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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/fs/isofs/rock.c
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/fs/isofs/rock.c')
-rw-r--r--kernel/fs/isofs/rock.c801
1 files changed, 801 insertions, 0 deletions
diff --git a/kernel/fs/isofs/rock.c b/kernel/fs/isofs/rock.c
new file mode 100644
index 000000000..735d7522a
--- /dev/null
+++ b/kernel/fs/isofs/rock.c
@@ -0,0 +1,801 @@
+/*
+ * linux/fs/isofs/rock.c
+ *
+ * (C) 1992, 1993 Eric Youngdale
+ *
+ * Rock Ridge Extensions to iso9660
+ */
+
+#include <linux/slab.h>
+#include <linux/pagemap.h>
+
+#include "isofs.h"
+#include "rock.h"
+
+/*
+ * These functions are designed to read the system areas of a directory record
+ * and extract relevant information. There are different functions provided
+ * depending upon what information we need at the time. One function fills
+ * out an inode structure, a second one extracts a filename, a third one
+ * returns a symbolic link name, and a fourth one returns the extent number
+ * for the file.
+ */
+
+#define SIG(A,B) ((A) | ((B) << 8)) /* isonum_721() */
+
+struct rock_state {
+ void *buffer;
+ unsigned char *chr;
+ int len;
+ int cont_size;
+ int cont_extent;
+ int cont_offset;
+ int cont_loops;
+ struct inode *inode;
+};
+
+/*
+ * This is a way of ensuring that we have something in the system
+ * use fields that is compatible with Rock Ridge. Return zero on success.
+ */
+
+static int check_sp(struct rock_ridge *rr, struct inode *inode)
+{
+ if (rr->u.SP.magic[0] != 0xbe)
+ return -1;
+ if (rr->u.SP.magic[1] != 0xef)
+ return -1;
+ ISOFS_SB(inode->i_sb)->s_rock_offset = rr->u.SP.skip;
+ return 0;
+}
+
+static void setup_rock_ridge(struct iso_directory_record *de,
+ struct inode *inode, struct rock_state *rs)
+{
+ rs->len = sizeof(struct iso_directory_record) + de->name_len[0];
+ if (rs->len & 1)
+ (rs->len)++;
+ rs->chr = (unsigned char *)de + rs->len;
+ rs->len = *((unsigned char *)de) - rs->len;
+ if (rs->len < 0)
+ rs->len = 0;
+
+ if (ISOFS_SB(inode->i_sb)->s_rock_offset != -1) {
+ rs->len -= ISOFS_SB(inode->i_sb)->s_rock_offset;
+ rs->chr += ISOFS_SB(inode->i_sb)->s_rock_offset;
+ if (rs->len < 0)
+ rs->len = 0;
+ }
+}
+
+static void init_rock_state(struct rock_state *rs, struct inode *inode)
+{
+ memset(rs, 0, sizeof(*rs));
+ rs->inode = inode;
+}
+
+/* Maximum number of Rock Ridge continuation entries */
+#define RR_MAX_CE_ENTRIES 32
+
+/*
+ * Returns 0 if the caller should continue scanning, 1 if the scan must end
+ * and -ve on error.
