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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/udf/misc.c
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Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'fs/udf/misc.c')
-rw-r--r--fs/udf/misc.c313
1 files changed, 313 insertions, 0 deletions
diff --git a/fs/udf/misc.c b/fs/udf/misc.c
new file mode 100644
index 00000000000..fd321f9ace8
--- /dev/null
+++ b/fs/udf/misc.c
@@ -0,0 +1,313 @@
+/*
+ * misc.c
+ *
+ * PURPOSE
+ * Miscellaneous routines for the OSTA-UDF(tm) filesystem.
+ *
+ * CONTACTS
+ * E-mail regarding any portion of the Linux UDF file system should be
+ * directed to the development team mailing list (run by majordomo):
+ * linux_udf@hpesjro.fc.hp.com
+ *
+ * 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 Dave Boynton
+ * (C) 1998-2004 Ben Fennema
+ * (C) 1999-2000 Stelias Computing Inc
+ *
+ * HISTORY
+ *
+ * 04/19/99 blf partial support for reading/writing specific EA's
+ */
+
+#include "udfdecl.h"
+
+#include <linux/fs.h>
+#include <linux/string.h>
+#include <linux/udf_fs.h>
+#include <linux/buffer_head.h>
+
+#include "udf_i.h"
+#include "udf_sb.h"
+
+struct buffer_head *
+udf_tgetblk(struct super_block *sb, int block)
+{
+ if (UDF_QUERY_FLAG(sb, UDF_FLAG_VARCONV))
+ return sb_getblk(sb, udf_fixed_to_variable(block));
+ else
+ return sb_getblk(sb, block);
+}
+
+struct buffer_head *
+udf_tread(struct super_block *sb, int block)
+{
+ if (UDF_QUERY_FLAG(sb, UDF_FLAG_VARCONV))
+ return sb_bread(sb, udf_fixed_to_variable(block));
+ else
+ return sb_bread(sb, block);
+}
+
+struct genericFormat *
+udf_add_extendedattr(struct inode * inode, uint32_t size, uint32_t type,
+ uint8_t loc)
+{
+ uint8_t *ea = NULL, *ad = NULL;
+ int offset;
+ uint16_t crclen;
+ int i;
+
+ ea = UDF_I_DATA(inode);
+ if (UDF_I_LENEATTR(inode))
+ ad = UDF_I_DATA(inode) + UDF_I_LENEATTR(inode);
+ else
+ {
+ ad = ea;
+ size += sizeof(struct extendedAttrHeaderDesc);
+ }
+
+ offset = inode->i_sb->s_blocksize - udf_file_entry_alloc_offset(inode) -
+ UDF_I_LENALLOC(inode);
+
+ /* TODO - Check for FreeEASpace */
+
+ if (loc & 0x01 && offset >= size)
+ {
+ struct extendedAttrHeaderDesc *eahd;
+ eahd = (struct extendedAttrHeaderDesc *)ea;
+
+ if (UDF_I_LENALLOC(inode))
+ {
+ memmove(&ad[size], ad, UDF_I_LENALLOC(inode));
+ }
+
+ if (UDF_I_LENEATTR(inode))
+ {
+ /* check checksum/crc */
+ if (le16_to_cpu(eahd->descTag.tagIdent) != TAG_IDENT_EAHD ||
+ le32_to_cpu(eahd->descTag.tagLocation) != UDF_I_LOCATION(inode).logicalBlockNum)
+ {
+ return NULL;
+ }
+ }
+ else
+ {
+ size -= sizeof(struct extendedAttrHeaderDesc);
+ UDF_I_LENEATTR(inode) += sizeof(struct extendedAttrHeaderDesc);
+ eahd->descTag.tagIdent = cpu_to_le16(TAG_IDENT_EAHD);
+ if (UDF_SB_UDFREV(inode->i_sb) >= 0x0200)
+ eahd->descTag.descVersion = cpu_to_le16(3);
+ else
