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linux/fs/gfs2/ops_file.c

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/*
* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
* Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved.
*
* This copyrighted material is made available to anyone wishing to use,
* modify, copy, or redistribute it subject to the terms and conditions
* of the GNU General Public License v.2.
*/
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/completion.h>
#include <linux/buffer_head.h>
#include <linux/pagemap.h>
#include <linux/uio.h>
#include <linux/blkdev.h>
#include <linux/mm.h>
#include <linux/smp_lock.h>
#include <linux/gfs2_ioctl.h>
#include <asm/semaphore.h>
#include <asm/uaccess.h>
#include "gfs2.h"
#include "bmap.h"
#include "dir.h"
#include "glock.h"
#include "glops.h"
#include "inode.h"
#include "jdata.h"
#include "lm.h"
#include "log.h"
#include "meta_io.h"
#include "ops_file.h"
#include "ops_vm.h"
#include "quota.h"
#include "rgrp.h"
#include "trans.h"
/* "bad" is for NFS support */
struct filldir_bad_entry {
char *fbe_name;
unsigned int fbe_length;
uint64_t fbe_offset;
struct gfs2_inum fbe_inum;
unsigned int fbe_type;
};
struct filldir_bad {
struct gfs2_sbd *fdb_sbd;
struct filldir_bad_entry *fdb_entry;
unsigned int fdb_entry_num;
unsigned int fdb_entry_off;
char *fdb_name;
unsigned int fdb_name_size;
unsigned int fdb_name_off;
};
/* For regular, non-NFS */
struct filldir_reg {
struct gfs2_sbd *fdr_sbd;
int fdr_prefetch;
filldir_t fdr_filldir;
void *fdr_opaque;
};
typedef ssize_t(*do_rw_t) (struct file *file,
char __user *buf,
size_t size, loff_t *offset,
unsigned int num_gh, struct gfs2_holder *ghs);
/**
* gfs2_llseek - seek to a location in a file
* @file: the file
* @offset: the offset
* @origin: Where to seek from (SEEK_SET, SEEK_CUR, or SEEK_END)
*
* SEEK_END requires the glock for the file because it references the
* file's size.
*
* Returns: The new offset, or errno
*/
static loff_t gfs2_llseek(struct file *file, loff_t offset, int origin)
{
struct gfs2_inode *ip = get_v2ip(file->f_mapping->host);
struct gfs2_holder i_gh;
loff_t error;
atomic_inc(&ip->i_sbd->sd_ops_file);
if (origin == 2) {
error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
&i_gh);
if (!error) {
error = remote_llseek(file, offset, origin);
gfs2_glock_dq_uninit(&i_gh);
}
} else
error = remote_llseek(file, offset, origin);
return error;
}
static inline unsigned int vma2state(struct vm_area_struct *vma)
{
if ((vma->vm_flags & (VM_MAYWRITE | VM_MAYSHARE)) ==
(VM_MAYWRITE | VM_MAYSHARE))
return LM_ST_EXCLUSIVE;
return LM_ST_SHARED;
}
static ssize_t walk_vm_hard(struct file *file, const char __user *buf, size_t size,
loff_t *offset, do_rw_t operation)
{
struct gfs2_holder *ghs;
unsigned int num_gh = 0;
ssize_t count;
struct super_block *sb = file->f_dentry->d_inode->i_sb;
struct mm_struct *mm = current->mm;
struct vm_area_struct *vma;
unsigned long start = (unsigned long)buf;
unsigned long end = start + size;
int dumping = (current->flags & PF_DUMPCORE);
unsigned int x = 0;
for (vma = find_vma(mm, start); vma; vma = vma->vm_next) {
if (end <= vma->vm_start)
break;
if (vma->vm_file &&
vma->vm_file->f_dentry->d_inode->i_sb == sb) {
num_gh++;
}
}
ghs = kcalloc((num_gh + 1), sizeof(struct gfs2_holder), GFP_KERNEL);
if (!ghs) {
if (!dumping)
up_read(&mm->mmap_sem);
return -ENOMEM;
}
for (vma = find_vma(mm, start); vma; vma = vma->vm_next) {
if (end <= vma->vm_start)
break;
if (vma->vm_file) {
struct inode *inode = vma->vm_file->f_dentry->d_inode;
if (inode->i_sb == sb)
gfs2_holder_init(get_v2ip(inode)->i_gl,
vma2state(vma), 0, &ghs[x++]);
}
}
if (!dumping)
up_read(&mm->mmap_sem);
gfs2_assert(get_v2sdp(sb), x == num_gh);
count = operation(file, buf, size, offset, num_gh, ghs);
while (num_gh--)
gfs2_holder_uninit(&ghs[num_gh]);
kfree(ghs);
return count;
}
/**
* walk_vm - Walk the vmas associated with a buffer for read or write.
