 0;
+	} else {
+		pos_valid = true;
+	}
+
+	fname = kmalloc(UDF_NAME_LEN, GFP_NOFS);
+	if (!fname) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	if (nf_pos == 0)
+		nf_pos = udf_ext0_offset(dir);
+
+	fibh.soffset = fibh.eoffset = nf_pos & (sb->s_blocksize - 1);
+	if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
+		if (inode_bmap(dir, nf_pos >> sb->s_blocksize_bits,
+		    &epos, &eloc, &elen, &offset)
+		    != (EXT_RECORDED_ALLOCATED >> 30)) {
+			ret = -ENOENT;
+			goto out;
+		}
+		block = udf_get_lb_pblock(sb, &eloc, offset);
+		if ((++offset << sb->s_blocksize_bits) < elen) {
+			if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
+				epos.offset -= sizeof(struct short_ad);
+			else if (iinfo->i_alloc_type ==
+					ICBTAG_FLAG_AD_LONG)
+				epos.offset -= sizeof(struct long_ad);
+		} else {
+			offset = 0;
+		}
+
+		if (!(fibh.sbh = fibh.ebh = udf_tread(sb, block))) {
+			ret = -EIO;
+			goto out;
+		}
+
+		if (!(offset & ((16 >> (sb->s_blocksize_bits - 9)) - 1))) {
+			i = 16 >> (sb->s_blocksize_bits - 9);
+			if (i + offset > (elen >> sb->s_blocksize_bits))
+				i = (elen >> sb->s_blocksize_bits) - offset;
+			for (num = 0; i > 0; i--) {
+				block = udf_get_lb_pblock(sb, &eloc, offset + i);
+				tmp = udf_tgetblk(sb, block);
+				if (tmp && !buffer_uptodate(tmp) && !buffer_locked(tmp))
+					bha[num++] = tmp;
+				else
+					brelse(tmp);
+			}
+			if (num) {
+				ll_rw_block(REQ_OP_READ, REQ_RAHEAD, num, bha);
+				for (i = 0; i < num; i++)
+					brelse(bha[i]);
+			}
+		}
+	}
+
+	while (nf_pos < size) {
+		struct kernel_lb_addr tloc;
+		loff_t cur_pos = nf_pos;
+
+		/* Update file position only if we got past the current one */
+		if (nf_pos >= emit_pos) {
+			ctx->pos = (nf_pos >> 2) + 1;
+			pos_valid = true;
+		}
+
+		fi = udf_fileident_read(dir, &nf_pos, &fibh, &cfi, &epos, &eloc,
+					&elen, &offset);
+		if (!fi)
+			goto out;
+		/* Still not at offset where user asked us to read from? */
+		if (cur_pos < emit_pos)
+			continue;
+
+		liu = le16_to_cpu(cfi.lengthOfImpUse);
+		lfi = cfi.lengthFileIdent;
+
+		if (fibh.sbh == fibh.ebh) {
+			nameptr = fi->fileIdent + liu;
+		} else {
+			int poffset;	/* Unpaded ending offset */
+
+			poffset = fibh.soffset + sizeof(struct fileIdentDesc) + liu + lfi;
+
+			if (poffset >= lfi) {
+				nameptr = (char *)(fibh.ebh->b_data + poffset - lfi);
+			} else {
+				if (!copy_name) {
+					copy_name = kmalloc(UDF_NAME_LEN,
+							    GFP_NOFS);
+					if (!copy_name) {
+						ret = -ENOMEM;
+						goto out;
+					}
+				}
+				nameptr = copy_name;
+				memcpy(nameptr, fi->fileIdent + liu,
+				       lfi - poffset);
+				memcpy(nameptr + lfi - poffset,
+				       fibh.ebh->b_data, poffset);
+			}
+		}
+
+		if ((cfi.fileCharacteristics & FID_FILE_CHAR_DELETED) != 0) {
+			if (!UDF_QUERY_FLAG(sb, UDF_FLAG_UNDELETE))
+				continue;
+		}
+
+		if ((cfi.fileCharacteristics & FID_FILE_CHAR_HIDDEN) != 0) {
+			if (!UDF_QUERY_FLAG(sb, UDF_FLAG_UNHIDE))
+				continue;
+		}
+
+		if (cfi.fileCharacteristics & FID_FILE_CHAR_PARENT) {
+			if (!dir_emit_dotdot(file, ctx))
+				goto out;
+			continue;
+		}
+
+		flen = udf_get_filename(sb, nameptr, lfi, fname, UDF_NAME_LEN);
+		if (flen < 0)
+			continue;
+
+		tloc = lelb_to_cpu(cfi.icb.extLocation);
+		iblock = udf_get_lb_pblock(sb, &tloc, 0);
+		if (!dir_emit(ctx, fname, flen, iblock, DT_UNKNOWN))
+			goto out;
+	} /* end while */
+
+	ctx->pos = (nf_pos >> 2) + 1;
+	pos_valid = true;
+
+out:
+	if (pos_valid)
+		file->f_version = inode_query_iversion(dir);
+	if (fibh.sbh != fibh.ebh)
+		brelse(fibh.ebh);
+	brelse(fibh.sbh);
+	brelse(epos.bh);
+	kfree(fname);
+	kfree(copy_name);
+
+	return ret;
+}
+
+/* readdir and lookup functions */
+const struct file_operations udf_dir_operations = {
+	.llseek			= generic_file_llseek,
+	.read			= generic_read_dir,
+	.iterate_shared		= udf_readdir,
+	.unlocked_ioctl		= udf_ioctl,
+	.fsync			= generic_file_fsync,
+};