+ */
+static int rock_continue(struct rock_state *rs)
+{
+ int ret = 1;
+ int blocksize = 1 << rs->inode->i_blkbits;
+ const int min_de_size = offsetof(struct rock_ridge, u);
+
+ kfree(rs->buffer);
+ rs->buffer = NULL;
+
+ if ((unsigned)rs->cont_offset > blocksize - min_de_size ||
+ (unsigned)rs->cont_size > blocksize ||
+ (unsigned)(rs->cont_offset + rs->cont_size) > blocksize) {
+ printk(KERN_NOTICE "rock: corrupted directory entry. "
+ "extent=%d, offset=%d, size=%d\n",
+ rs->cont_extent, rs->cont_offset, rs->cont_size);
+ ret = -EIO;
+ goto out;
+ }
+
+ if (rs->cont_extent) {
+ struct buffer_head *bh;
+
+ rs->buffer = kmalloc(rs->cont_size, GFP_KERNEL);
+ if (!rs->buffer) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ ret = -EIO;
+ if (++rs->cont_loops >= RR_MAX_CE_ENTRIES)
+ goto out;
+ bh = sb_bread(rs->inode->i_sb, rs->cont_extent);
+ if (bh) {
+ memcpy(rs->buffer, bh->b_data + rs->cont_offset,
+ rs->cont_size);
+ put_bh(bh);
+ rs->chr = rs->buffer;
+ rs->len = rs->cont_size;
+ rs->cont_extent = 0;
+ rs->cont_size = 0;
+ rs->cont_offset = 0;
+ return 0;
+ }
+ printk("Unable to read rock-ridge attributes\n");
+ }
+out:
+ kfree(rs->buffer);
+ rs->buffer = NULL;
+ return ret;
+}
+
+/*
+ * We think there's a record of type `sig' at rs->chr. Parse the signature
+ * and make sure that there's really room for a record of that type.
+ */
+static int rock_check_overflow(struct rock_state *rs, int sig)
+{
+ int len;
+
+ switch (sig) {
+ case SIG('S', 'P'):
+ len = sizeof(struct SU_SP_s);
+ break;
+ case SIG('C', 'E'):
+ len = sizeof(struct SU_CE_s);
+ break;
+ case SIG('E', 'R'):
+ len = sizeof(struct SU_ER_s);
+ break;
+ case SIG('R', 'R'):
+ len = sizeof(struct RR_RR_s);
+ break;
+ case SIG('P', 'X'):
+ len = sizeof(struct RR_PX_s);
+ break;
+ case SIG('P', 'N'):
+ len = sizeof(struct RR_PN_s);
+ break;
+ case SIG('S', 'L'):
+ len = sizeof(struct RR_SL_s);
+ break;
+ case SIG('N', 'M'):
+ len = sizeof(struct RR_NM_s);
+ break;
+ case SIG('C', 'L'):
+ len = sizeof(struct RR_CL_s);
+ break;
+ case SIG('P', 'L'):
+ len = sizeof(struct RR_PL_s);
+ break;
+ case SIG('T', 'F'):
+ len = sizeof(struct RR_TF_s);
+ break;
+ case SIG('Z', 'F'):
+ len = sizeof(struct RR_ZF_s);
+ break;
+ default:
+ len = 0;
+ break;
+ }
+ len += offsetof(struct rock_ridge, u);
+ if (len > rs->len) {
+ printk(KERN_NOTICE "rock: directory entry would overflow "
+ "storage\n");
+ printk(KERN_NOTICE "rock: sig=0x%02x, size=%d, remaining=%d\n",
+ sig, len, rs->len);
+ return -EIO;
+ }
+ return 0;
+}
+
+/*
+ * return length of name field; 0: not found, -1: to be ignored
+ */
+int get_rock_ridge_filename(struct iso_directory_record *de,
+ char *retname, struct inode *inode)
+{
+ struct rock_state rs;
+ struct rock_ridge *rr;
+ int sig;
+ int retnamlen = 0;
+ int truncate = 0;
+ int ret = 0;
+
+ if (!ISOFS_SB(inode->i_sb)->s_rock)
+ return 0;
+ *retname = 0;
+
+ init_rock_state(&rs, inode);
+ setup_rock_ridge(de, inode, &rs);
+repeat:
+
+ while (rs.len > 2) { /* There may be one byte for padding somewhere */
+ rr = (struct rock_ridge *)rs.chr;
+ /*
+ * Ignore rock ridge info if rr->len is out of range, but
+ * don't return -EIO because that would make the file
+ * invisible.
+ */
+ if (rr->len < 3)
+ goto out; /* Something got screwed up here */
+ sig = isonum_721(rs.chr);
+ if (rock_check_overflow(&rs, sig))
+ goto eio;
+ rs.chr += rr->len;
+ rs.len -= rr->len;
+ /*
+ * As above, just ignore the rock ridge info if rr->len
+ * is bogus.