* If any of them are gfs2, pass the gfs2 inode down to the read/write
* worker function so that locks can be acquired in the correct order.
* @file: The file to read/write from/to
* @buf: The buffer to copy to/from
* @size: The amount of data requested
* @offset: The current file offset
* @operation: The read or write worker function
*
* Outputs: Offset - updated according to number of bytes written
*
* Returns: The number of bytes written, errno on failure
*/
static ssize_t walk_vm(struct file *file, const char __user *buf, size_t size,
loff_t *offset, do_rw_t operation)
{
struct gfs2_holder gh;
if (current->mm) {
struct super_block *sb = file->f_dentry->d_inode->i_sb;
struct mm_struct *mm = current->mm;
struct vm_area_struct *vma;
unsigned long start = (unsigned long)buf;
unsigned long end = start + size;
int dumping = (current->flags & PF_DUMPCORE);
if (!dumping)
down_read(&mm->mmap_sem);
for (vma = find_vma(mm, start); vma; vma = vma->vm_next) {
if (end <= vma->vm_start)
break;
if (vma->vm_file &&
vma->vm_file->f_dentry->d_inode->i_sb == sb)
goto do_locks;
}
if (!dumping)
up_read(&mm->mmap_sem);
}
return operation(file, buf, size, offset, 0, &gh);
do_locks:
return walk_vm_hard(file, buf, size, offset, operation);
}
static ssize_t do_jdata_read(struct file *file, char __user *buf, size_t size,
loff_t *offset)
{
struct gfs2_inode *ip = get_v2ip(file->f_mapping->host);
ssize_t count = 0;
if (*offset < 0)
return -EINVAL;
if (!access_ok(VERIFY_WRITE, buf, size))
return -EFAULT;
if (!(file->f_flags & O_LARGEFILE)) {
if (*offset >= MAX_NON_LFS)
return -EFBIG;
if (*offset + size > MAX_NON_LFS)
size = MAX_NON_LFS - *offset;
}
count = gfs2_jdata_read(ip, buf, *offset, size, gfs2_copy2user);
if (count > 0)
*offset += count;
return count;
}
/**
* do_read_direct - Read bytes from a file
* @file: The file to read from
* @buf: The buffer to copy into
* @size: The amount of data requested
* @offset: The current file offset
* @num_gh: The number of other locks we need to do the read
* @ghs: the locks we need plus one for our lock
*
* Outputs: Offset - updated according to number of bytes read
*
* Returns: The number of bytes read, errno on failure
*/
static ssize_t do_read_direct(struct file *file, char __user *buf, size_t size,
loff_t *offset, unsigned int num_gh,
struct gfs2_holder *ghs)
{
struct inode *inode = file->f_mapping->host;
struct gfs2_inode *ip = get_v2ip(inode);
unsigned int state = LM_ST_DEFERRED;
int flags = 0;
unsigned int x;
ssize_t count = 0;
int error;
for (x = 0; x < num_gh; x++)
if (ghs[x].gh_gl == ip->i_gl) {
state = LM_ST_SHARED;
flags |= GL_LOCAL_EXCL;
break;
}
gfs2_holder_init(ip->i_gl, state, flags, &ghs[num_gh]);
error = gfs2_glock_nq_m(num_gh + 1, ghs);
if (error)
goto out;
error = -EINVAL;
if (gfs2_is_jdata(ip))
goto out_gunlock;
if (gfs2_is_stuffed(ip)) {
size_t mask = bdev_hardsect_size(inode->i_sb->s_bdev) - 1;
if (((*offset) & mask) || (((unsigned long)buf) & mask))
goto out_gunlock;
count = do_jdata_read(file, buf, size & ~mask, offset);
} else
count = generic_file_read(file, buf, size, offset);
error = 0;
out_gunlock:
gfs2_glock_dq_m(num_gh + 1, ghs);
out:
gfs2_holder_uninit(&ghs[num_gh]);
return (count) ? count : error;
}
/**
* do_read_buf - Read bytes from a file
* @file: The file to read from
* @buf: The buffer to copy into
* @size: The amount of data requested
* @offset: The current file offset
* @num_gh: The number of other locks we need to do the read
* @ghs: the locks we need plus one for our lock
