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807 lines
18 KiB
807 lines
18 KiB
// SPDX-License-Identifier: GPL-2.0 |
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/* |
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* linux/fs/isofs/rock.c |
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* |
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* (C) 1992, 1993 Eric Youngdale |
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* |
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* Rock Ridge Extensions to iso9660 |
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*/ |
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|
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#include <linux/slab.h> |
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#include <linux/pagemap.h> |
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|
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#include "isofs.h" |
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#include "rock.h" |
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|
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/* |
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* These functions are designed to read the system areas of a directory record |
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* and extract relevant information. There are different functions provided |
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* depending upon what information we need at the time. One function fills |
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* out an inode structure, a second one extracts a filename, a third one |
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* returns a symbolic link name, and a fourth one returns the extent number |
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* for the file. |
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*/ |
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|
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#define SIG(A,B) ((A) | ((B) << 8)) /* isonum_721() */ |
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|
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struct rock_state { |
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void *buffer; |
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unsigned char *chr; |
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int len; |
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int cont_size; |
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int cont_extent; |
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int cont_offset; |
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int cont_loops; |
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struct inode *inode; |
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}; |
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|
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/* |
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* This is a way of ensuring that we have something in the system |
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* use fields that is compatible with Rock Ridge. Return zero on success. |
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*/ |
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|
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static int check_sp(struct rock_ridge *rr, struct inode *inode) |
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{ |
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if (rr->u.SP.magic[0] != 0xbe) |
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return -1; |
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if (rr->u.SP.magic[1] != 0xef) |
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return -1; |
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ISOFS_SB(inode->i_sb)->s_rock_offset = rr->u.SP.skip; |
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return 0; |
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} |
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|
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static void setup_rock_ridge(struct iso_directory_record *de, |
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struct inode *inode, struct rock_state *rs) |
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{ |
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rs->len = sizeof(struct iso_directory_record) + de->name_len[0]; |
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if (rs->len & 1) |
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(rs->len)++; |
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rs->chr = (unsigned char *)de + rs->len; |
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rs->len = *((unsigned char *)de) - rs->len; |
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if (rs->len < 0) |
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rs->len = 0; |
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|
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if (ISOFS_SB(inode->i_sb)->s_rock_offset != -1) { |
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rs->len -= ISOFS_SB(inode->i_sb)->s_rock_offset; |
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rs->chr += ISOFS_SB(inode->i_sb)->s_rock_offset; |
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if (rs->len < 0) |
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rs->len = 0; |
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} |
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} |
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|
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static void init_rock_state(struct rock_state *rs, struct inode *inode) |
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{ |
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memset(rs, 0, sizeof(*rs)); |
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rs->inode = inode; |
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} |
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|
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/* Maximum number of Rock Ridge continuation entries */ |
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#define RR_MAX_CE_ENTRIES 32 |
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|
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/* |
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* Returns 0 if the caller should continue scanning, 1 if the scan must end |
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* and -ve on error. |
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*/ |
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static int rock_continue(struct rock_state *rs) |
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{ |
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int ret = 1; |
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int blocksize = 1 << rs->inode->i_blkbits; |
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const int min_de_size = offsetof(struct rock_ridge, u); |
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|
