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author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/ext2/namei.c | |
download | linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.bz2 |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'fs/ext2/namei.c')
-rw-r--r-- | fs/ext2/namei.c | 418 |
1 files changed, 418 insertions, 0 deletions
diff --git a/fs/ext2/namei.c b/fs/ext2/namei.c new file mode 100644 index 000000000000..3176b3d3ffa8 --- /dev/null +++ b/fs/ext2/namei.c @@ -0,0 +1,418 @@ +/* + * linux/fs/ext2/namei.c + * + * Rewrite to pagecache. Almost all code had been changed, so blame me + * if the things go wrong. Please, send bug reports to + * viro@parcelfarce.linux.theplanet.co.uk + * + * Stuff here is basically a glue between the VFS and generic UNIXish + * filesystem that keeps everything in pagecache. All knowledge of the + * directory layout is in fs/ext2/dir.c - it turned out to be easily separatable + * and it's easier to debug that way. In principle we might want to + * generalize that a bit and turn it into a library. Or not. + * + * The only non-static object here is ext2_dir_inode_operations. + * + * TODO: get rid of kmap() use, add readahead. + * + * Copyright (C) 1992, 1993, 1994, 1995 + * Remy Card (card@masi.ibp.fr) + * Laboratoire MASI - Institut Blaise Pascal + * Universite Pierre et Marie Curie (Paris VI) + * + * from + * + * linux/fs/minix/namei.c + * + * Copyright (C) 1991, 1992 Linus Torvalds + * + * Big-endian to little-endian byte-swapping/bitmaps by + * David S. Miller (davem@caip.rutgers.edu), 1995 + */ + +#include <linux/pagemap.h> +#include "ext2.h" +#include "xattr.h" +#include "acl.h" + +/* + * Couple of helper functions - make the code slightly cleaner. + */ + +static inline void ext2_inc_count(struct inode *inode) +{ + inode->i_nlink++; + mark_inode_dirty(inode); +} + +static inline void ext2_dec_count(struct inode *inode) +{ + inode->i_nlink--; + mark_inode_dirty(inode); +} + +static inline int ext2_add_nondir(struct dentry *dentry, struct inode *inode) +{ + int err = ext2_add_link(dentry, inode); + if (!err) { + d_instantiate(dentry, inode); + return 0; + } + ext2_dec_count(inode); + iput(inode); + return err; +} + +/* + * Methods themselves. + */ + +static struct dentry *ext2_lookup(struct inode * dir, struct dentry *dentry, struct nameidata *nd) +{ + struct inode * inode; + ino_t ino; + + if (dentry->d_name.len > EXT2_NAME_LEN) + return ERR_PTR(-ENAMETOOLONG); + + ino = ext2_inode_by_name(dir, dentry); + inode = NULL; + if (ino) { + inode = iget(dir->i_sb, ino); + if (!inode) + return ERR_PTR(-EACCES); + } + if (inode) + return d_splice_alias(inode, dentry); + d_add(dentry, inode); + return NULL; +} + +struct dentry *ext2_get_parent(struct dentry *child) +{ + unsigned long ino; + struct dentry *parent; + struct inode *inode; + struct dentry dotdot; + + dotdot.d_name.name = ".."; + dotdot.d_name.len = 2; + + ino = ext2_inode_by_name(child->d_inode, &dotdot); + if (!ino) + return ERR_PTR(-ENOENT); + inode = iget(child->d_inode->i_sb, ino); + + if (!inode) + return ERR_PTR(-EACCES); + parent = d_alloc_anon(inode); + if (!parent) { + iput(inode); + parent = ERR_PTR(-ENOMEM); + } + return parent; +} + +/* + * By the time this is called, we already have created + * the directory cache entry for the new file, but it + * is so far negative - it has no inode. + * + * If