*
* Outputs: Offset - updated according to number of bytes read
*
* Returns: The number of bytes read, errno on failure
*/
static ssize_t do_read_buf(struct file *file, char __user *buf, size_t size,
loff_t *offset, unsigned int num_gh,
struct gfs2_holder *ghs)
{
struct gfs2_inode *ip = get_v2ip(file->f_mapping->host);
ssize_t count = 0;
int error;
gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &ghs[num_gh]);
error = gfs2_glock_nq_m_atime(num_gh + 1, ghs);
if (error)
goto out;
if (gfs2_is_jdata(ip))
count = do_jdata_read(file, buf, size, offset);
else
count = generic_file_read(file, buf, size, offset);
gfs2_glock_dq_m(num_gh + 1, ghs);
out:
gfs2_holder_uninit(&ghs[num_gh]);
return (count) ? count : error;
}
/**
* gfs2_read - Read bytes from a file
* @file: The file to read from
* @buf: The buffer to copy into
* @size: The amount of data requested
* @offset: The current file offset
*
* Outputs: Offset - updated according to number of bytes read
*
* Returns: The number of bytes read, errno on failure
*/
static ssize_t gfs2_read(struct file *file, char __user *buf, size_t size,
loff_t *offset)
{
atomic_inc(&get_v2sdp(file->f_mapping->host->i_sb)->sd_ops_file);
if (file->f_flags & O_DIRECT)
return walk_vm(file, buf, size, offset, do_read_direct);
else
return walk_vm(file, buf, size, offset, do_read_buf);
}
/**
* grope_mapping - feel up a mapping that needs to be written
* @buf: the start of the memory to be written
* @size: the size of the memory to be written
*
* We do this after acquiring the locks on the mapping,
* but before starting the write transaction. We need to make
* sure that we don't cause recursive transactions if blocks
* need to be allocated to the file backing the mapping.
*
* Returns: errno
*/
static int grope_mapping(const char __user *buf, size_t size)
{
const char __user *stop = buf + size;
char c;
while (buf < stop) {
if (copy_from_user(&c, buf, 1))
return -EFAULT;
buf += PAGE_CACHE_SIZE;
buf = (const char __user *)PAGE_ALIGN((unsigned long)buf);
}
return 0;
}
/**
* do_write_direct_alloc - Write bytes to a file
* @file: The file to write to
* @buf: The buffer to copy from
* @size: The amount of data requested
* @offset: The current file offset
*
* Outputs: Offset - updated according to number of bytes written
*
* Returns: The number of bytes written, errno on failure
*/
static ssize_t do_write_direct_alloc(struct file *file, const char __user *buf, size_t size,
loff_t *offset)
{
struct inode *inode = file->f_mapping->host;
struct gfs2_inode *ip = get_v2ip(inode);
struct gfs2_sbd *sdp = ip->i_sbd;
struct gfs2_alloc *al = NULL;
struct iovec local_iov = { .iov_base = buf, .iov_len = size };
struct buffer_head *dibh;
unsigned int data_blocks, ind_blocks;
ssize_t count;
int error;
gfs2_write_calc_reserv(ip, size, &data_blocks, &ind_blocks);
al = gfs2_alloc_get(ip);
error = gfs2_quota_lock(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
if (error)
goto fail;
error = gfs2_quota_check(ip, ip->i_di.di_uid, ip->i_di.di_gid);
if (error)
goto fail_gunlock_q;
al->al_requested = data_blocks + ind_blocks;
error = gfs2_inplace_reserve(ip);
if (error)
goto fail_gunlock_q;
error = gfs2_trans_begin(sdp,
al->al_rgd->rd_ri.ri_length + ind_blocks +
RES_DINODE + RES_STATFS + RES_QUOTA, 0);
if (error)
goto fail_ipres;
if ((ip->i_di.di_mode & (S_ISUID | S_ISGID)) && !capable(CAP_FSETID)) {
error = gfs2_meta_inode_buffer(ip, &dibh);
if (error)
goto fail_end_trans;
ip->i_di.di_mode &= (ip->i_di.di_mode & S_IXGRP) ?
