[PATCH] rock: remove MAYBE_CONTINUE
[safe/jmp/linux-2.6] / fs / isofs / rock.c
index aafe356..efefbcc 100644 (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;
+       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.
@@ -38,82 +48,96 @@ static int check_sp(struct rock_ridge *rr, struct inode *inode)
 }
 
 static void setup_rock_ridge(struct iso_directory_record *de,
-                       struct inode *inode, unsigned char **chr, int *len)
+                       struct inode *inode, struct rock_state *rs)
 {
-       *len = sizeof(struct iso_directory_record) + de->name_len[0];
-       if (*len & 1)
-               (*len)++;
-       *chr = (unsigned char *)de + *len;
-       *len = *((unsigned char *)de) - *len;
-       if (*len < 0)
-               *len = 0;
+       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) {
-               *len -= ISOFS_SB(inode->i_sb)->s_rock_offset;
-               *chr += ISOFS_SB(inode->i_sb)->s_rock_offset;
-               if (*len < 0)
-                       *len = 0;
+               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;
        }
 }
 
-#define MAYBE_CONTINUE(LABEL,DEV) \
-  {if (buffer) { kfree(buffer); buffer = NULL; } \
-  if (cont_extent){ \
-    int block, offset, offset1; \
-    struct buffer_head * pbh; \
-    buffer = kmalloc(cont_size,GFP_KERNEL); \
-    if (!buffer) goto out; \
-    block = cont_extent; \
-    offset = cont_offset; \
-    offset1 = 0; \
-    pbh = sb_bread(DEV->i_sb, block); \
-    if(pbh){       \
-      if (offset > pbh->b_size || offset + cont_size > pbh->b_size){   \
-       brelse(pbh); \
-       goto out; \
-      } \
-      memcpy(buffer + offset1, pbh->b_data + offset, cont_size - offset1); \
-      brelse(pbh); \
-      chr = (unsigned char *) buffer; \
-      len = cont_size; \
-      cont_extent = 0; \
-      cont_size = 0; \
-      cont_offset = 0; \
-      goto LABEL; \
-    }    \
-    printk("Unable to read rock-ridge attributes\n");    \
-  }}
+static void init_rock_state(struct rock_state *rs, struct inode *inode)
+{
+       memset(rs, 0, sizeof(*rs));
+       rs->inode = inode;
+}
+
+/*
+ * 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;
+
+       kfree(rs->buffer);
+       rs->buffer = NULL;
+       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;
+               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;
+}
 
 /* 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)
 {
-       int len;
-       unsigned char *chr;
-       int cont_extent = 0;
-       int cont_offset = 0;
-       int cont_size = 0;
-       void *buffer = NULL;
+       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;
 
-       setup_rock_ridge(de, inode, &chr, &len);
+       init_rock_state(&rs, inode);
+       setup_rock_ridge(de, inode, &rs);
 repeat:
 
-       while (len > 2) { /* There may be one byte for padding somewhere */
-               rr = (struct rock_ridge *)chr;
+       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(chr);
-               chr += rr->len;
-               len -= rr->len;
-               if (len < 0)
+               sig = isonum_721(rs.chr);
+               rs.chr += rr->len;
+               rs.len -= rr->len;
+               if (rs.len < 0)
                        goto out;       /* corrupted isofs */
 
                switch (sig) {
@@ -126,9 +150,9 @@ repeat:
                                goto out;
                        break;
                case SIG('C', 'E'):
-                       cont_extent = isonum_733(rr->u.CE.extent);
-                       cont_offset = isonum_733(rr->u.CE.offset);
-                       cont_size = isonum_733(rr->u.CE.size);
+                       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)
@@ -158,58 +182,55 @@ repeat:
                        retnamlen += rr->len - 5;
                        break;
                case SIG('R', 'E'):
-                       if (buffer)
-                               kfree(buffer);
+                       kfree(rs.buffer);
                        return -1;
                default:
                        break;
                }
        }
-       MAYBE_CONTINUE(repeat, inode);
-       kfree(buffer);
-       return retnamlen;       /* If 0, this file did not have a NM field */
+       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:
-       if (buffer)
-               kfree(buffer);
-       return 0;
+       kfree(rs.buffer);
+       return ret;
 }
 
 static int
 parse_rock_ridge_inode_internal(struct iso_directory_record *de,
                                struct inode *inode, int regard_xa)
 {
-       int len;
-       unsigned char *chr;
        int symlink_len = 0;
        int cnt, sig;
        struct inode *reloc;
        struct rock_ridge *rr;
        int rootflag;
-       int cont_extent = 0;
-       int cont_offset = 0;
-       int cont_size = 0;
-       void *buffer = NULL;
+       struct rock_state rs;
+       int ret = 0;
 
        if (!ISOFS_SB(inode->i_sb)->s_rock)
                return 0;
 