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kfree(rs->buffer); |
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rs->buffer = NULL; |
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|
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if ((unsigned)rs->cont_offset > blocksize - min_de_size || |
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(unsigned)rs->cont_size > blocksize || |
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(unsigned)(rs->cont_offset + rs->cont_size) > blocksize) { |
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printk(KERN_NOTICE "rock: corrupted directory entry. " |
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"extent=%d, offset=%d, size=%d\n", |
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rs->cont_extent, rs->cont_offset, rs->cont_size); |
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ret = -EIO; |
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goto out; |
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} |
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|
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if (rs->cont_extent) { |
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struct buffer_head *bh; |
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|
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rs->buffer = kmalloc(rs->cont_size, GFP_KERNEL); |
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if (!rs->buffer) { |
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ret = -ENOMEM; |
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goto out; |
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} |
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ret = -EIO; |
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if (++rs->cont_loops >= RR_MAX_CE_ENTRIES) |
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goto out; |
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bh = sb_bread(rs->inode->i_sb, rs->cont_extent); |
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if (bh) { |
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memcpy(rs->buffer, bh->b_data + rs->cont_offset, |
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rs->cont_size); |
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put_bh(bh); |
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rs->chr = rs->buffer; |
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rs->len = rs->cont_size; |
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rs->cont_extent = 0; |
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rs->cont_size = 0; |
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rs->cont_offset = 0; |
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return 0; |
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} |
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printk("Unable to read rock-ridge attributes\n"); |
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} |
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out: |
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kfree(rs->buffer); |
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rs->buffer = NULL; |
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return ret; |
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} |
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|
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/* |
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* We think there's a record of type `sig' at rs->chr. Parse the signature |
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* and make sure that there's really room for a record of that type. |
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*/ |
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static int rock_check_overflow(struct rock_state *rs, int sig) |
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{ |
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int len; |
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|
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switch (sig) { |
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case SIG('S', 'P'): |
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len = sizeof(struct SU_SP_s); |
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break; |
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case SIG('C', 'E'): |
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len = sizeof(struct SU_CE_s); |
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break; |
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case SIG('E', 'R'): |
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len = sizeof(struct SU_ER_s); |
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break; |
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case SIG('R', 'R'): |
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len = sizeof(struct RR_RR_s); |
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break; |
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case SIG('P', 'X'): |
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len = sizeof(struct RR_PX_s); |
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break; |
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case SIG('P', 'N'): |
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len = sizeof(struct RR_PN_s); |
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break; |
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case SIG('S', 'L'): |
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len = sizeof(struct RR_SL_s); |
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break; |
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case SIG('N', 'M'): |
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len = sizeof(struct RR_NM_s); |
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break; |
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case SIG('C', 'L'): |
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len = sizeof(struct RR_CL_s); |
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break; |
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case SIG('P', 'L'): |
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len = sizeof(struct RR_PL_s); |
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break; |
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case SIG('T', 'F'): |
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len = sizeof(struct RR_TF_s); |
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break; |
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case SIG('Z', 'F'): |
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len = sizeof(struct RR_ZF_s); |
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break; |
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default: |
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len = 0; |
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break; |
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} |
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len += offsetof(struct rock_ridge, u); |
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if (len > rs->len) { |