+ eahd->descTag.descVersion = cpu_to_le16(2);
+ eahd->descTag.tagSerialNum = cpu_to_le16(UDF_SB_SERIALNUM(inode->i_sb));
+ eahd->descTag.tagLocation = cpu_to_le32(UDF_I_LOCATION(inode).logicalBlockNum);
+ eahd->impAttrLocation = cpu_to_le32(0xFFFFFFFF);
+ eahd->appAttrLocation = cpu_to_le32(0xFFFFFFFF);
+ }
+
+ offset = UDF_I_LENEATTR(inode);
+ if (type < 2048)
+ {
+ if (le32_to_cpu(eahd->appAttrLocation) < UDF_I_LENEATTR(inode))
+ {
+ uint32_t aal = le32_to_cpu(eahd->appAttrLocation);
+ memmove(&ea[offset - aal + size],
+ &ea[aal], offset - aal);
+ offset -= aal;
+ eahd->appAttrLocation = cpu_to_le32(aal + size);
+ }
+ if (le32_to_cpu(eahd->impAttrLocation) < UDF_I_LENEATTR(inode))
+ {
+ uint32_t ial = le32_to_cpu(eahd->impAttrLocation);
+ memmove(&ea[offset - ial + size],
+ &ea[ial], offset - ial);
+ offset -= ial;
+ eahd->impAttrLocation = cpu_to_le32(ial + size);
+ }
+ }
+ else if (type < 65536)
+ {
+ if (le32_to_cpu(eahd->appAttrLocation) < UDF_I_LENEATTR(inode))
+ {
+ uint32_t aal = le32_to_cpu(eahd->appAttrLocation);
+ memmove(&ea[offset - aal + size],
+ &ea[aal], offset - aal);
+ offset -= aal;
+ eahd->appAttrLocation = cpu_to_le32(aal + size);
+ }
+ }
+ /* rewrite CRC + checksum of eahd */
+ crclen = sizeof(struct extendedAttrHeaderDesc) - sizeof(tag);
+ eahd->descTag.descCRCLength = cpu_to_le16(crclen);
+ eahd->descTag.descCRC = cpu_to_le16(udf_crc((char *)eahd + sizeof(tag), crclen, 0));
+ eahd->descTag.tagChecksum = 0;
+ for (i=0; i<16; i++)
+ if (i != 4)
+ eahd->descTag.tagChecksum += ((uint8_t *)&(eahd->descTag))[i];
+ UDF_I_LENEATTR(inode) += size;
+ return (struct genericFormat *)&ea[offset];
+ }
+ if (loc & 0x02)
+ {
+ }
+ return NULL;
+}
+
+struct genericFormat *
+udf_get_extendedattr(struct inode *inode, uint32_t type, uint8_t subtype)
+{
+ struct genericFormat *gaf;
+ uint8_t *ea = NULL;
+ uint32_t offset;
+
+ ea = UDF_I_DATA(inode);
+
+ if (UDF_I_LENEATTR(inode))
+ {
+ struct extendedAttrHeaderDesc *eahd;
+ eahd = (struct extendedAttrHeaderDesc *)ea;
+
+ /* check checksum/crc */
+ if (le16_to_cpu(eahd->descTag.tagIdent) != TAG_IDENT_EAHD ||
+ le32_to_cpu(eahd->descTag.tagLocation) != UDF_I_LOCATION(inode).logicalBlockNum)
+ {
+ return NULL;
+ }
+
+ if (type < 2048)
+ offset = sizeof(struct extendedAttrHeaderDesc);
+ else if (type < 65536)
+ offset = le32_to_cpu(eahd->impAttrLocation);
+ else
+ offset = le32_to_cpu(eahd->appAttrLocation);
+
+ while (offset < UDF_I_LENEATTR(inode))
+ {
+ gaf = (struct genericFormat *)&ea[offset];
+ if (le32_to_cpu(gaf->attrType) == type && gaf->attrSubtype == subtype)
+ return gaf;
+ else
+ offset += le32_to_cpu(gaf->attrLength);
+ }
+ }
+ return NULL;
+}
+
+/*
+ * udf_read_tagged
+ *
+ * PURPOSE
+ * Read the first block of a tagged descriptor.
+ *
+ * HISTORY
+ * July 1, 1997 - Andrew E. Mileski
+ * Written, tested, and released.
