linux-sg2042/fs/coda/file.c

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/*
* 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/cred.h>
#include <linux/errno.h>
#include <linux/spinlock.h>
#include <linux/string.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 16:04:11 +08:00
#include <linux/slab.h>
#include <asm/uaccess.h>
#include <linux/coda.h>
#include <linux/coda_psdev.h>
#include "coda_linux.h"
#include "coda_int.h"
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_splice_read(struct file *coda_file, loff_t *ppos,
struct pipe_inode_info *pipe, size_t count,
unsigned int flags)
{
ssize_t (*splice_read)(struct file *, loff_t *,
struct pipe_inode_info *, size_t, unsigned int);
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;
splice_read = host_file->f_op->splice_read;
if (!splice_read)
splice_read = default_file_splice_read;
return splice_read(host_file, ppos, pipe, count, flags);
}
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_path.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_path.dentry->d_inode;
mutex_lock(&coda_inode->i_mutex);
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;
mutex_unlock(&coda_inode->i_mutex);
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_path.dentry->d_inode;
host_inode = host_file->f_path.dentry->d_inode;
cii = ITOC(coda_inode);
spin_lock(&cii->c_lock);
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) {
spin_unlock(&cii->c_lock);
return -EBUSY;
}
/* keep track of how often the coda_inode/host_file has been mmapped */
cii->c_mapcount++;
cfi->cfi_mapcount++;
spin_unlock(&cii->c_lock);
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;
cfi = kmalloc(sizeof(struct coda_file_info), GFP_KERNEL);
if (!cfi)
return -ENOMEM;
error = venus_open(coda_inode->i_sb, coda_i2f(coda_inode), coda_flags,
&host_file);
if (!host_file)
error = -EIO;
if (error) {
kfree(cfi);
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;
return 0;
}
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;
cfi = CODA_FTOC(coda_file);
BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC);
err = venus_close(coda_inode->i_sb, coda_i2f(coda_inode),
coda_flags, coda_file->f_cred->fsuid);
host_inode = cfi->cfi_container->f_path.dentry->d_inode;
cii = ITOC(coda_inode);
/* did we mmap this file? */
spin_lock(&cii->c_lock);
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;
}
spin_unlock(&cii->c_lock);
fput(cfi->cfi_container);
kfree(coda_file->private_data);
coda_file->private_data = NULL;
/* VFS fput ignores the return value from file_operations->release, so
* there is no use returning an error here */
return 0;
}
int coda_fsync(struct file *coda_file, loff_t start, loff_t end, int datasync)
{
struct file *host_file;
struct inode *coda_inode = coda_file->f_path.dentry->d_inode;
struct coda_file_info *cfi;
int err;
if (!(S_ISREG(coda_inode->i_mode) || S_ISDIR(coda_inode->i_mode) ||
S_ISLNK(coda_inode->i_mode)))
return -EINVAL;
err = filemap_write_and_wait_range(coda_inode->i_mapping, start, end);
if (err)
return err;
mutex_lock(&coda_inode->i_mutex);
cfi = CODA_FTOC(coda_file);
BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC);
host_file = cfi->cfi_container;
err = vfs_fsync(host_file, datasync);
if (!err && !datasync)
err = venus_fsync(coda_inode->i_sb, coda_i2f(coda_inode));
mutex_unlock(&coda_inode->i_mutex);
return err;
}
const 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,
.release = coda_release,
.fsync = coda_fsync,
.splice_read = coda_file_splice_read,
};