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author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 22:20:36 (GMT) |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 22:20:36 (GMT) |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/udf/misc.c | |
download | linux-fsl-qoriq-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.xz |
Linux-2.6.12-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.c | 313 |
1 files changed, 313 insertions, 0 deletions
diff --git a/fs/udf/misc.c b/fs/udf/misc.c new file mode 100644 index 0000000..fd321f9 --- /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); +} |