cregit-Linux how code gets into the kernel

Release 4.18 fs/qnx6/dir.c

Directory: fs/qnx6
// SPDX-License-Identifier: GPL-2.0
/*
 * QNX6 file system, Linux implementation.
 *
 * Version : 1.0.0
 *
 * History :
 *
 * 01-02-2012 by Kai Bankett (chaosman@ontika.net) : first release.
 * 16-02-2012 pagemap extension by Al Viro
 *
 */

#include "qnx6.h"


static unsigned qnx6_lfile_checksum(char *name, unsigned size) { unsigned crc = 0; char *end = name + size; while (name < end) { crc = ((crc >> 1) + *(name++)) ^ ((crc & 0x00000001) ? 0x80000000 : 0); } return crc; }

Contributors

PersonTokensPropCommitsCommitProp
Kai Bankett65100.00%1100.00%
Total65100.00%1100.00%


static struct page *qnx6_get_page(struct inode *dir, unsigned long n) { struct address_space *mapping = dir->i_mapping; struct page *page = read_mapping_page(mapping, n, NULL); if (!IS_ERR(page)) kmap(page); return page; }

Contributors

PersonTokensPropCommitsCommitProp
Kai Bankett56100.00%1100.00%
Total56100.00%1100.00%


static unsigned last_entry(struct inode *inode, unsigned long page_nr) { unsigned long last_byte = inode->i_size; last_byte -= page_nr << PAGE_SHIFT; if (last_byte > PAGE_SIZE) last_byte = PAGE_SIZE; return last_byte / QNX6_DIR_ENTRY_SIZE; }

Contributors

PersonTokensPropCommitsCommitProp
Kai Bankett4193.18%150.00%
Kirill A. Shutemov36.82%150.00%
Total44100.00%2100.00%


static struct qnx6_long_filename *qnx6_longname(struct super_block *sb, struct qnx6_long_dir_entry *de, struct page **p) { struct qnx6_sb_info *sbi = QNX6_SB(sb); u32 s = fs32_to_cpu(sbi, de->de_long_inode); /* in block units */ u32 n = s >> (PAGE_SHIFT - sb->s_blocksize_bits); /* in pages */ /* within page */ u32 offs = (s << sb->s_blocksize_bits) & ~PAGE_MASK; struct address_space *mapping = sbi->longfile->i_mapping; struct page *page = read_mapping_page(mapping, n, NULL); if (IS_ERR(page)) return ERR_CAST(page); kmap(*p = page); return (struct qnx6_long_filename *)(page_address(page) + offs); }

Contributors

PersonTokensPropCommitsCommitProp
Kai Bankett13598.54%150.00%
Kirill A. Shutemov21.46%150.00%
Total137100.00%2100.00%


static int qnx6_dir_longfilename(struct inode *inode, struct qnx6_long_dir_entry *de, struct dir_context *ctx, unsigned de_inode) { struct qnx6_long_filename *lf; struct super_block *s = inode->i_sb; struct qnx6_sb_info *sbi = QNX6_SB(s); struct page *page; int lf_size; if (de->de_size != 0xff) { /* error - long filename entries always have size 0xff in direntry */ pr_err("invalid direntry size (%i).\n", de->de_size); return 0; } lf = qnx6_longname(s, de, &page); if (IS_ERR(lf)) { pr_err("Error reading longname\n"); return 0; } lf_size = fs16_to_cpu(sbi, lf->lf_size); if (lf_size > QNX6_LONG_NAME_MAX) { pr_debug("file %s\n", lf->lf_fname); pr_err("Filename too long (%i)\n", lf_size); qnx6_put_page(page); return 0; } /* calc & validate longfilename checksum mmi 3g filesystem does not have that checksum */ if (!test_opt(s, MMI_FS) && fs32_to_cpu(sbi, de->de_checksum) != qnx6_lfile_checksum(lf->lf_fname, lf_size)) pr_info("long filename checksum error.\n"); pr_debug("qnx6_readdir:%.*s inode:%u\n", lf_size, lf->lf_fname, de_inode); if (!dir_emit(ctx, lf->lf_fname, lf_size, de_inode, DT_UNKNOWN)) { qnx6_put_page(page); return 0; } qnx6_put_page(page); /* success */ return 1; }