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printk(KERN_NOTICE "rock: directory entry would overflow " |
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"storage\n"); |
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printk(KERN_NOTICE "rock: sig=0x%02x, size=%d, remaining=%d\n", |
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sig, len, rs->len); |
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return -EIO; |
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} |
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return 0; |
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} |
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|
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/* |
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* return length of name field; 0: not found, -1: to be ignored |
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*/ |
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int get_rock_ridge_filename(struct iso_directory_record *de, |
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char *retname, struct inode *inode) |
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{ |
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struct rock_state rs; |
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struct rock_ridge *rr; |
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int sig; |
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int retnamlen = 0; |
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int truncate = 0; |
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int ret = 0; |
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char *p; |
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int len; |
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if (!ISOFS_SB(inode->i_sb)->s_rock) |
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return 0; |
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*retname = 0; |
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init_rock_state(&rs, inode); |
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setup_rock_ridge(de, inode, &rs); |
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repeat: |
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|
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while (rs.len > 2) { /* There may be one byte for padding somewhere */ |
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rr = (struct rock_ridge *)rs.chr; |
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/* |
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* Ignore rock ridge info if rr->len is out of range, but |
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* don't return -EIO because that would make the file |
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* invisible. |
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*/ |
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if (rr->len < 3) |
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goto out; /* Something got screwed up here */ |
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sig = isonum_721(rs.chr); |
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if (rock_check_overflow(&rs, sig)) |
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goto eio; |
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rs.chr += rr->len; |
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rs.len -= rr->len; |
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/* |
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* As above, just ignore the rock ridge info if rr->len |
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* is bogus. |
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*/ |
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if (rs.len < 0) |
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goto out; /* Something got screwed up here */ |
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|
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switch (sig) { |
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case SIG('R', 'R'): |
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if ((rr->u.RR.flags[0] & RR_NM) == 0) |
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goto out; |
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break; |
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case SIG('S', 'P'): |
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if (check_sp(rr, inode)) |
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goto out; |
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break; |
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case SIG('C', 'E'): |
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rs.cont_extent = isonum_733(rr->u.CE.extent); |
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rs.cont_offset = isonum_733(rr->u.CE.offset); |
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rs.cont_size = isonum_733(rr->u.CE.size); |
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break; |
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case SIG('N', 'M'): |
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if (truncate) |
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break; |
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if (rr->len < 5) |
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break; |
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/* |
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* If the flags are 2 or 4, this indicates '.' or '..'. |
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* We don't want to do anything with this, because it |
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* screws up the code that calls us. We don't really |
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* care anyways, since we can just use the non-RR |
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* name. |
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*/ |
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if (rr->u.NM.flags & 6) |
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break; |
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|
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if (rr->u.NM.flags & ~1) { |
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printk("Unsupported NM flag settings (%d)\n", |
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rr->u.NM.flags); |
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break; |
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} |
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len = rr->len - 5; |
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if (retnamlen + len >= 254) { |
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truncate = 1; |
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break; |
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} |
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p = memchr(rr->u.NM.name, '\0', len); |
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if (unlikely(p)) |
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len = p - rr->u.NM.name; |
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memcpy(retname + retnamlen, rr->u.NM.name, len); |