-       setup_rock_ridge(de, inode, &chr, &len);
+       init_rock_state(&rs, inode);
+       setup_rock_ridge(de, inode, &rs);
        if (regard_xa) {
-               chr += 14;
-               len -= 14;
-               if (len < 0)
-                       len = 0;
+               rs.chr += 14;
+               rs.len -= 14;
+               if (rs.len < 0)
+                       rs.len = 0;
        }
 
 repeat:
-       while (len > 2) { /* There may be one byte for padding somewhere */
-               rr = (struct rock_ridge *)chr;
+       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(chr);
-               chr += rr->len;
-               len -= rr->len;
-               if (len < 0)
+               sig = isonum_721(rs.chr);
+               rs.chr += rr->len;
+               rs.len -= rr->len;
+               if (rs.len < 0)
                        goto out;       /* corrupted isofs */
 
                switch (sig) {
@@ -225,9 +246,9 @@ repeat:
                                goto out;
                        break;
                case SIG('C', 'E'):
-                       cont_extent = isonum_733(rr->u.CE.extent);
-                       cont_offset = isonum_733(rr->u.CE.offset);
-                       cont_size = isonum_733(rr->u.CE.size);
+                       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'):
                        ISOFS_SB(inode->i_sb)->s_rock = 1;
@@ -433,11 +454,14 @@ repeat:
                        break;
                }
        }
-       MAYBE_CONTINUE(repeat, inode);
+       ret = rock_continue(&rs);
+       if (ret == 0)
+               goto repeat;
+       if (ret == 1)
+               ret = 0;
 out:
-       if (buffer)
-               kfree(buffer);
-       return 0;
+       kfree(rs.buffer);
+       return ret;
 }
 
 static char *get_symlink_chunk(char *rpnt, struct rock_ridge *rr, char *plimit)
@@ -533,19 +557,16 @@ static int rock_ridge_symlink_readpage(struct file *file, struct page *page)
        char *rpnt = link;
        unsigned char *pnt;
        struct iso_directory_record *raw_de;
-       int cont_extent = 0;
-       int cont_offset = 0;
-       int cont_size = 0;
-       void *buffer = NULL;
        unsigned long block, offset;
        int sig;
-       int len;
-       unsigned char *chr;
        struct rock_ridge *rr;
+       struct rock_state rs;
+       int ret;
 
        if (!ISOFS_SB(inode->i_sb)->s_rock)
                goto error;
 
+       init_rock_state(&rs, inode);
        block = ei->i_iget5_block;
        lock_kernel();
        bh = sb_bread(inode->i_sb, block);
@@ -566,17 +587,17 @@ static int rock_ridge_symlink_readpage(struct file *file, struct page *page)
        /* Now test for possible Rock Ridge extensions which will override
           some of these numbers in the inode structure. */
 
-       setup_rock_ridge(raw_de, inode, &chr, &len);
+       setup_rock_ridge(raw_de, inode, &rs);
 
 repeat:
-       while (len > 2) { /* There may be one byte for padding somewhere */
-               rr = (struct rock_ridge *)chr;
+       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(chr);
-               chr += rr->len;
-               len -= rr->len;
-               if (len < 0)
+               sig = isonum_721(rs.chr);
+               rs.chr += rr->len;
+               rs.len -= rr->len;
+               if (rs.len < 0)
                        goto out;       /* corrupted isofs */
 
                switch (sig) {
@@ -596,15 +617,18 @@ repeat:
                        break;
                case SIG('C', 'E'):
                        /* This tells is if there is a continuation record */
-                       cont_extent = isonum_733(rr->u.CE.extent);
-                       cont_offset = isonum_733(rr->u.CE.offset);
-                       cont_size = isonum_733(rr->u.CE.size);
+                       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;
                }
        }
-       MAYBE_CONTINUE(repeat, inode);
-       kfree(buffer);
+       ret = rock_continue(&rs);
+       if (ret == 0)
+               goto repeat;
+       if (ret < 0)
+               goto fail;
 
        if (rpnt == link)
                goto fail;
@@ -618,8 +642,7 @@ repeat:
 
        /* error exit from macro */
 out:
-       if (buffer)
-               kfree(buffer);
+       kfree(rs.buffer);
        goto fail;
 out_noread:
        printk("unable to read i-node block");