(~(S_ISUID | S_ISGID)) : (~S_ISUID);
gfs2_trans_add_bh(ip->i_gl, dibh, 1);
gfs2_dinode_out(&ip->i_di, dibh->b_data);
brelse(dibh);
}
if (gfs2_is_stuffed(ip)) {
error = gfs2_unstuff_dinode(ip, gfs2_unstuffer_sync, NULL);
if (error)
goto fail_end_trans;
}
count = generic_file_write_nolock(file, &local_iov, 1, offset);
if (count < 0) {
error = count;
goto fail_end_trans;
}
error = gfs2_meta_inode_buffer(ip, &dibh);
if (error)
goto fail_end_trans;
if (ip->i_di.di_size < inode->i_size)
ip->i_di.di_size = inode->i_size;
ip->i_di.di_mtime = ip->i_di.di_ctime = get_seconds();
gfs2_trans_add_bh(ip->i_gl, dibh, 1);
gfs2_dinode_out(&ip->i_di, dibh->b_data);
brelse(dibh);
gfs2_trans_end(sdp);
if (file->f_flags & O_SYNC)
gfs2_log_flush_glock(ip->i_gl);
gfs2_inplace_release(ip);
gfs2_quota_unlock(ip);
gfs2_alloc_put(ip);
if (file->f_mapping->nrpages) {
error = filemap_fdatawrite(file->f_mapping);
if (!error)
error = filemap_fdatawait(file->f_mapping);
}
if (error)
return error;
return count;
fail_end_trans:
gfs2_trans_end(sdp);
fail_ipres:
gfs2_inplace_release(ip);
fail_gunlock_q:
gfs2_quota_unlock(ip);
fail:
gfs2_alloc_put(ip);
return error;
}
/**
* do_write_direct - Write bytes to a file
* @file: The file to write to
* @buf: The buffer to copy from
* @size: The amount of data requested
* @offset: The current file offset
* @num_gh: The number of other locks we need to do the read
* @gh: the locks we need plus one for our lock
*
* Outputs: Offset - updated according to number of bytes written
*
* Returns: The number of bytes written, errno on failure
*/
static ssize_t do_write_direct(struct file *file, const char __user *buf, size_t size,
loff_t *offset, unsigned int num_gh,
struct gfs2_holder *ghs)
{
struct gfs2_inode *ip = get_v2ip(file->f_mapping->host);
struct gfs2_sbd *sdp = ip->i_sbd;
struct gfs2_file *fp = get_v2fp(file);
unsigned int state = LM_ST_DEFERRED;
int alloc_required;
unsigned int x;
size_t s;
ssize_t count = 0;
int error;
if (test_bit(GFF_DID_DIRECT_ALLOC, &fp->f_flags))
state = LM_ST_EXCLUSIVE;
else
for (x = 0; x < num_gh; x++)
if (ghs[x].gh_gl == ip->i_gl) {
state = LM_ST_EXCLUSIVE;
break;
}
restart:
gfs2_holder_init(ip->i_gl, state, 0, &ghs[num_gh]);
error = gfs2_glock_nq_m(num_gh + 1, ghs);
if (error)
goto out;
error = -EINVAL;
if (gfs2_is_jdata(ip))
goto out_gunlock;
if (num_gh) {
error = grope_mapping(buf, size);
if (error)
goto out_gunlock;
}
if (file->f_flags & O_APPEND)
*offset = ip->i_di.di_size;
if (!(file->f_flags & O_LARGEFILE)) {
error = -EFBIG;
if (*offset >= MAX_NON_LFS)
goto out_gunlock;
if (*offset + size > MAX_NON_LFS)
size = MAX_NON_LFS - *offset;
}
if (gfs2_is_stuffed(ip) ||
*offset + size > ip->i_di.di_size ||
((ip->i_di.di_mode & (S_ISUID | S_ISGID)) && !capable(CAP_FSETID)))
alloc_required = 1;
else {