+ */
+ if (rs.len < 0)
+ goto out; /* Something got screwed up here */
+
+ switch (sig) {
+ case SIG('R', 'R'):
+ if ((rr->u.RR.flags[0] & RR_NM) == 0)
+ goto out;
+ break;
+ case SIG('S', 'P'):
+ if (check_sp(rr, inode))
+ goto out;
+ break;
+ case SIG('C', 'E'):
+ 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);
+ break;
+ case SIG('N', 'M'):
+ if (truncate)
+ break;
+ if (rr->len < 5)
+ break;
+ /*
+ * If the flags are 2 or 4, this indicates '.' or '..'.
+ * We don't want to do anything with this, because it
+ * screws up the code that calls us. We don't really
+ * care anyways, since we can just use the non-RR
+ * name.
+ */
+ if (rr->u.NM.flags & 6)
+ break;
+
+ if (rr->u.NM.flags & ~1) {
+ printk("Unsupported NM flag settings (%d)\n",
+ rr->u.NM.flags);
+ break;
+ }
+ if ((strlen(retname) + rr->len - 5) >= 254) {
+ truncate = 1;
+ break;
+ }
+ strncat(retname, rr->u.NM.name, rr->len - 5);
+ retnamlen += rr->len - 5;
+ break;
+ case SIG('R', 'E'):
+ kfree(rs.buffer);
+ return -1;
+ default:
+ break;
+ }
+ }
+ ret = rock_continue(&rs);
+ if (ret == 0)
+ goto repeat;
+ if (ret == 1)
+ return retnamlen; /* If 0, this file did not have a NM field */
+out:
+ kfree(rs.buffer);
+ return ret;
+eio:
+ ret = -EIO;
+ goto out;
+}
+
+#define RR_REGARD_XA 1
+#define RR_RELOC_DE 2
+
+static int
+parse_rock_ridge_inode_internal(struct iso_directory_record *de,
+ struct inode *inode, int flags)
+{
+ int symlink_len = 0;
+ int cnt, sig;
+ unsigned int reloc_block;
+ struct inode *reloc;
+ struct rock_ridge *rr;
+ int rootflag;
+ struct rock_state rs;
+ int ret = 0;
+
+ if (!ISOFS_SB(inode->i_sb)->s_rock)
+ return 0;
+
+ init_rock_state(&rs, inode);
+ setup_rock_ridge(de, inode, &rs);
+ if (flags & RR_REGARD_XA) {
+ rs.chr += 14;
+ rs.len -= 14;
+ if (rs.len < 0)
+ rs.len = 0;
+ }
+
+repeat:
+ while (rs.len > 2) { /* There may be one byte for padding somewhere */
+ rr = (struct rock_ridge *)rs.chr;
+ /*
+ * Ignore rock ridge info if rr->len is out of range, but
+ * don't return -EIO because that would make the file
+ * invisible.
+ */
+ if (rr->len < 3)
+ goto out; /* Something got screwed up here */
+ sig = isonum_721(rs.chr);
+ if (rock_check_overflow(&rs, sig))
+ goto eio;
+ rs.chr += rr->len;
+ rs.len -= rr->len;
+ /*
+ * As above, just ignore the rock ridge info if rr->len
+ * is bogus.