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retnamlen += len; |
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retname[retnamlen] = '\0'; |
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break; |
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case SIG('R', 'E'): |
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kfree(rs.buffer); |
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return -1; |
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default: |
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break; |
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} |
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} |
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ret = rock_continue(&rs); |
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if (ret == 0) |
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goto repeat; |
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if (ret == 1) |
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return retnamlen; /* If 0, this file did not have a NM field */ |
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out: |
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kfree(rs.buffer); |
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return ret; |
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eio: |
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ret = -EIO; |
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goto out; |
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} |
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|
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#define RR_REGARD_XA 1 |
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#define RR_RELOC_DE 2 |
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|
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static int |
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parse_rock_ridge_inode_internal(struct iso_directory_record *de, |
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struct inode *inode, int flags) |
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{ |
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int symlink_len = 0; |
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int cnt, sig; |
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unsigned int reloc_block; |
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struct inode *reloc; |
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struct rock_ridge *rr; |
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int rootflag; |
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struct rock_state rs; |
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int ret = 0; |
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|
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if (!ISOFS_SB(inode->i_sb)->s_rock) |
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return 0; |
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|
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init_rock_state(&rs, inode); |
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setup_rock_ridge(de, inode, &rs); |
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if (flags & RR_REGARD_XA) { |
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rs.chr += 14; |
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rs.len -= 14; |
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if (rs.len < 0) |
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rs.len = 0; |
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} |
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|
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repeat: |
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while (rs.len > 2) { /* There may be one byte for padding somewhere */ |
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rr = (struct rock_ridge *)rs.chr; |
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/* |
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* Ignore rock ridge info if rr->len is out of range, but |
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* don't return -EIO because that would make the file |
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* invisible. |
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*/ |
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if (rr->len < 3) |
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goto out; /* Something got screwed up here */ |
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sig = isonum_721(rs.chr); |
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if (rock_check_overflow(&rs, sig)) |
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goto eio; |
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rs.chr += rr->len; |
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rs.len -= rr->len; |
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/* |
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* As above, just ignore the rock ridge info if rr->len |
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* is bogus. |
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*/ |
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if (rs.len < 0) |
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goto out; /* Something got screwed up here */ |
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|
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switch (sig) { |
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#ifndef CONFIG_ZISOFS /* No flag for SF or ZF */ |
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case SIG('R', 'R'): |
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if ((rr->u.RR.flags[0] & |
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(RR_PX | RR_TF | RR_SL | RR_CL)) == 0) |
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goto out; |
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break; |
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#endif |
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case SIG('S', 'P'): |
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if (check_sp(rr, inode)) |
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goto out; |
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break; |
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case SIG('C', 'E'): |
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rs.cont_extent = isonum_733(rr->u.CE.extent); |
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rs.cont_offset = isonum_733(rr->u.CE.offset); |
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rs.cont_size = isonum_733(rr->u.CE.size); |
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break; |
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case SIG('E', 'R'): |
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/* Invalid length of ER tag id? */ |
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if (rr->u.ER.len_id + offsetof(struct rock_ridge, u.ER.data) > rr->len) |
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goto out; |
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ISOFS_SB(inode->i_sb)->s_rock = 1; |