error = gfs2_write_alloc_required(ip, *offset, size,
&alloc_required);
if (error)
goto out_gunlock;
}
if (alloc_required && state != LM_ST_EXCLUSIVE) {
gfs2_glock_dq_m(num_gh + 1, ghs);
gfs2_holder_uninit(&ghs[num_gh]);
state = LM_ST_EXCLUSIVE;
goto restart;
}
if (alloc_required) {
set_bit(GFF_DID_DIRECT_ALLOC, &fp->f_flags);
/* split large writes into smaller atomic transactions */
while (size) {
s = gfs2_tune_get(sdp, gt_max_atomic_write);
if (s > size)
s = size;
error = do_write_direct_alloc(file, buf, s, offset);
if (error < 0)
goto out_gunlock;
buf += error;
size -= error;
count += error;
}
} else {
struct iovec local_iov = { .iov_base = buf, .iov_len = size };
struct gfs2_holder t_gh;
clear_bit(GFF_DID_DIRECT_ALLOC, &fp->f_flags);
error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED,
GL_NEVER_RECURSE, &t_gh);
if (error)
goto out_gunlock;
count = generic_file_write_nolock(file, &local_iov, 1, offset);
gfs2_glock_dq_uninit(&t_gh);
}
error = 0;
out_gunlock:
gfs2_glock_dq_m(num_gh + 1, ghs);
out:
gfs2_holder_uninit(&ghs[num_gh]);
return (count) ? count : error;
}
/**
* do_do_write_buf - Write bytes to a file
* @file: The file to write to
* @buf: The buffer to copy from
* @size: The amount of data requested
* @offset: The current file offset
*
* Outputs: Offset - updated according to number of bytes written
*
* Returns: The number of bytes written, errno on failure
*/
static ssize_t do_do_write_buf(struct file *file, const char __user *buf, size_t size,
loff_t *offset)
{
struct inode *inode = file->f_mapping->host;
struct gfs2_inode *ip = get_v2ip(inode);
struct gfs2_sbd *sdp = ip->i_sbd;
struct gfs2_alloc *al = NULL;
struct buffer_head *dibh;
unsigned int data_blocks, ind_blocks;
int alloc_required, journaled;
ssize_t count;
int error;
journaled = gfs2_is_jdata(ip);
gfs2_write_calc_reserv(ip, size, &data_blocks, &ind_blocks);
error = gfs2_write_alloc_required(ip, *offset, size, &alloc_required);
if (error)
return error;
if (alloc_required) {
al = gfs2_alloc_get(ip);
error = gfs2_quota_lock(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
if (error)
goto fail;
error = gfs2_quota_check(ip, ip->i_di.di_uid, ip->i_di.di_gid);
if (error)
goto fail_gunlock_q;
al->al_requested = data_blocks + ind_blocks;
error = gfs2_inplace_reserve(ip);
if (error)
goto fail_gunlock_q;
error = gfs2_trans_begin(sdp,
al->al_rgd->rd_ri.ri_length +
ind_blocks +
((journaled) ? data_blocks : 0) +
RES_DINODE + RES_STATFS + RES_QUOTA,
0);
if (error)
goto fail_ipres;
} else {
error = gfs2_trans_begin(sdp,
((journaled) ? data_blocks : 0) +
RES_DINODE,
0);
if (error)
goto fail_ipres;
}
if ((ip->i_di.di_mode & (S_ISUID | S_ISGID)) && !capable(CAP_FSETID)) {
error = gfs2_meta_inode_buffer(ip, &dibh);
if (error)
goto fail_end_trans;
ip->i_di.di_mode &= (ip->i_di.di_mode & S_IXGRP) ?
