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/* 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/coda_psdev.h>
#include <linux/pagemap.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 = {
.readlink = generic_readlink,
.get_link = page_get_link,
.put_link = page_put_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);
inode = iget5_locked(sb, hash, coda_test_inode, coda_set_inode, fid);
if (!inode)
return ERR_PTR(-ENOMEM);
if (inode->i_state & 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;
unlock_new_inode(inode);
}
/* always replace the attributes, type might have changed */
coda_fill_inode(inode, attr);
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);
if ( !sb ) {
pr_warn("%s: no sb!\n", __func__);
return NULL;
}
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->i_state & I_NEW);
return inode;
}
/* 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);
}
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