diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-17 02:20:36 +0400 |
---|---|---|
committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-17 02:20:36 +0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/coda/file.c | |
download | linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.xz |
Linux-2.6.12-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/coda/file.c')
-rw-r--r-- | fs/coda/file.c | 300 |
1 files changed, 300 insertions, 0 deletions
diff --git a/fs/coda/file.c b/fs/coda/file.c new file mode 100644 index 000000000000..e6bc022568f3 --- /dev/null +++ b/fs/coda/file.c @@ -0,0 +1,300 @@ +/* + * File operations for Coda. + * Original version: (C) 1996 Peter Braam + * Rewritten for Linux 2.1: (C) 1997 Carnegie Mellon University + * + * Carnegie Mellon encourages users of this code to contribute improvements + * to the Coda project. Contact Peter Braam <coda@cs.cmu.edu>. + */ + +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/time.h> +#include <linux/file.h> +#include <linux/fs.h> +#include <linux/stat.h> +#include <linux/errno.h> +#include <linux/smp_lock.h> +#include <linux/string.h> +#include <asm/uaccess.h> + +#include <linux/coda.h> +#include <linux/coda_linux.h> +#include <linux/coda_fs_i.h> +#include <linux/coda_psdev.h> +#include <linux/coda_proc.h> + +/* if CODA_STORE fails with EOPNOTSUPP, venus clearly doesn't support + * CODA_STORE/CODA_RELEASE and we fall back on using the CODA_CLOSE upcall */ +static int use_coda_close; + +static ssize_t +coda_file_read(struct file *coda_file, char __user *buf, size_t count, loff_t *ppos) +{ + struct coda_file_info *cfi; + struct file *host_file; + + cfi = CODA_FTOC(coda_file); + BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); + host_file = cfi->cfi_container; + + if (!host_file->f_op || !host_file->f_op->read) + return -EINVAL; + + return host_file->f_op->read(host_file, buf, count, ppos); +} + +static ssize_t +coda_file_sendfile(struct file *coda_file, loff_t *ppos, size_t count, + read_actor_t actor, void *target) +{ + struct coda_file_info *cfi; + struct file *host_file; + + cfi = CODA_FTOC(coda_file); + BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); + host_file = cfi->cfi_container; + + if (!host_file->f_op || !host_file->f_op->sendfile) + return -EINVAL; + + return host_file->f_op->sendfile(host_file, ppos, count, actor, target); +} + +static ssize_t +coda_file_write(struct file *coda_file, const char __user *buf, size_t count, loff_t *ppos) +{ + struct inode *host_inode, *coda_inode = coda_file->f_dentry->d_inode; + struct coda_file_info *cfi; + struct file *host_file; + ssize_t ret; + + cfi = CODA_FTOC(coda_file); + BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); + host_file = cfi->cfi_container; + + if (!host_file->f_op || !host_file->f_op->write) + return -EINVAL; + + host_inode = host_file->f_dentry->d_inode; + down(&coda_inode->i_sem); + + ret = host_file->f_op->write(host_file, buf, count, ppos); + + coda_inode->i_size = host_inode->i_size; + coda_inode->i_blocks = (coda_inode->i_size + 511) >> 9; + coda_inode->i_mtime = coda_inode->i_ctime = CURRENT_TIME_SEC; + up(&coda_inode->i_sem); + + return ret; +} + +static int +coda_file_mmap(struct file *coda_file, struct vm_area_struct *vma) +{ + struct coda_file_info *cfi; + struct coda_inode_info *cii; + struct file *host_file; + struct inode *coda_inode, *host_inode; + + cfi = CODA_FTOC(coda_file); + BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); + host_file = cfi->cfi_container; + + if (!host_file->f_op || !host_file->f_op->mmap) + return -ENODEV; + + coda_inode = coda_file->f_dentry->d_inode; + host_inode = host_file->f_dentry->d_inode; + coda_file->f_mapping = host_file->f_mapping; + if (coda_inode->i_mapping == &coda_inode->i_data) + coda_inode->i_mapping = host_inode->i_mapping; + + /* only allow additional mmaps as long as userspace isn't changing + * the container file on us! */ + else if (coda_inode->i_mapping != host_inode->i_mapping) + return -EBUSY; + + /* keep track of how often the coda_inode/host_file has been mmapped */ + cii = ITOC(coda_inode); + cii->c_mapcount++; + cfi->cfi_mapcount++; + + return