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printk(KERN_DEBUG "ISO 9660 Extensions: "); |
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{ |
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int p; |
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for (p = 0; p < rr->u.ER.len_id; p++) |
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printk(KERN_CONT "%c", rr->u.ER.data[p]); |
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} |
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printk(KERN_CONT "\n"); |
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break; |
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case SIG('P', 'X'): |
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inode->i_mode = isonum_733(rr->u.PX.mode); |
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set_nlink(inode, isonum_733(rr->u.PX.n_links)); |
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i_uid_write(inode, isonum_733(rr->u.PX.uid)); |
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i_gid_write(inode, isonum_733(rr->u.PX.gid)); |
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break; |
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case SIG('P', 'N'): |
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{ |
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int high, low; |
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high = isonum_733(rr->u.PN.dev_high); |
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low = isonum_733(rr->u.PN.dev_low); |
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/* |
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* The Rock Ridge standard specifies that if |
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* sizeof(dev_t) <= 4, then the high field is |
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* unused, and the device number is completely |
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* stored in the low field. Some writers may |
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* ignore this subtlety, |
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* and as a result we test to see if the entire |
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* device number is |
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* stored in the low field, and use that. |
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*/ |
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if ((low & ~0xff) && high == 0) { |
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inode->i_rdev = |
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MKDEV(low >> 8, low & 0xff); |
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} else { |
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inode->i_rdev = |
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MKDEV(high, low); |
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} |
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} |
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break; |
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case SIG('T', 'F'): |
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/* |
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* Some RRIP writers incorrectly place ctime in the |
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* TF_CREATE field. Try to handle this correctly for |
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* either case. |
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*/ |
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/* Rock ridge never appears on a High Sierra disk */ |
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cnt = 0; |
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if (rr->u.TF.flags & TF_CREATE) { |
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inode->i_ctime.tv_sec = |
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iso_date(rr->u.TF.times[cnt++].time, |
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0); |
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inode->i_ctime.tv_nsec = 0; |
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} |
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if (rr->u.TF.flags & TF_MODIFY) { |
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inode->i_mtime.tv_sec = |
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iso_date(rr->u.TF.times[cnt++].time, |
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0); |
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inode->i_mtime.tv_nsec = 0; |
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} |
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if (rr->u.TF.flags & TF_ACCESS) { |
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inode->i_atime.tv_sec = |
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iso_date(rr->u.TF.times[cnt++].time, |
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0); |
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inode->i_atime.tv_nsec = 0; |
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} |
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if (rr->u.TF.flags & TF_ATTRIBUTES) { |
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inode->i_ctime.tv_sec = |
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iso_date(rr->u.TF.times[cnt++].time, |
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0); |
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inode->i_ctime.tv_nsec = 0; |
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} |
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break; |
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case SIG('S', 'L'): |
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{ |
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int slen; |
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struct SL_component *slp; |
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struct SL_component *oldslp; |
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slen = rr->len - 5; |
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slp = &rr->u.SL.link; |
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inode->i_size = symlink_len; |
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while (slen > 1) { |
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rootflag = 0; |
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switch (slp->flags & ~1) { |
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case 0: |
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inode->i_size += |
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slp->len; |
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break; |
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case 2: |
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inode->i_size += 1; |
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break; |
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case 4: |
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inode->i_size += 2; |
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break; |
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case 8: |
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rootflag = 1; |