(~(S_ISUID | S_ISGID)) : (~S_ISUID);
gfs2_trans_add_bh(ip->i_gl, dibh, 1);
gfs2_dinode_out(&ip->i_di, dibh->b_data);
brelse(dibh);
}
if (journaled) {
count = gfs2_jdata_write(ip, buf, *offset, size,
gfs2_copy_from_user);
if (count < 0) {
error = count;
goto fail_end_trans;
}
*offset += count;
} else {
struct iovec local_iov = { .iov_base = buf, .iov_len = size };
count = generic_file_write_nolock(file, &local_iov, 1, offset);
if (count < 0) {
error = count;
goto fail_end_trans;
}
error = gfs2_meta_inode_buffer(ip, &dibh);
if (error)
goto fail_end_trans;
if (ip->i_di.di_size < inode->i_size)
ip->i_di.di_size = inode->i_size;
ip->i_di.di_mtime = ip->i_di.di_ctime = get_seconds();
gfs2_trans_add_bh(ip->i_gl, dibh, 1);
gfs2_dinode_out(&ip->i_di, dibh->b_data);
brelse(dibh);
}
gfs2_trans_end(sdp);
if (file->f_flags & O_SYNC || IS_SYNC(inode)) {
gfs2_log_flush_glock(ip->i_gl);
error = filemap_fdatawrite(file->f_mapping);
if (error == 0)
error = filemap_fdatawait(file->f_mapping);
if (error)
goto fail_ipres;
}
if (alloc_required) {
gfs2_assert_warn(sdp, count != size ||
al->al_alloced);
gfs2_inplace_release(ip);
gfs2_quota_unlock(ip);
gfs2_alloc_put(ip);
}
return count;
fail_end_trans:
gfs2_trans_end(sdp);
fail_ipres:
if (alloc_required)
gfs2_inplace_release(ip);
fail_gunlock_q:
if (alloc_required)
gfs2_quota_unlock(ip);
fail:
if (alloc_required)
gfs2_alloc_put(ip);
return error;
}
/**
* do_write_buf - Write bytes to a file
* @file: The file to write to
* @buf: The buffer to copy from
* @size: The amount of data requested
* @offset: The current file offset
* @num_gh: The number of other locks we need to do the read
* @gh: the locks we need plus one for our lock
*
* Outputs: Offset - updated according to number of bytes written
*
* Returns: The number of bytes written, errno on failure
*/
static ssize_t do_write_buf(struct file *file, const char __user *buf, size_t size,
loff_t *offset, unsigned int num_gh,
struct gfs2_holder *ghs)
{
struct gfs2_inode *ip = get_v2ip(file->f_mapping->host);
struct gfs2_sbd *sdp = ip->i_sbd;
size_t s;
ssize_t count = 0;
int error;
gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &ghs[num_gh]);
error = gfs2_glock_nq_m(num_gh + 1, ghs);
if (error)
goto out;
if (num_gh) {
error = grope_mapping(buf, size);
if (error)
goto out_gunlock;
}
if (file->f_flags & O_APPEND)
*offset = ip->i_di.di_size;
if (!(file->f_flags & O_LARGEFILE)) {
error = -EFBIG;
if (*offset >= MAX_NON_LFS)
goto out_gunlock;
if (*offset + size > MAX_NON_LFS)
size = MAX_NON_LFS - *offset;
}
/* split large writes into smaller atomic transactions */
while (size) {
s = gfs2_tune_get(sdp, gt_max_atomic_write);
if (s > size)
s = size;
error = do_do_write_buf(file, buf, s, offset);
if (error < 0)
goto out_gunlock;
buf += error;
size -= error;
count += error;
}
error = 0;
out_gunlock:
gfs2_glock_dq_m(num_gh + 1, ghs);
out:
gfs2_holder_uninit(&ghs[num_gh]);
return (count) ? count : error;
}
/**
* gfs2_write - Write bytes to a file