host_file->f_op->mmap(host_file, vma); +} + +int coda_open(struct inode *coda_inode, struct file *coda_file) +{ + struct file *host_file = NULL; + int error; + unsigned short flags = coda_file->f_flags & (~O_EXCL); + unsigned short coda_flags = coda_flags_to_cflags(flags); + struct coda_file_info *cfi; + + coda_vfs_stat.open++; + + cfi = kmalloc(sizeof(struct coda_file_info), GFP_KERNEL); + if (!cfi) { + unlock_kernel(); + return -ENOMEM; + } + + lock_kernel(); + + error = venus_open(coda_inode->i_sb, coda_i2f(coda_inode), coda_flags, + &host_file); + if (error || !host_file) { + kfree(cfi); + unlock_kernel(); + return error; + } + + host_file->f_flags |= coda_file->f_flags & (O_APPEND | O_SYNC); + + cfi->cfi_magic = CODA_MAGIC; + cfi->cfi_mapcount = 0; + cfi->cfi_container = host_file; + + BUG_ON(coda_file->private_data != NULL); + coda_file->private_data = cfi; + + unlock_kernel(); + return 0; +} + +int coda_flush(struct file *coda_file) +{ + unsigned short flags = coda_file->f_flags & ~O_EXCL; + unsigned short coda_flags = coda_flags_to_cflags(flags); + struct coda_file_info *cfi; + struct inode *coda_inode; + int err = 0, fcnt; + + lock_kernel(); + + coda_vfs_stat.flush++; + + /* last close semantics */ + fcnt = file_count(coda_file); + if (fcnt > 1) + goto out; + + /* No need to make an upcall when we have not made any modifications + * to the file */ + if ((coda_file->f_flags & O_ACCMODE) == O_RDONLY) + goto out; + + if (use_coda_close) + goto out; + + cfi = CODA_FTOC(coda_file); + BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); + + coda_inode = coda_file->f_dentry->d_inode; + + err = venus_store(coda_inode->i_sb, coda_i2f(coda_inode), coda_flags, + coda_file->f_uid); + + if (err == -EOPNOTSUPP) { + use_coda_close = 1; + err = 0; + } + +out: + unlock_kernel(); + return err; +} + +int coda_release(struct inode *coda_inode, struct file *coda_file) +{ + unsigned short flags = (coda_file->f_flags) & (~O_EXCL); + unsigned short coda_flags = coda_flags_to_cflags(flags); + struct coda_file_info *cfi; + struct coda_inode_info *cii; + struct inode *host_inode; + int err = 0; + + lock_kernel(); + coda_vfs_stat.release++; + + if (!use_coda_close) { + err = venus_release(coda_inode->i_sb, coda_i2f(coda_inode), + coda_flags); + if (err == -EOPNOTSUPP) { + use_coda_close = 1; + err = 0; + } + } + + cfi = CODA_FTOC(coda_file); + BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); + + if (use_coda_close) + err = venus_close(coda_inode->i_sb, coda_i2f(coda_inode), + coda_flags, coda_file->f_uid); + + host_inode = cfi->cfi_container->f_dentry->d_inode; + cii = ITOC(coda_inode); + + /* did we mmap this file? */ + if (coda_inode->i_mapping == &host_inode->i_data) { + cii->c_mapcount -= cfi->cfi_mapcount; + if (!cii->c_mapcount) + coda_inode->i_mapping = &coda_inode->i_data; + } + + fput(cfi->cfi_container); + kfree(coda_file->private_data); + coda_file->private_data = NULL; + + unlock_kernel(); + return err; +} + +int coda_fsync(struct file *coda_file, struct dentry *coda_dentry, int datasync) +{ + struct file *host_file; + struct dentry *host_dentry; + struct inode *host_inode, *coda_inode = coda_dentry->d_inode; + struct coda_file_info *cfi; + int err = 0; + + if (!(S_ISREG(coda_inode->i_mode) || S_ISDIR(coda_inode->i_mode) || + S_ISLNK(coda_inode->i_mode))) + return -EINVAL; + + cfi = CODA_FTOC(coda_file); + BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); + host_file = cfi->cfi_container; + + coda_vfs_stat.fsync++; + + if (host_file->f_op && host_file->f_op->fsync) { + host_dentry = host_file->f_dentry; + host_inode = host_dentry->d_inode; + down(&host_inode->i_sem); + err = host_file->f_op->fsync(host_file, host_dentry, datasync); + up(&host_inode->i_sem); + } + + if ( !err && !datasync ) { + lock_kernel(); + err = venus_fsync(coda_inode->i_sb, coda_i2f(coda_inode)); + unlock_kernel(); + } + + return err; +} + +struct file_operations coda_file_operations = { + .llseek = generic_file_llseek, + .read = coda_file_read, + .write = coda_file_write, + .mmap = coda_file_mmap, + .open = coda_open, + .flush = coda_flush, + .release = coda_release, + .fsync = coda_fsync, + .sendfile = coda_file_sendfile, +}; + |