diff options
Diffstat (limited to 'fs/coda/cnode.c')
| -rw-r--r-- | fs/coda/cnode.c | 196 |
1 files changed, 196 insertions, 0 deletions
diff --git a/fs/coda/cnode.c b/fs/coda/cnode.c new file mode 100644 index 000000000..abf8a855f --- /dev/null +++ b/fs/coda/cnode.c @@ -0,0 +1,196 @@ +/* cnode related routines for the coda kernel code + Peter Braam, Sep 1996. + */ + +#include <linux/types.h> +#include <linux/time.h> + +#include <linux/coda.h> +#include <linux/coda_linux.h> +#include <linux/coda_psdev.h> +#include <linux/coda_cnode.h> + +extern int coda_debug; +extern int coda_print_entry; +extern int coda_fetch_inode(struct inode *inode, struct coda_vattr *attr); + +/* cnode.c */ +struct cnode *coda_cnode_alloc(void); +void coda_cnode_free(struct cnode *); +int coda_cnode_make(struct inode **inode, ViceFid *fid, struct super_block *sb); + +/* return pointer to new empty cnode */ +struct cnode *coda_cnode_alloc(void) +{ + struct cnode *result = NULL; + + CODA_ALLOC(result, struct cnode *, sizeof(struct cnode)); + if ( !result ) { + printk("coda_cnode_alloc: kmalloc returned NULL.\n"); + return result; + } + + memset(result, 0, (int) sizeof(struct cnode)); + return result; +} + +/* release cnode memory */ +void coda_cnode_free(struct cnode *cinode) +{ + CODA_FREE(cinode, sizeof(struct cnode)); +} + +/* 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 +*/ +int coda_cnode_make(struct inode **inode, ViceFid *fid, struct super_block *sb) +{ + struct cnode *cnp; + struct coda_vattr attr; + int error; + ino_t ino; + char str[50]; + + ENTRY; + + /* + * We get inode numbers from Venus -- see venus source + */ + + error = venus_getattr(sb, fid, &attr); + if ( error ) { + printk("coda_cnode_make: coda_getvattr returned %d for %s.\n", + error, coda_f2s(fid, str)); + *inode = NULL; + return error; + } + + ino = attr.va_fileid; + *inode = iget(sb, ino); + if ( !*inode ) { + printk("coda_cnode_make: iget failed\n"); + return -ENOMEM; + } + + /* link the cnode and the vfs inode + if this inode is not linked yet + */ + if ( !(*inode)->u.generic_ip ) { + cnp = coda_cnode_alloc(); + if ( !cnp ) { + printk("coda_cnode_make: coda_cnode_alloc failed.\n"); + clear_inode(*inode); + return -ENOMEM; + } + cnp->c_fid = *fid; + cnp->c_magic = CODA_CNODE_MAGIC; + cnp->c_flags = C_VATTR; + cnp->c_vnode = *inode; + (*inode)->u.generic_ip = (void *) cnp; + CDEBUG(D_CNODE, "LINKING: ino %ld, count %d at 0x%x with cnp 0x%x, cnp->c_vnode 0x%x, in->u.generic_ip 0x%x\n", (*inode)->i_ino, (*inode)->i_count, (int) (*inode), (int) cnp, (int)cnp->c_vnode, (int) (*inode)->u.generic_ip); + } else { + cnp = (struct cnode *)(*inode)->u.generic_ip; + CDEBUG(D_CNODE, "FOUND linked: ino %ld, count %d, at 0x%x with cnp 0x%x, cnp->c_vnode 0x%x\n", (*inode)->i_ino, (*inode)->i_count, (int) (*inode), (int) cnp, (int)cnp->c_vnode); + } + CHECK_CNODE(cnp); + + /* refresh the attributes */ + error = coda_fetch_inode(*inode, &attr); + if ( error ) { + printk("coda_cnode_make: fetch_inode returned %d\n", error); + clear_inode(*inode); + coda_cnode_free(cnp); + return -error; + } + CDEBUG(D_CNODE, "Done linking: ino %ld, at 0x%x with cnp 0x%x, cnp->c_vnode 0x%x\n", (*inode)->i_ino, (int) (*inode), (int) cnp, (int)cnp->c_vnode); + + EXIT; + return 0; +} + + +inline int coda_fideq(ViceFid *fid1, ViceFid *fid2) +{ + int eq; + eq = ( (fid1->Vnode == fid2->Vnode) && + (fid1->Volume == fid2->Volume) && + (fid1->Unique == fid2->Unique) ); + return eq; +} + + +/* compute the inode number from the FID + same routine as in vproc.cc (venus) + XXX look at the exceptional case of root fids etc +*/ +static ino_t +coda_fid2ino(ViceFid *fid) +{ + u_long ROOT_VNODE = 1; + u_long ROOT_UNIQUE = 1; + ViceFid nullfid = { 0, 0, 0}; + + if ( coda_fideq(fid, &nullfid) ) { + printk("coda_fid2ino: called with NULL Fid!\n"); + return 0; + } + + /* what do we return for the root fid */ + + /* Other volume root. We need the relevant mount point's + fid, but we don't know what that is! */ + if (fid->Vnode == ROOT_VNODE && fid->Unique == ROOT_UNIQUE) { + return(0); + } + + /* Non volume root. */ + return(fid->Unique + (fid->Vnode << 10) + (fid->Volume << 20)); +} + +/* convert a fid to an inode. Avoids having a hash table + such as present in the Mach minicache */ +struct inode * +coda_fid2inode(ViceFid *fid, struct super_block *sb) { + ino_t nr; + struct inode *inode; + struct cnode *cnp; + + nr = coda_fid2ino(fid); + inode = iget(sb, nr); + + /* check if this inode is linked to a cnode */ + cnp = (struct cnode *) inode->u.generic_ip; + if ( cnp == NULL ) { + iput(inode); + return NULL; + } + /* make sure fid is the one we want */ + if ( !coda_fideq(fid, &(cnp->c_fid)) ) { + printk("coda_fid2inode: bad cnode! Tell Peter.\n"); + iput(inode); + return NULL; + } + + iput(inode); + return inode; +} + +/* the CONTROL inode is made without asking attributes from Venus */ +int coda_cnode_makectl(struct inode **inode, struct super_block *sb) +{ + int error = 0; + + *inode = iget(sb, CTL_INO); + if ( *inode ) { + (*inode)->i_op = &coda_ioctl_inode_operations; + (*inode)->i_mode = 00444; + error = 0; + } else { + error = -ENOMEM; + } + + return error; +} |