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inode->i_size += 1; |
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break; |
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default: |
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printk("Symlink component flag " |
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"not implemented\n"); |
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} |
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slen -= slp->len + 2; |
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oldslp = slp; |
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slp = (struct SL_component *) |
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(((char *)slp) + slp->len + 2); |
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|
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if (slen < 2) { |
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if (((rr->u.SL. |
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flags & 1) != 0) |
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&& |
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((oldslp-> |
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flags & 1) == 0)) |
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inode->i_size += |
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1; |
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break; |
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} |
|
|
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/* |
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* If this component record isn't |
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* continued, then append a '/'. |
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*/ |
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if (!rootflag |
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&& (oldslp->flags & 1) == 0) |
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inode->i_size += 1; |
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} |
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} |
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symlink_len = inode->i_size; |
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break; |
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case SIG('R', 'E'): |
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printk(KERN_WARNING "Attempt to read inode for " |
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"relocated directory\n"); |
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goto out; |
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case SIG('C', 'L'): |
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if (flags & RR_RELOC_DE) { |
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printk(KERN_ERR |
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"ISOFS: Recursive directory relocation " |
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"is not supported\n"); |
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goto eio; |
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} |
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reloc_block = isonum_733(rr->u.CL.location); |
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if (reloc_block == ISOFS_I(inode)->i_iget5_block && |
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ISOFS_I(inode)->i_iget5_offset == 0) { |
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printk(KERN_ERR |
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"ISOFS: Directory relocation points to " |
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"itself\n"); |
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goto eio; |
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} |
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ISOFS_I(inode)->i_first_extent = reloc_block; |
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reloc = isofs_iget_reloc(inode->i_sb, reloc_block, 0); |
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if (IS_ERR(reloc)) { |
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ret = PTR_ERR(reloc); |
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goto out; |
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} |
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inode->i_mode = reloc->i_mode; |
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set_nlink(inode, reloc->i_nlink); |
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inode->i_uid = reloc->i_uid; |
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inode->i_gid = reloc->i_gid; |
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inode->i_rdev = reloc->i_rdev; |
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inode->i_size = reloc->i_size; |
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inode->i_blocks = reloc->i_blocks; |
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inode->i_atime = reloc->i_atime; |
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inode->i_ctime = reloc->i_ctime; |
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inode->i_mtime = reloc->i_mtime; |
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iput(reloc); |
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break; |
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#ifdef CONFIG_ZISOFS |
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case SIG('Z', 'F'): { |
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int algo; |
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|
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if (ISOFS_SB(inode->i_sb)->s_nocompress) |
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break; |
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algo = isonum_721(rr->u.ZF.algorithm); |
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if (algo == SIG('p', 'z')) { |
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int block_shift = |
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isonum_711(&rr->u.ZF.parms[1]); |
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if (block_shift > 17) { |
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printk(KERN_WARNING "isofs: " |
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"Can't handle ZF block " |
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"size of 2^%d\n", |
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block_shift); |
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} else { |
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/* |
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* Note: we don't change |
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* i_blocks here |
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*/ |
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ISOFS_I(inode)->i_file_format = |
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isofs_file_compressed; |
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/* |
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* Parameters to compression |
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* algorithm (header size, |
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* block size) |