the create succeeds, we fill in the inode information + * with d_instantiate(). + */ +static int ext2_create (struct inode * dir, struct dentry * dentry, int mode, struct nameidata *nd) +{ + struct inode * inode = ext2_new_inode (dir, mode); + int err = PTR_ERR(inode); + if (!IS_ERR(inode)) { + inode->i_op = &ext2_file_inode_operations; + inode->i_fop = &ext2_file_operations; + if (test_opt(inode->i_sb, NOBH)) + inode->i_mapping->a_ops = &ext2_nobh_aops; + else + inode->i_mapping->a_ops = &ext2_aops; + mark_inode_dirty(inode); + err = ext2_add_nondir(dentry, inode); + } + return err; +} + +static int ext2_mknod (struct inode * dir, struct dentry *dentry, int mode, dev_t rdev) +{ + struct inode * inode; + int err; + + if (!new_valid_dev(rdev)) + return -EINVAL; + + inode = ext2_new_inode (dir, mode); + err = PTR_ERR(inode); + if (!IS_ERR(inode)) { + init_special_inode(inode, inode->i_mode, rdev); +#ifdef CONFIG_EXT2_FS_XATTR + inode->i_op = &ext2_special_inode_operations; +#endif + mark_inode_dirty(inode); + err = ext2_add_nondir(dentry, inode); + } + return err; +} + +static int ext2_symlink (struct inode * dir, struct dentry * dentry, + const char * symname) +{ + struct super_block * sb = dir->i_sb; + int err = -ENAMETOOLONG; + unsigned l = strlen(symname)+1; + struct inode * inode; + + if (l > sb->s_blocksize) + goto out; + + inode = ext2_new_inode (dir, S_IFLNK | S_IRWXUGO); + err = PTR_ERR(inode); + if (IS_ERR(inode)) + goto out; + + if (l > sizeof (EXT2_I(inode)->i_data)) { + /* slow symlink */ + inode->i_op = &ext2_symlink_inode_operations; + if (test_opt(inode->i_sb, NOBH)) + inode->i_mapping->a_ops = &ext2_nobh_aops; + else + inode->i_mapping->a_ops = &ext2_aops; + err = page_symlink(inode, symname, l); + if (err) + goto out_fail; + } else { + /* fast symlink */ + inode->i_op = &ext2_fast_symlink_inode_operations; + memcpy((char*)(EXT2_I(inode)->i_data),symname,l); + inode->i_size = l-1; + } + mark_inode_dirty(inode); + + err = ext2_add_nondir(dentry, inode); +out: + return err; + +out_fail: + ext2_dec_count(inode); + iput (inode); + goto out; +} + +static int ext2_link (struct dentry * old_dentry, struct inode * dir, + struct dentry *dentry) +{ + struct inode *inode = old_dentry->d_inode; + + if (inode->i_nlink >= EXT2_LINK_MAX) + return -EMLINK; + + inode->i_ctime = CURRENT_TIME_SEC; + ext2_inc_count(inode); + atomic_inc(&inode->i_count); + + return ext2_add_nondir(dentry, inode); +} + +static int ext2_mkdir(struct inode * dir, struct dentry * dentry, int mode) +{ + struct inode * inode; + int err = -EMLINK; + + if (dir->i_nlink >= EXT2_LINK_MAX) + goto out; + + ext2_inc_count(dir); + + inode = ext2_new_inode (dir, S_IFDIR | mode); + err = PTR_ERR(inode); + if (IS_ERR(inode)) + goto out_dir; + + inode->i_op = &ext2_dir_inode_operations; + inode->i_fop = &ext2_dir_operations; + if (test_opt(inode->i_sb, NOBH)) + inode->i_mapping->a_ops = &ext2_nobh_aops; + else + inode->i_mapping->a_ops = &ext2_aops; + + ext2_inc_count(inode); + + err = ext2_make_empty(inode, dir); + if (err) + goto out_fail; + + err = ext2_add_link(dentry, inode); + if (err) + goto out_fail; + + d_instantiate(dentry, inode); +out: + return err; + +out_fail: + ext2_dec_count(inode); + ext2_dec_count(inode); + iput(inode); +out_dir: + ext2_dec_count(dir); + goto out; +} + +static int ext2_unlink(struct inode * dir, struct dentry *dentry) +{ + struct inode * inode = dentry->d_inode; + struct ext2_dir_entry_2 * de; + struct page * page; + int err = -ENOENT; + + de = ext2_find_entry (dir, dentry, &page); + if (!de) + goto out; + + err = ext2_delete_entry (de, page); + if (err) + goto out; + + inode->i_ctime = dir->i_ctime; + ext2_dec_count(inode); + err = 0; +out: + return err; +} + +static int ext2_rmdir (struct inode * dir, struct dentry *dentry) +{ + struct inode * inode = dentry->d_inode; + int err = -ENOTEMPTY; + + if (ext2_empty_dir(inode)) { + err = ext2_unlink(dir, dentry); + if (!err) { + inode->i_size = 0; + ext2_dec_count(inode); + ext2_dec_count(dir); + } + } + return err; +} + +static int ext2_rename (struct inode * old_dir, struct dentry * old_dentry, + struct inode * new_dir, struct dentry * new_dentry ) +{ + struct inode * old_inode = old_dentry->d_inode; + struct inode * new_inode = new_dentry->d_inode; + struct page * dir_page = NULL; + struct ext2_dir_entry_2 * dir_de = NULL; + struct page * old_page; + struct ext2_dir_entry_2 * old_de; + int err = -ENOENT; + + old_de = ext2_find_entry (old_dir, old_dentry, &old_page); + if (!old_de) + goto out; + + if (S_ISDIR(old_inode->i_mode)) { + err = -EIO; + dir_de = ext2_dotdot(old_inode, &dir_page); + if (!dir_de) + goto out_old; + } + + if (new_inode) { + struct page *new_page; + struct ext2_dir_entry_2 *new_de; + + err = -ENOTEMPTY; + if (dir_de && !ext2_empty_dir (new_inode)) + goto out_dir; + + err = -ENOENT; + new_de = ext2_find_entry (new_dir, new_dentry, &new_page); + if (!new_de) + goto out_dir; + ext2_inc_count(old_inode); + ext2_set_link(new_dir, new_de, new_page, old_inode); + new_inode->i_ctime = CURRENT_TIME_SEC; + if (dir_de) + new_inode->i_nlink--; + ext2_dec_count(new_inode); + } else { + if (dir_de) { + err = -EMLINK; + if (new_dir->i_nlink >= EXT2_LINK_MAX) + goto out_dir; + } + ext2_inc_count(old_inode); + err = ext2_add_link(new_dentry, old_inode); + if (err) { + ext2_dec_count(old_inode); + goto out_dir; + } + if (dir_de) + ext2_inc_count(new_dir); + } + + /* + * Like most other Unix systems, set the ctime for inodes on a + * rename. + * ext2_dec_count() will mark the inode dirty. + */ + old_inode->i_ctime = CURRENT_TIME_SEC; + + ext2_delete_entry (old_de, old_page); + ext2_dec_count(old_inode); + + if (dir_de) { + ext2_set_link(old_inode, dir_de, dir_page, new_dir); + ext2_dec_count(old_dir); + } + return 0; + + +out_dir: + if (dir_de) { + kunmap(dir_page); + page_cache_release(dir_page); + } +out_old: + kunmap(old_page); + page_cache_release(old_page); +out: + return err; +} + +struct inode_operations ext2_dir_inode_operations = { + .create = ext2_create, + .lookup = ext2_lookup, + .link = ext2_link, + .unlink = ext2_unlink, + .symlink = ext2_symlink, + .mkdir = ext2_mkdir, + .rmdir = ext2_rmdir, + .mknod = ext2_mknod, + .rename = ext2_rename, +#ifdef CONFIG_EXT2_FS_XATTR + .setxattr = generic_setxattr, + .getxattr = generic_getxattr, + .listxattr = ext2_listxattr, + .removexattr = generic_removexattr, +#endif + .setattr = ext2_setattr, + .permission = ext2_permission, +}; + +struct inode_operations ext2_special_inode_operations = { +#ifdef CONFIG_EXT2_FS_XATTR + .setxattr = generic_setxattr, + .getxattr = generic_getxattr, + .listxattr = ext2_listxattr, + .removexattr = generic_removexattr, +#endif + .setattr = ext2_setattr, + .permission = ext2_permission, +}; |