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// SPDX-License-Identifier: GPL-2.0/* cnode related routines for the coda kernel code   (C) 1996 Peter Braam   */ #include <linux/types.h>#include <linux/string.h>#include <linux/time.h> #include <linux/coda.h>#include <linux/pagemap.h>#include "coda_psdev.h"#include "coda_linux.h" static inline int coda_fideq(struct CodaFid *fid1, struct CodaFid *fid2){	return memcmp(fid1, fid2, sizeof(*fid1)) == 0;} static const struct inode_operations coda_symlink_inode_operations = {	.get_link	= page_get_link,	.setattr	= coda_setattr,}; /* cnode.c */static void coda_fill_inode(struct inode *inode, struct coda_vattr *attr){        coda_vattr_to_iattr(inode, attr);         if (S_ISREG(inode->i_mode)) {                inode->i_op = &coda_file_inode_operations;                inode->i_fop = &coda_file_operations;        } else if (S_ISDIR(inode->i_mode)) {                inode->i_op = &coda_dir_inode_operations;                inode->i_fop = &coda_dir_operations;        } else if (S_ISLNK(inode->i_mode)) {		inode->i_op = &coda_symlink_inode_operations;		inode_nohighmem(inode);		inode->i_data.a_ops = &coda_symlink_aops;		inode->i_mapping = &inode->i_data;	} else                init_special_inode(inode, inode->i_mode, huge_decode_dev(attr->va_rdev));} static int coda_test_inode(struct inode *inode, void *data){	struct CodaFid *fid = (struct CodaFid *)data;	struct coda_inode_info *cii = ITOC(inode);	return coda_fideq(&cii->c_fid, fid);} static int coda_set_inode(struct inode *inode, void *data){	struct CodaFid *fid = (struct CodaFid *)data;	struct coda_inode_info *cii = ITOC(inode);	cii->c_fid = *fid;	return 0;} struct inode * coda_iget(struct super_block * sb, struct CodaFid * fid,			 struct coda_vattr * attr){	struct inode *inode;	struct coda_inode_info *cii;	unsigned long hash = coda_f2i(fid);	umode_t inode_type = coda_inode_type(attr); retry:	inode = iget5_locked(sb, hash, coda_test_inode, coda_set_inode, fid);	if (!inode)		return ERR_PTR(-ENOMEM); 	if (inode_state_read_once(inode) & I_NEW) {		cii = ITOC(inode);		/* we still need to set i_ino for things like stat(2) */		inode->i_ino = hash;		/* inode is locked and unique, no need to grab cii->c_lock */		cii->c_mapcount = 0;		coda_fill_inode(inode, attr);		unlock_new_inode(inode);	} else if ((inode->i_mode & S_IFMT) != inode_type) {		/* Inode has changed type, mark bad and grab a new one */		remove_inode_hash(inode);		coda_flag_inode(inode, C_PURGE);		iput(inode);		goto retry;	}	return inode;} /* this is effectively coda_iget:   - get attributes (might be cached)   - get the inode for the fid using vfs iget   - link the two up if this is needed   - fill in the attributes*/struct inode *coda_cnode_make(struct CodaFid *fid, struct super_block *sb){        struct coda_vattr attr;	struct inode *inode;        int error;        	/* We get inode numbers from Venus -- see venus source */	error = venus_getattr(sb, fid, &attr);	if (error)		return ERR_PTR(error); 	inode = coda_iget(sb, fid, &attr);	if (IS_ERR(inode))		pr_warn("%s: coda_iget failed\n", __func__);	return inode;}  /* Although we treat Coda file identifiers as immutable, there is one * special case for files created during a disconnection where they may * not be globally unique. When an identifier collision is detected we * first try to flush the cached inode from the kernel and finally * resort to renaming/rehashing in-place. Userspace remembers both old * and new values of the identifier to handle any in-flight upcalls. * The real solution is to use globally unique UUIDs as identifiers, but * retrofitting the existing userspace code for this is non-trivial. */void coda_replace_fid(struct inode *inode, struct CodaFid *oldfid, 		      struct CodaFid *newfid){	struct coda_inode_info *cii = ITOC(inode);	unsigned long hash = coda_f2i(newfid);		BUG_ON(!coda_fideq(&cii->c_fid, oldfid)); 	/* replace fid and rehash inode */	/* XXX we probably need to hold some lock here! */	remove_inode_hash(inode);	cii->c_fid = *newfid;	inode->i_ino = hash;	__insert_inode_hash(inode, hash);} /* convert a fid to an inode. */struct inode *coda_fid_to_inode(struct CodaFid *fid, struct super_block *sb) {	struct inode *inode;	unsigned long hash = coda_f2i(fid); 	inode = ilookup5(sb, hash, coda_test_inode, fid);	if ( !inode )		return NULL; 	/* we should never see newly created inodes because we intentionally	 * fail in the initialization callback */	BUG_ON(inode_state_read_once(inode) & I_NEW); 	return inode;} struct coda_file_info *coda_ftoc(struct file *file){	struct coda_file_info *cfi = file->private_data; 	BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); 	return cfi; } /* the CONTROL inode is made without asking attributes from Venus */struct inode *coda_cnode_makectl(struct super_block *sb){	struct inode *inode = new_inode(sb);	if (inode) {		inode->i_ino = CTL_INO;		inode->i_op = &coda_ioctl_inode_operations;		inode->i_fop = &coda_ioctl_operations;		inode->i_mode = 0444;		return inode;	}	return ERR_PTR(-ENOMEM);}