* @file: The file to write to
* @buf: The buffer to copy from
* @size: The amount of data requested
* @offset: The current file offset
*
* Outputs: Offset - updated according to number of bytes written
*
* Returns: The number of bytes written, errno on failure
*/
static ssize_t gfs2_write(struct file *file, const char __user *buf,
size_t size, loff_t *offset)
{
struct inode *inode = file->f_mapping->host;
ssize_t count;
atomic_inc(&get_v2sdp(inode->i_sb)->sd_ops_file);
if (*offset < 0)
return -EINVAL;
if (!access_ok(VERIFY_READ, buf, size))
return -EFAULT;
mutex_lock(&inode->i_mutex);
if (file->f_flags & O_DIRECT)
count = walk_vm(file, buf, size, offset,
do_write_direct);
else
count = walk_vm(file, buf, size, offset, do_write_buf);
mutex_unlock(&inode->i_mutex);
return count;
}
/**
* filldir_reg_func - Report a directory entry to the caller of gfs2_dir_read()
* @opaque: opaque data used by the function
* @name: the name of the directory entry
* @length: the length of the name
* @offset: the entry's offset in the directory
* @inum: the inode number the entry points to
* @type: the type of inode the entry points to
*
* Returns: 0 on success, 1 if buffer full
*/
static int filldir_reg_func(void *opaque, const char *name, unsigned int length,
uint64_t offset, struct gfs2_inum *inum,
unsigned int type)
{
struct filldir_reg *fdr = (struct filldir_reg *)opaque;
struct gfs2_sbd *sdp = fdr->fdr_sbd;
int error;
error = fdr->fdr_filldir(fdr->fdr_opaque, name, length, offset,
inum->no_formal_ino, type);
if (error)
return 1;
if (fdr->fdr_prefetch && !(length == 1 && *name == '.')) {
gfs2_glock_prefetch_num(sdp,
inum->no_addr, &gfs2_inode_glops,
LM_ST_SHARED, LM_FLAG_TRY | LM_FLAG_ANY);
gfs2_glock_prefetch_num(sdp,
inum->no_addr, &gfs2_iopen_glops,
LM_ST_SHARED, LM_FLAG_TRY);
}
return 0;
}
/**
* readdir_reg - Read directory entries from a directory
* @file: The directory to read from
* @dirent: Buffer for dirents
* @filldir: Function used to do the copying
*
* Returns: errno
*/
static int readdir_reg(struct file *file, void *dirent, filldir_t filldir)
{
struct gfs2_inode *dip = get_v2ip(file->f_mapping->host);
struct filldir_reg fdr;
struct gfs2_holder d_gh;
uint64_t offset = file->f_pos;
int error;
fdr.fdr_sbd = dip->i_sbd;
fdr.fdr_prefetch = 1;
fdr.fdr_filldir = filldir;
fdr.fdr_opaque = dirent;
gfs2_holder_init(dip->i_gl, LM_ST_SHARED, GL_ATIME, &d_gh);
error = gfs2_glock_nq_atime(&d_gh);
if (error) {
gfs2_holder_uninit(&d_gh);
return error;
}
error = gfs2_dir_read(dip, &offset, &fdr, filldir_reg_func);
gfs2_glock_dq_uninit(&d_gh);
file->f_pos = offset;
return error;
}
/**
* filldir_bad_func - Report a directory entry to the caller of gfs2_dir_read()
* @opaque: opaque data used by the function
* @name: the name of the directory entry
* @length: the length of the name
* @offset: the entry's offset in the directory
* @inum: the inode number the entry points to
* @type: the type of inode the entry points to
*
* For supporting NFS.