+ */
+ if (rs.len < 0)
+ goto out; /* Something got screwed up here */
+
+ switch (sig) {
+#ifndef CONFIG_ZISOFS /* No flag for SF or ZF */
+ case SIG('R', 'R'):
+ if ((rr->u.RR.flags[0] &
+ (RR_PX | RR_TF | RR_SL | RR_CL)) == 0)
+ goto out;
+ break;
+#endif
+ case SIG('S', 'P'):
+ if (check_sp(rr, inode))
+ goto out;
+ break;
+ case SIG('C', 'E'):
+ 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);
+ break;
+ case SIG('E', 'R'):
+ /* Invalid length of ER tag id? */
+ if (rr->u.ER.len_id + offsetof(struct rock_ridge, u.ER.data) > rr->len)
+ goto out;
+ ISOFS_SB(inode->i_sb)->s_rock = 1;
+ printk(KERN_DEBUG "ISO 9660 Extensions: ");
+ {
+ int p;
+ for (p = 0; p < rr->u.ER.len_id; p++)
+ printk("%c", rr->u.ER.data[p]);
+ }
+ printk("\n");
+ break;
+ case SIG('P', 'X'):
+ inode->i_mode = isonum_733(rr->u.PX.mode);
+ set_nlink(inode, isonum_733(rr->u.PX.n_links));
+ i_uid_write(inode, isonum_733(rr->u.PX.uid));
+ i_gid_write(inode, isonum_733(rr->u.PX.gid));
+ break;
+ case SIG('P', 'N'):
+ {
+ int high, low;
+ high = isonum_733(rr->u.PN.dev_high);
+ low = isonum_733(rr->u.PN.dev_low);
+ /*
+ * The Rock Ridge standard specifies that if
+ * sizeof(dev_t) <= 4, then the high field is
+ * unused, and the device number is completely
+ * stored in the low field. Some writers may
+ * ignore this subtlety,
+ * and as a result we test to see if the entire
+ * device number is
+ * stored in the low field, and use that.
+ */
+ if ((low & ~0xff) && high == 0) {
+ inode->i_rdev =
+ MKDEV(low >> 8, low & 0xff);
+ } else {
+ inode->i_rdev =
+ MKDEV(high, low);
+ }
+ }
+ break;
+ case SIG('T', 'F'):
+ /*
+ * Some RRIP writers incorrectly place ctime in the
+ * TF_CREATE field. Try to handle this correctly for
+ * either case.
+ */
+ /* Rock ridge never appears on a High Sierra disk */
+ cnt = 0;
+ if (rr->u.TF.flags & TF_CREATE) {
+ inode->i_ctime.tv_sec =
+ iso_date(rr->u.TF.times[cnt++].time,
+ 0);
+ inode->i_ctime.tv_nsec = 0;
+ }
+ if (rr->u.TF.flags & TF_MODIFY) {
+ inode->i_mtime.tv_sec =
+ iso_date(rr->u.TF.times[cnt++].time,
+ 0);
+ inode->i_mtime.tv_nsec = 0;
+ }
+ if (rr->u.TF.flags & TF_ACCESS) {
+ inode->i_atime.tv_sec =
+ iso_date(rr->u.TF.times[cnt++].time,
+ 0);
+ inode->i_atime.tv_nsec = 0;
+ }
+ if (rr->u.TF.flags & TF_ATTRIBUTES) {
+ inode->i_ctime.tv_sec =
+ iso_date(rr->u.TF.times[cnt++].time,
+ 0);
+ inode->i_ctime.tv_nsec = 0;
+ }
+ break;
+ case SIG('S', 'L'):
+ {
+ int slen;
+ struct SL_component *slp;
+ struct SL_component *oldslp;
+ slen = rr->len - 5;
+ slp = &rr->u.SL.link;
+ inode->i_size = symlink_len;
+ while (slen > 1) {
+ rootflag = 0;
+ switch (slp->flags & ~1) {
+ case 0:
+ inode->i_size +=
+ slp->len;
+ break;
+ case 2:
+ inode->i_size += 1;
+ break;
+ case 4:
+ inode->i_size += 2;
+ break;
+ case 8:
+ rootflag = 1;
+ inode->i_size += 1;
+ break;
+ default:
+ printk("Symlink component flag "
+ "not implemented\n");
+ }
+ slen -= slp->len + 2;
+ oldslp = slp;
+ slp = (struct SL_component *)
+ (((char *)slp) + slp->len + 2);
+
+ if (slen < 2) {
+ if (((rr->u.SL.