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*/ |
|
ISOFS_I(inode)->i_format_parm[0] = |
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isonum_711(&rr->u.ZF.parms[0]); |
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ISOFS_I(inode)->i_format_parm[1] = |
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isonum_711(&rr->u.ZF.parms[1]); |
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inode->i_size = |
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isonum_733(rr->u.ZF. |
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real_size); |
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} |
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} else { |
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printk(KERN_WARNING |
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"isofs: Unknown ZF compression " |
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"algorithm: %c%c\n", |
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rr->u.ZF.algorithm[0], |
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rr->u.ZF.algorithm[1]); |
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} |
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break; |
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} |
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#endif |
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default: |
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break; |
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} |
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} |
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ret = rock_continue(&rs); |
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if (ret == 0) |
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goto repeat; |
|
if (ret == 1) |
|
ret = 0; |
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out: |
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kfree(rs.buffer); |
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return ret; |
|
eio: |
|
ret = -EIO; |
|
goto out; |
|
} |
|
|
|
static char *get_symlink_chunk(char *rpnt, struct rock_ridge *rr, char *plimit) |
|
{ |
|
int slen; |
|
int rootflag; |
|
struct SL_component *oldslp; |
|
struct SL_component *slp; |
|
slen = rr->len - 5; |
|
slp = &rr->u.SL.link; |
|
while (slen > 1) { |
|
rootflag = 0; |
|
switch (slp->flags & ~1) { |
|
case 0: |
|
if (slp->len > plimit - rpnt) |
|
return NULL; |
|
memcpy(rpnt, slp->text, slp->len); |
|
rpnt += slp->len; |
|
break; |
|
case 2: |
|
if (rpnt >= plimit) |
|
return NULL; |
|
*rpnt++ = '.'; |
|
break; |
|
case 4: |
|
if (2 > plimit - rpnt) |
|
return NULL; |
|
*rpnt++ = '.'; |
|
*rpnt++ = '.'; |
|
break; |
|
case 8: |
|
if (rpnt >= plimit) |
|
return NULL; |
|
rootflag = 1; |
|
*rpnt++ = '/'; |
|
break; |
|
default: |
|
printk("Symlink component flag not implemented (%d)\n", |
|
slp->flags); |
|
} |
|
slen -= slp->len + 2; |
|
oldslp = slp; |
|
slp = (struct SL_component *)((char *)slp + slp->len + 2); |
|
|
|
if (slen < 2) { |
|
/* |
|
* If there is another SL record, and this component |
|
* record isn't continued, then add a slash. |
|
*/ |
|
if ((!rootflag) && (rr->u.SL.flags & 1) && |
|
!(oldslp->flags & 1)) { |
|
if (rpnt >= plimit) |
|
return NULL; |
|
*rpnt++ = '/'; |
|
} |
|
break; |
|
} |
|
|
|
/* |
|
* If this component record isn't continued, then append a '/'. |
|
*/ |
|
if (!rootflag && !(oldslp->flags & 1)) { |
|
if (rpnt >= plimit) |
|
return NULL; |
|
*rpnt++ = '/'; |
|
} |
|
} |
|
return rpnt; |
|
} |
|
|
|
int parse_rock_ridge_inode(struct iso_directory_record *de, struct inode *inode, |
|
int relocated) |
|
{ |
|
int flags = relocated ? RR_RELOC_DE : 0; |
|
int result = parse_rock_ridge_inode_internal(de, inode, flags); |
|
|
|
/* |
|
* if rockridge flag was reset and we didn't look for attributes |
|
* behind eventual XA attributes, have a look there |
|
*/ |
|
if ((ISOFS_SB(inode->i_sb)->s_rock_offset == -1) |
|
&& (ISOFS_SB(inode->i_sb)->s_rock == 2)) { |
|
result = parse_rock_ridge_inode_internal(de, inode, |
|
flags | RR_REGARD_XA); |
|
} |
|
return result; |
|
} |
|
|
|
/* |
|
* readpage() for symlinks: reads symlink contents into the page and either |
|
* makes it uptodate and returns 0 or returns error (-EIO) |
|
*/ |
|
static int rock_ridge_symlink_readpage(struct file *file, struct page *page) |
|
{ |
|
struct inode *inode = page->mapping->host; |
|
struct iso_inode_info *ei = ISOFS_I(inode); |
|
struct isofs_sb_info *sbi = ISOFS_SB(inode->i_sb); |
|
char *link = page_address(page); |
|
unsigned long bufsize = ISOFS_BUFFER_SIZE(inode); |
|
struct buffer_head *bh; |
|
char *rpnt = link; |
|
unsigned char *pnt; |
|
struct iso_directory_record *raw_de; |
|
unsigned long block, offset; |
|
int sig; |
|
struct rock_ridge *rr; |
|
struct rock_state rs; |
|
int ret; |
|
|
|
if (!sbi->s_rock) |
|
goto error; |
|
|
|
init_rock_state(&rs, inode); |
|
block = ei->i_iget5_block; |
|
bh = sb_bread(inode->i_sb, block); |
|
if (!bh) |
|
goto out_noread; |
|
|
|
offset = ei->i_iget5_offset; |
|
pnt = (unsigned char *)bh->b_data + offset; |
|
|
|
raw_de = (struct iso_directory_record *)pnt; |
|
|
|
/* |
|
* If we go past the end of the buffer, there is some sort of error. |
|
*/ |
|
if (offset + *pnt > bufsize) |
|
goto out_bad_span; |
|
|
|
/* |
|
* Now test for possible Rock Ridge extensions which will override |
|
* some of these numbers in the inode structure. |
|
*/ |
|
|
|
setup_rock_ridge(raw_de, inode, &rs); |
|
|
|
repeat: |
|
while (rs.len > 2) { /* There may be one byte for padding somewhere */ |
|
rr = (struct rock_ridge *)rs.chr; |
|
if (rr->len < 3) |
|
goto out; /* Something got screwed up here */ |
|
sig = isonum_721(rs.chr); |
|
if (rock_check_overflow(&rs, sig)) |
|
goto out; |
|
rs.chr += rr->len; |
|
rs.len -= rr->len; |
|
if (rs.len < 0) |
|
goto out; /* corrupted isofs */ |
|
|
|
switch (sig) { |
|
case SIG('R', 'R'): |
|
if ((rr->u.RR.flags[0] & RR_SL) == 0) |
|
goto out; |
|
break; |
|
case SIG('S', 'P'): |
|
if (check_sp(rr, inode)) |
|
goto out; |
|
break; |
|
case SIG('S', 'L'): |
|
rpnt = get_symlink_chunk(rpnt, rr, |
|
link + (PAGE_SIZE - 1)); |
|
if (rpnt == NULL) |
|
goto out; |
|
break; |
|
case SIG('C', 'E'): |
|
/* This tells is if there is a continuation record */ |
|
rs.cont_extent = isonum_733(rr->u.CE.extent); |
|
rs.cont_offset = isonum_733(rr->u.CE.offset); |
|
rs.cont_size = isonum_733(rr->u.CE.size); |
|
default: |
|
break; |
|
} |
|
} |
|
ret = rock_continue(&rs); |
|
if (ret == 0) |
|
goto repeat; |
|
if (ret < 0) |
|
goto fail; |
|
|
|
if (rpnt == link) |
|
goto fail; |
|
brelse(bh); |
|
*rpnt = '\0'; |
|
SetPageUptodate(page); |
|
unlock_page(page); |
|
return 0; |
|
|
|
/* error exit from macro */ |
|
out: |
|
kfree(rs.buffer); |
|
goto fail; |
|
out_noread: |
|
printk("unable to read i-node block"); |
|
goto fail; |
|
out_bad_span: |
|
printk("symlink spans iso9660 blocks\n"); |
|
fail: |
|
brelse(bh); |
|
error: |
|
SetPageError(page); |
|
unlock_page(page); |
|
return -EIO; |
|
} |
|
|
|
const struct address_space_operations isofs_symlink_aops = { |
|
.readpage = rock_ridge_symlink_readpage |
|
};
|
|
|