Contributors

PersonTokensPropCommitsCommitProp
Kai Bankett21591.49%120.00%
Fabian Frederick145.96%360.00%
Al Viro62.55%120.00%
Total235100.00%5100.00%


static int qnx6_readdir(struct file *file, struct dir_context *ctx) { struct inode *inode = file_inode(file); struct super_block *s = inode->i_sb; struct qnx6_sb_info *sbi = QNX6_SB(s); loff_t pos = ctx->pos & ~(QNX6_DIR_ENTRY_SIZE - 1); unsigned long npages = dir_pages(inode); unsigned long n = pos >> PAGE_SHIFT; unsigned start = (pos & ~PAGE_MASK) / QNX6_DIR_ENTRY_SIZE; bool done = false; ctx->pos = pos; if (ctx->pos >= inode->i_size) return 0; for ( ; !done && n < npages; n++, start = 0) { struct page *page = qnx6_get_page(inode, n); int limit = last_entry(inode, n); struct qnx6_dir_entry *de; int i = start; if (IS_ERR(page)) { pr_err("%s(): read failed\n", __func__); ctx->pos = (n + 1) << PAGE_SHIFT; return PTR_ERR(page); } de = ((struct qnx6_dir_entry *)page_address(page)) + start; for (; i < limit; i++, de++, ctx->pos += QNX6_DIR_ENTRY_SIZE) { int size = de->de_size; u32 no_inode = fs32_to_cpu(sbi, de->de_inode); if (!no_inode || !size) continue; if (size > QNX6_SHORT_NAME_MAX) { /* long filename detected get the filename from long filename structure / block */ if (!qnx6_dir_longfilename(inode, (struct qnx6_long_dir_entry *)de, ctx, no_inode)) { done = true; break; } } else { pr_debug("%s():%.*s inode:%u\n", __func__, size, de->de_fname, no_inode); if (!dir_emit(ctx, de->de_fname, size, no_inode, DT_UNKNOWN)) { done = true; break; } } } qnx6_put_page(page); } return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Kai Bankett30788.22%112.50%
Al Viro277.76%337.50%
Fabian Frederick113.16%337.50%
Kirill A. Shutemov30.86%112.50%
Total348100.00%8100.00%

/* * check if the long filename is correct. */
static unsigned qnx6_long_match(int len, const char *name, struct qnx6_long_dir_entry *de, struct inode *dir) { struct super_block *s = dir->i_sb; struct qnx6_sb_info *sbi = QNX6_SB(s); struct page *page; int thislen; struct qnx6_long_filename *lf = qnx6_longname(s, de, &page); if (IS_ERR(lf)) return 0; thislen = fs16_to_cpu(sbi, lf->lf_size); if (len != thislen) { qnx6_put_page(page); return 0; } if (memcmp(name, lf->lf_fname, len) == 0) { qnx6_put_page(page); return fs32_to_cpu(sbi, de->de_inode); } qnx6_put_page(page); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Kai Bankett143100.00%1100.00%
Total143100.00%1100.00%

/* * check if the filename is correct. */
static unsigned qnx6_match(struct super_block *s, int len, const char *name, struct qnx6_dir_entry *de) { struct qnx6_sb_info *sbi = QNX6_SB(s); if (memcmp(name, de->de_fname, len) == 0) return fs32_to_cpu(sbi, de->de_inode); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Kai Bankett62100.00%1100.00%
Total62100.00%1100.00%


unsigned qnx6_find_entry(int len, struct inode *dir, const char *name, struct page **res_page) { struct super_block *s = dir->i_sb; struct qnx6_inode_info *ei = QNX6_I(dir); struct page *page = NULL; unsigned long start, n; unsigned long npages = dir_pages(dir); unsigned ino; struct qnx6_dir_entry *de; struct qnx6_long_dir_entry *lde; *res_page = NULL; if (npages == 0) return 0; start = ei->i_dir_start_lookup; if (start >= npages) start = 0; n = start; do { page = qnx6_get_page(dir, n); if (!IS_ERR(page)) { int limit = last_entry(dir, n); int i; de = (struct qnx6_dir_entry *)page_address(page); for (i = 0; i < limit; i++, de++) { if (len <= QNX6_SHORT_NAME_MAX) { /* short filename */ if (len != de->de_size) continue; ino = qnx6_match(s, len, name, de); if (ino) goto found; } else if (de->de_size == 0xff) { /* deal with long filename */ lde = (struct qnx6_long_dir_entry *)de; ino = qnx6_long_match(len, name, lde, dir); if (ino) goto found; } else pr_err("undefined filename size in inode.\n"); } qnx6_put_page(page); } if (++n >= npages) n = 0; } while (n != start); return 0; found: *res_page = page; ei->i_dir_start_lookup = n; return ino; }

Contributors

PersonTokensPropCommitsCommitProp
Kai Bankett30299.34%133.33%
Fabian Frederick20.66%266.67%
Total304100.00%3100.00%

const struct file_operations qnx6_dir_operations = { .llseek = generic_file_llseek, .read = generic_read_dir, .iterate_shared = qnx6_readdir, .fsync = generic_file_fsync, }; const struct inode_operations qnx6_dir_inode_operations = { .lookup = qnx6_lookup, };

Overall Contributors

PersonTokensPropCommitsCommitProp
Kai Bankett137095.14%110.00%
Al Viro342.36%440.00%
Fabian Frederick271.88%330.00%
Kirill A. Shutemov80.56%110.00%
Greg Kroah-Hartman10.07%110.00%
Total1440100.00%10100.00%
Directory: fs/qnx6
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