+ flags & 1) != 0)
+ &&
+ ((oldslp->
+ flags & 1) == 0))
+ inode->i_size +=
+ 1;
+ break;
+ }
+
+ /*
+ * If this component record isn't
+ * continued, then append a '/'.
+ */
+ if (!rootflag
+ && (oldslp->flags & 1) == 0)
+ inode->i_size += 1;
+ }
+ }
+ symlink_len = inode->i_size;
+ break;
+ case SIG('R', 'E'):
+ printk(KERN_WARNING "Attempt to read inode for "
+ "relocated directory\n");
+ goto out;
+ case SIG('C', 'L'):
+ if (flags & RR_RELOC_DE) {
+ printk(KERN_ERR
+ "ISOFS: Recursive directory relocation "
+ "is not supported\n");
+ goto eio;
+ }
+ reloc_block = isonum_733(rr->u.CL.location);
+ if (reloc_block == ISOFS_I(inode)->i_iget5_block &&
+ ISOFS_I(inode)->i_iget5_offset == 0) {
+ printk(KERN_ERR
+ "ISOFS: Directory relocation points to "
+ "itself\n");
+ goto eio;
+ }
+ ISOFS_I(inode)->i_first_extent = reloc_block;
+ reloc = isofs_iget_reloc(inode->i_sb, reloc_block, 0);
+ if (IS_ERR(reloc)) {
+ ret = PTR_ERR(reloc);
+ goto out;
+ }
+ inode->i_mode = reloc->i_mode;
+ set_nlink(inode, reloc->i_nlink);
+ inode->i_uid = reloc->i_uid;
+ inode->i_gid = reloc->i_gid;
+ inode->i_rdev = reloc->i_rdev;
+ inode->i_size = reloc->i_size;
+ inode->i_blocks = reloc->i_blocks;
+ inode->i_atime = reloc->i_atime;
+ inode->i_ctime = reloc->i_ctime;
+ inode->i_mtime = reloc->i_mtime;
+ iput(reloc);
+ break;
+#ifdef CONFIG_ZISOFS
+ case SIG('Z', 'F'): {
+ int algo;
+
+ if (ISOFS_SB(inode->i_sb)->s_nocompress)
+ break;
+ algo = isonum_721(rr->u.ZF.algorithm);
+ if (algo == SIG('p', 'z')) {
+ int block_shift =
+ isonum_711(&rr->u.ZF.parms[1]);
+ if (block_shift > 17) {
+ printk(KERN_WARNING "isofs: "
+ "Can't handle ZF block "
+ "size of 2^%d\n",
+ block_shift);
+ } else {
+ /*
+ * Note: we don't change
+ * i_blocks here
+ */
+ ISOFS_I(inode)->i_file_format =
+ isofs_file_compressed;
+ /*
+ * Parameters to compression
+ * algorithm (header size,
+ * block size)
+ */
+ ISOFS_I(inode)->i_format_parm[0] =
+ isonum_711(&rr->u.ZF.parms[0]);
+ ISOFS_I(inode)->i_format_parm[1] =
+ isonum_711(&rr->u.ZF.parms[1]);
+ inode->i_size =
+ isonum_733(rr->u.ZF.
+ real_size);
+ }
+ } else {
+ printk(KERN_WARNING
+ "isofs: Unknown ZF compression "
+ "algorithm: %c%c\n",
+ rr->u.ZF.algorithm[0],
+ rr->u.ZF.algorithm[1]);
+ }
+ break;
+ }
+#endif
+ default:
+ break;
+ }
+ }
+ ret = rock_continue(&rs);
+ if (ret == 0)
+ goto repeat;
+ if (ret == 1)
+ ret = 0;
+out:
+ kfree(rs.buffer);
+ 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 = kmap(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);
+ kunmap(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);
+ kunmap(page);
+ unlock_page(page);
+ return -EIO;
+}
+
+const struct address_space_operations isofs_symlink_aops = {
+ .readpage = rock_ridge_symlink_readpage
+};