+ */
+struct buffer_head *
+udf_read_tagged(struct super_block *sb, uint32_t block, uint32_t location, uint16_t *ident)
+{
+ tag *tag_p;
+ struct buffer_head *bh = NULL;
+ register uint8_t checksum;
+ register int i;
+
+ /* Read the block */
+ if (block == 0xFFFFFFFF)
+ return NULL;
+
+ bh = udf_tread(sb, block + UDF_SB_SESSION(sb));
+ if (!bh)
+ {
+ udf_debug("block=%d, location=%d: read failed\n", block + UDF_SB_SESSION(sb), location);
+ return NULL;
+ }
+
+ tag_p = (tag *)(bh->b_data);
+
+ *ident = le16_to_cpu(tag_p->tagIdent);
+
+ if ( location != le32_to_cpu(tag_p->tagLocation) )
+ {
+ udf_debug("location mismatch block %u, tag %u != %u\n",
+ block + UDF_SB_SESSION(sb), le32_to_cpu(tag_p->tagLocation), location);
+ goto error_out;
+ }
+
+ /* Verify the tag checksum */
+ checksum = 0U;
+ for (i = 0; i < 4; i++)
+ checksum += (uint8_t)(bh->b_data[i]);
+ for (i = 5; i < 16; i++)
+ checksum += (uint8_t)(bh->b_data[i]);
+ if (checksum != tag_p->tagChecksum) {
+ printk(KERN_ERR "udf: tag checksum failed block %d\n", block);
+ goto error_out;
+ }
+
+ /* Verify the tag version */
+ if (le16_to_cpu(tag_p->descVersion) != 0x0002U &&
+ le16_to_cpu(tag_p->descVersion) != 0x0003U)
+ {
+ udf_debug("tag version 0x%04x != 0x0002 || 0x0003 block %d\n",
+ le16_to_cpu(tag_p->descVersion), block);
+ goto error_out;
+ }
+
+ /* Verify the descriptor CRC */
+ if (le16_to_cpu(tag_p->descCRCLength) + sizeof(tag) > sb->s_blocksize ||
+ le16_to_cpu(tag_p->descCRC) == udf_crc(bh->b_data + sizeof(tag),
+ le16_to_cpu(tag_p->descCRCLength), 0))
+ {
+ return bh;
+ }
+ udf_debug("Crc failure block %d: crc = %d, crclen = %d\n",
+ block + UDF_SB_SESSION(sb), le16_to_cpu(tag_p->descCRC), le16_to_cpu(tag_p->descCRCLength));
+
+error_out:
+ brelse(bh);
+ return NULL;
+}
+
+struct buffer_head *
+udf_read_ptagged(struct super_block *sb, kernel_lb_addr loc, uint32_t offset, uint16_t *ident)
+{
+ return udf_read_tagged(sb, udf_get_lb_pblock(sb, loc, offset),
+ loc.logicalBlockNum + offset, ident);
+}
+
+void udf_release_data(struct buffer_head *bh)
+{
+ if (bh)
+ brelse(bh);
+}
+
+void udf_update_tag(char *data, int length)
+{
+ tag *tptr = (tag *)data;
+ int i;
+
+ length -= sizeof(tag);
+
+ tptr->tagChecksum = 0;
+ tptr->descCRCLength = cpu_to_le16(length);
+ tptr->descCRC = cpu_to_le16(udf_crc(data + sizeof(tag), length, 0));
+
+ for (i=0; i<16; i++)
+ if (i != 4)
+ tptr->tagChecksum += (uint8_t)(data[i]);
+}
+
+void udf_new_tag(char *data, uint16_t ident, uint16_t version, uint16_t snum,
+ uint32_t loc, int length)
+{
+ tag *tptr = (tag *)data;
+ tptr->tagIdent = cpu_to_le16(ident);
+ tptr->descVersion = cpu_to_le16(version);
+ tptr->tagSerialNum = cpu_to_le16(snum);
+ tptr->tagLocation = cpu_to_le32(loc);
+ udf_update_tag(data, length);
+}