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author | Srikant Patnaik | 2015-01-11 12:28:04 +0530 |
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committer | Srikant Patnaik | 2015-01-11 12:28:04 +0530 |
commit | 871480933a1c28f8a9fed4c4d34d06c439a7a422 (patch) | |
tree | 8718f573808810c2a1e8cb8fb6ac469093ca2784 /fs/bfs/dir.c | |
parent | 9d40ac5867b9aefe0722bc1f110b965ff294d30d (diff) | |
download | FOSSEE-netbook-kernel-source-871480933a1c28f8a9fed4c4d34d06c439a7a422.tar.gz FOSSEE-netbook-kernel-source-871480933a1c28f8a9fed4c4d34d06c439a7a422.tar.bz2 FOSSEE-netbook-kernel-source-871480933a1c28f8a9fed4c4d34d06c439a7a422.zip |
Moved, renamed, and deleted files
The original directory structure was scattered and unorganized.
Changes are basically to make it look like kernel structure.
Diffstat (limited to 'fs/bfs/dir.c')
-rw-r--r-- | fs/bfs/dir.c | 374 |
1 files changed, 374 insertions, 0 deletions
diff --git a/fs/bfs/dir.c b/fs/bfs/dir.c new file mode 100644 index 00000000..d12c7966 --- /dev/null +++ b/fs/bfs/dir.c @@ -0,0 +1,374 @@ +/* + * fs/bfs/dir.c + * BFS directory operations. + * Copyright (C) 1999,2000 Tigran Aivazian <tigran@veritas.com> + * Made endianness-clean by Andrew Stribblehill <ads@wompom.org> 2005 + */ + +#include <linux/time.h> +#include <linux/string.h> +#include <linux/fs.h> +#include <linux/buffer_head.h> +#include <linux/sched.h> +#include "bfs.h" + +#undef DEBUG + +#ifdef DEBUG +#define dprintf(x...) printf(x) +#else +#define dprintf(x...) +#endif + +static int bfs_add_entry(struct inode *dir, const unsigned char *name, + int namelen, int ino); +static struct buffer_head *bfs_find_entry(struct inode *dir, + const unsigned char *name, int namelen, + struct bfs_dirent **res_dir); + +static int bfs_readdir(struct file *f, void *dirent, filldir_t filldir) +{ + struct inode *dir = f->f_path.dentry->d_inode; + struct buffer_head *bh; + struct bfs_dirent *de; + struct bfs_sb_info *info = BFS_SB(dir->i_sb); + unsigned int offset; + int block; + + mutex_lock(&info->bfs_lock); + + if (f->f_pos & (BFS_DIRENT_SIZE - 1)) { + printf("Bad f_pos=%08lx for %s:%08lx\n", + (unsigned long)f->f_pos, + dir->i_sb->s_id, dir->i_ino); + mutex_unlock(&info->bfs_lock); + return -EBADF; + } + + while (f->f_pos < dir->i_size) { + offset = f->f_pos & (BFS_BSIZE - 1); + block = BFS_I(dir)->i_sblock + (f->f_pos >> BFS_BSIZE_BITS); + bh = sb_bread(dir->i_sb, block); + if (!bh) { + f->f_pos += BFS_BSIZE - offset; + continue; + } + do { + de = (struct bfs_dirent *)(bh->b_data + offset); + if (de->ino) { + int size = strnlen(de->name, BFS_NAMELEN); + if (filldir(dirent, de->name, size, f->f_pos, + le16_to_cpu(de->ino), + DT_UNKNOWN) < 0) { + brelse(bh); + mutex_unlock(&info->bfs_lock); + return 0; + } + } + offset += BFS_DIRENT_SIZE; + f->f_pos += BFS_DIRENT_SIZE; + } while ((offset < BFS_BSIZE) && (f->f_pos < dir->i_size)); + brelse(bh); + } + + mutex_unlock(&info->bfs_lock); + return 0; +} + +const struct file_operations bfs_dir_operations = { + .read = generic_read_dir, + .readdir = bfs_readdir, + .fsync = generic_file_fsync, + .llseek = generic_file_llseek, +}; + +extern void dump_imap(const char *, struct super_block *); + +static int bfs_create(struct inode *dir, struct dentry *dentry, umode_t mode, + struct nameidata *nd) +{ + int err; + struct inode *inode; + struct super_block *s = dir->i_sb; + struct bfs_sb_info *info = BFS_SB(s); + unsigned long ino; + + inode = new_inode(s); + if (!inode) + return -ENOSPC; + mutex_lock(&info->bfs_lock); + ino = find_first_zero_bit(info->si_imap, info->si_lasti + 1); + if (ino > info->si_lasti) { + mutex_unlock(&info->bfs_lock); + iput(inode); + return -ENOSPC; + } + set_bit(ino, info->si_imap); + info->si_freei--; + inode_init_owner(inode, dir, mode); + inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME_SEC; + inode->i_blocks = 0; + inode->i_op = &bfs_file_inops; + inode->i_fop = &bfs_file_operations; + inode->i_mapping->a_ops = &bfs_aops; + inode->i_ino = ino; + BFS_I(inode)->i_dsk_ino = ino; + BFS_I(inode)->i_sblock = 0; + BFS_I(inode)->i_eblock = 0; + insert_inode_hash(inode); + mark_inode_dirty(inode); + dump_imap("create", s); + + err = bfs_add_entry(dir, dentry->d_name.name, dentry->d_name.len, + inode->i_ino); + if (err) { + inode_dec_link_count(inode); + mutex_unlock(&info->bfs_lock); + iput(inode); + return err; + } + mutex_unlock(&info->bfs_lock); + d_instantiate(dentry, inode); + return 0; +} + +static struct dentry *bfs_lookup(struct inode *dir, struct dentry *dentry, + struct nameidata *nd) +{ + struct inode *inode = NULL; + struct buffer_head *bh; + struct bfs_dirent *de; + struct bfs_sb_info *info = BFS_SB(dir->i_sb); + + if (dentry->d_name.len > BFS_NAMELEN) + return ERR_PTR(-ENAMETOOLONG); + + mutex_lock(&info->bfs_lock); + bh = bfs_find_entry(dir, dentry->d_name.name, dentry->d_name.len, &de); + if (bh) { + unsigned long ino = (unsigned long)le16_to_cpu(de->ino); + brelse(bh); + inode = bfs_iget(dir->i_sb, ino); + if (IS_ERR(inode)) { + mutex_unlock(&info->bfs_lock); + return ERR_CAST(inode); + } + } + mutex_unlock(&info->bfs_lock); + d_add(dentry, inode); + return NULL; +} + +static int bfs_link(struct dentry *old, struct inode *dir, + struct dentry *new) +{ + struct inode *inode = old->d_inode; + struct bfs_sb_info *info = BFS_SB(inode->i_sb); + int err; + + mutex_lock(&info->bfs_lock); + err = bfs_add_entry(dir, new->d_name.name, new->d_name.len, + inode->i_ino); + if (err) { + mutex_unlock(&info->bfs_lock); + return err; + } + inc_nlink(inode); + inode->i_ctime = CURRENT_TIME_SEC; + mark_inode_dirty(inode); + ihold(inode); + d_instantiate(new, inode); + mutex_unlock(&info->bfs_lock); + return 0; +} + +static int bfs_unlink(struct inode *dir, struct dentry *dentry) +{ + int error = -ENOENT; + struct inode *inode = dentry->d_inode; + struct buffer_head *bh; + struct bfs_dirent *de; + struct bfs_sb_info *info = BFS_SB(inode->i_sb); + + mutex_lock(&info->bfs_lock); + bh = bfs_find_entry(dir, dentry->d_name.name, dentry->d_name.len, &de); + if (!bh || (le16_to_cpu(de->ino) != inode->i_ino)) + goto out_brelse; + + if (!inode->i_nlink) { + printf("unlinking non-existent file %s:%lu (nlink=%d)\n", + inode->i_sb->s_id, inode->i_ino, + inode->i_nlink); + set_nlink(inode, 1); + } + de->ino = 0; + mark_buffer_dirty_inode(bh, dir); + dir->i_ctime = dir->i_mtime = CURRENT_TIME_SEC; + mark_inode_dirty(dir); + inode->i_ctime = dir->i_ctime; + inode_dec_link_count(inode); + error = 0; + +out_brelse: + brelse(bh); + mutex_unlock(&info->bfs_lock); + return error; +} + +static int bfs_rename(struct inode *old_dir, struct dentry *old_dentry, + struct inode *new_dir, struct dentry *new_dentry) +{ + struct inode *old_inode, *new_inode; + struct buffer_head *old_bh, *new_bh; + struct bfs_dirent *old_de, *new_de; + struct