cregit-Linux how code gets into the kernel

Release 4.10 fs/qnx6/super_mmi.c

Directory: fs/qnx6
/*
 * QNX6 file system, Linux implementation.
 *
 * Version : 1.0.0
 *
 * History :
 *
 * 01-02-2012 by Kai Bankett (chaosman@ontika.net) : first release.
 *
 */

#include <linux/buffer_head.h>
#include <linux/slab.h>
#include <linux/crc32.h>
#include "qnx6.h"


static void qnx6_mmi_copy_sb(struct qnx6_super_block *qsb, struct qnx6_mmi_super_block *sb) { qsb->sb_magic = sb->sb_magic; qsb->sb_checksum = sb->sb_checksum; qsb->sb_serial = sb->sb_serial; qsb->sb_blocksize = sb->sb_blocksize; qsb->sb_num_inodes = sb->sb_num_inodes; qsb->sb_free_inodes = sb->sb_free_inodes; qsb->sb_num_blocks = sb->sb_num_blocks; qsb->sb_free_blocks = sb->sb_free_blocks; /* the rest of the superblock is the same */ memcpy(&qsb->Inode, &sb->Inode, sizeof(sb->Inode)); memcpy(&qsb->Bitmap, &sb->Bitmap, sizeof(sb->Bitmap)); memcpy(&qsb->Longfile, &sb->Longfile, sizeof(sb->Longfile)); }

Contributors

PersonTokensPropCommitsCommitProp
kai bankettkai bankett141100.00%1100.00%
Total141100.00%1100.00%


struct qnx6_super_block *qnx6_mmi_fill_super(struct super_block *s, int silent) { struct buffer_head *bh1, *bh2 = NULL; struct qnx6_mmi_super_block *sb1, *sb2; struct qnx6_super_block *qsb = NULL; struct qnx6_sb_info *sbi; __u64 offset; /* Check the superblock signatures start with the first superblock */ bh1 = sb_bread(s, 0); if (!bh1) { pr_err("Unable to read first mmi superblock\n"); return NULL; } sb1 = (struct qnx6_mmi_super_block *)bh1->b_data; sbi = QNX6_SB(s); if (fs32_to_cpu(sbi, sb1->sb_magic) != QNX6_SUPER_MAGIC) { if (!silent) { pr_err("wrong signature (magic) in superblock #1.\n"); goto out; } } /* checksum check - start at byte 8 and end at byte 512 */ if (fs32_to_cpu(sbi, sb1->sb_checksum) != crc32_be(0, (char *)(bh1->b_data + 8), 504)) { pr_err("superblock #1 checksum error\n"); goto out; } /* calculate second superblock blocknumber */ offset = fs32_to_cpu(sbi, sb1->sb_num_blocks) + QNX6_SUPERBLOCK_AREA / fs32_to_cpu(sbi, sb1->sb_blocksize); /* set new blocksize */ if (!sb_set_blocksize(s, fs32_to_cpu(sbi, sb1->sb_blocksize))) { pr_err("unable to set blocksize\n"); goto out; } /* blocksize invalidates bh - pull it back in */ brelse(bh1); bh1 = sb_bread(s, 0); if (!bh1) goto out; sb1 = (struct qnx6_mmi_super_block *)bh1->b_data; /* read second superblock */ bh2 = sb_bread(s, offset); if (!bh2) { pr_err("unable to read the second superblock\n"); goto out; } sb2 = (struct qnx6_mmi_super_block *)bh2->b_data; if (fs32_to_cpu(sbi, sb2->sb_magic) != QNX6_SUPER_MAGIC) { if (!silent) pr_err("wrong signature (magic) in superblock #2.\n"); goto out; } /* checksum check - start at byte 8 and end at byte 512 */ if (fs32_to_cpu(sbi, sb2->sb_checksum) != crc32_be(0, (char *)(bh2->b_data + 8), 504)) { pr_err("superblock #1 checksum error\n"); goto out; } qsb = kmalloc(sizeof(*qsb), GFP_KERNEL); if (!qsb) { pr_err("unable to allocate memory.\n"); goto out; } if (fs64_to_cpu(sbi, sb1->sb_serial) > fs64_to_cpu(sbi, sb2->sb_serial)) { /* superblock #1 active */ qnx6_mmi_copy_sb(qsb, sb1); #ifdef CONFIG_QNX6FS_DEBUG qnx6_superblock_debug(qsb, s); #endif memcpy(bh1->b_data, qsb, sizeof(struct qnx6_super_block)); sbi->sb_buf = bh1; sbi->sb = (struct qnx6_super_block *)bh1->b_data; brelse(bh2); pr_info("superblock #1 active\n"); } else { /* superblock #2 active */ qnx6_mmi_copy_sb(qsb, sb2); #ifdef CONFIG_QNX6FS_DEBUG qnx6_superblock_debug(qsb, s); #endif memcpy(bh2->b_data, qsb, sizeof(struct qnx6_super_block)); sbi->sb_buf = bh2; sbi->sb = (struct qnx6_super_block *)bh2->b_data; brelse(bh1); pr_info("superblock #2 active\n"); } kfree(qsb); /* offset for mmi_fs is just SUPERBLOCK_AREA bytes */ sbi->s_blks_off = QNX6_SUPERBLOCK_AREA / s->s_blocksize; /* success */ return sbi->sb; out: if (bh1 != NULL) brelse(bh1); if (bh2 != NULL) brelse(bh2); return NULL; }

Contributors

PersonTokensPropCommitsCommitProp
kai bankettkai bankett56296.56%133.33%
fabian frederickfabian frederick203.44%266.67%
Total582100.00%3100.00%


Overall Contributors

PersonTokensPropCommitsCommitProp
kai bankettkai bankett71697.28%133.33%
fabian frederickfabian frederick202.72%266.67%
Total736100.00%3100.00%
Directory: fs/qnx6
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