bfs_sb_info *info; + int error = -ENOENT; + + old_bh = new_bh = NULL; + old_inode = old_dentry->d_inode; + if (S_ISDIR(old_inode->i_mode)) + return -EINVAL; + + info = BFS_SB(old_inode->i_sb); + + mutex_lock(&info->bfs_lock); + old_bh = bfs_find_entry(old_dir, + old_dentry->d_name.name, + old_dentry->d_name.len, &old_de); + + if (!old_bh || (le16_to_cpu(old_de->ino) != old_inode->i_ino)) + goto end_rename; + + error = -EPERM; + new_inode = new_dentry->d_inode; + new_bh = bfs_find_entry(new_dir, + new_dentry->d_name.name, + new_dentry->d_name.len, &new_de); + + if (new_bh && !new_inode) { + brelse(new_bh); + new_bh = NULL; + } + if (!new_bh) { + error = bfs_add_entry(new_dir, + new_dentry->d_name.name, + new_dentry->d_name.len, + old_inode->i_ino); + if (error) + goto end_rename; + } + old_de->ino = 0; + old_dir->i_ctime = old_dir->i_mtime = CURRENT_TIME_SEC; + mark_inode_dirty(old_dir); + if (new_inode) { + new_inode->i_ctime = CURRENT_TIME_SEC; + inode_dec_link_count(new_inode); + } + mark_buffer_dirty_inode(old_bh, old_dir); + error = 0; + +end_rename: + mutex_unlock(&info->bfs_lock); + brelse(old_bh); + brelse(new_bh); + return error; +} + +const struct inode_operations bfs_dir_inops = { + .create = bfs_create, + .lookup = bfs_lookup, + .link = bfs_link, + .unlink = bfs_unlink, + .rename = bfs_rename, +}; + +static int bfs_add_entry(struct inode *dir, const unsigned char *name, + int namelen, int ino) +{ + struct buffer_head *bh; + struct bfs_dirent *de; + int block, sblock, eblock, off, pos; + int i; + + dprintf("name=%s, namelen=%d\n", name, namelen); + + if (!namelen) + return -ENOENT; + if (namelen > BFS_NAMELEN) + return -ENAMETOOLONG; + + sblock = BFS_I(dir)->i_sblock; + eblock = BFS_I(dir)->i_eblock; + for (block = sblock; block <= eblock; block++) { + bh = sb_bread(dir->i_sb, block); + if (!bh) + return -ENOSPC; + for (off = 0; off < BFS_BSIZE; off += BFS_DIRENT_SIZE) { + de = (struct bfs_dirent *)(bh->b_data + off); + if (!de->ino) { + pos = (block - sblock) * BFS_BSIZE + off; + if (pos >= dir->i_size) { + dir->i_size += BFS_DIRENT_SIZE; + dir->i_ctime = CURRENT_TIME_SEC; + } + dir->i_mtime = CURRENT_TIME_SEC; + mark_inode_dirty(dir); + de->ino = cpu_to_le16((u16)ino); + for (i = 0; i < BFS_NAMELEN; i++) + de->name[i] = + (i < namelen) ? name[i] : 0; + mark_buffer_dirty_inode(bh, dir); + brelse(bh); + return 0; + } + } + brelse(bh); + } + return -ENOSPC; +} + +static inline int bfs_namecmp(int len, const unsigned char *name, + const char *buffer) +{ + if ((len < BFS_NAMELEN) && buffer[len]) + return 0; + return !memcmp(name, buffer, len); +} + +static struct buffer_head *bfs_find_entry(struct inode *dir, + const unsigned char *name, int namelen, + struct bfs_dirent **res_dir) +{ + unsigned long block = 0, offset = 0; + struct buffer_head *bh = NULL; + struct bfs_dirent *de; + + *res_dir = NULL; + if (namelen > BFS_NAMELEN) + return NULL; + + while (block * BFS_BSIZE + offset < dir->i_size) { + if (!bh) { + bh = sb_bread(dir->i_sb, BFS_I(dir)->i_sblock + block); + if (!bh) { + block++; + continue; + } + } + de = (struct bfs_dirent *)(bh->b_data + offset); + offset += BFS_DIRENT_SIZE; + if (le16_to_cpu(de->ino) && + bfs_namecmp(namelen, name, de->name)) { + *res_dir = de; + return bh; + } + if (offset < bh->b_size) + continue; + brelse(bh); + bh = NULL; + offset = 0; + block++; + } + brelse(bh); + return NULL; +} |