*
* Returns: 0 on success, 1 if buffer full
*/
static int filldir_bad_func(void *opaque, const char *name, unsigned int length,
uint64_t offset, struct gfs2_inum *inum,
unsigned int type)
{
struct filldir_bad *fdb = (struct filldir_bad *)opaque;
struct gfs2_sbd *sdp = fdb->fdb_sbd;
struct filldir_bad_entry *fbe;
if (fdb->fdb_entry_off == fdb->fdb_entry_num ||
fdb->fdb_name_off + length > fdb->fdb_name_size)
return 1;
fbe = &fdb->fdb_entry[fdb->fdb_entry_off];
fbe->fbe_name = fdb->fdb_name + fdb->fdb_name_off;
memcpy(fbe->fbe_name, name, length);
fbe->fbe_length = length;
fbe->fbe_offset = offset;
fbe->fbe_inum = *inum;
fbe->fbe_type = type;
fdb->fdb_entry_off++;
fdb->fdb_name_off += length;
if (!(length == 1 && *name == '.')) {
gfs2_glock_prefetch_num(sdp,
inum->no_addr, &gfs2_inode_glops,
LM_ST_SHARED, LM_FLAG_TRY | LM_FLAG_ANY);
gfs2_glock_prefetch_num(sdp,
inum->no_addr, &gfs2_iopen_glops,
LM_ST_SHARED, LM_FLAG_TRY);
}
return 0;
}
/**
* readdir_bad - Read directory entries from a directory
* @file: The directory to read from
* @dirent: Buffer for dirents
* @filldir: Function used to do the copying
*
* For supporting NFS.
*
* Returns: errno
*/
static int readdir_bad(struct file *file, void *dirent, filldir_t filldir)
{
struct gfs2_inode *dip = get_v2ip(file->f_mapping->host);
struct gfs2_sbd *sdp = dip->i_sbd;
struct filldir_reg fdr;
unsigned int entries, size;
struct filldir_bad *fdb;
struct gfs2_holder d_gh;
uint64_t offset = file->f_pos;
unsigned int x;
struct filldir_bad_entry *fbe;
int error;
entries = gfs2_tune_get(sdp, gt_entries_per_readdir);
size = sizeof(struct filldir_bad) +
entries * (sizeof(struct filldir_bad_entry) + GFS2_FAST_NAME_SIZE);
fdb = kzalloc(size, GFP_KERNEL);
if (!fdb)
return -ENOMEM;
fdb->fdb_sbd = sdp;
fdb->fdb_entry = (struct filldir_bad_entry *)(fdb + 1);
fdb->fdb_entry_num = entries;
fdb->fdb_name = ((char *)fdb) + sizeof(struct filldir_bad) +
entries * sizeof(struct filldir_bad_entry);
fdb->fdb_name_size = entries * GFS2_FAST_NAME_SIZE;
gfs2_holder_init(dip->i_gl, LM_ST_SHARED, GL_ATIME, &d_gh);
error = gfs2_glock_nq_atime(&d_gh);
if (error) {
gfs2_holder_uninit(&d_gh);
goto out;
}
error = gfs2_dir_read(dip, &offset, fdb, filldir_bad_func);
gfs2_glock_dq_uninit(&d_gh);
fdr.fdr_sbd = sdp;
fdr.fdr_prefetch = 0;
fdr.fdr_filldir = filldir;
fdr.fdr_opaque = dirent;
for (x = 0; x < fdb->fdb_entry_off; x++) {
fbe = &fdb->fdb_entry[x];
error = filldir_reg_func(&fdr,
fbe->fbe_name, fbe->fbe_length,
fbe->fbe_offset,
&fbe->fbe_inum, fbe->fbe_type);
if (error) {
file->f_pos = fbe->fbe_offset;
error = 0;
goto out;
}
}
file->f_pos = offset;
out:
kfree(fdb);
return error;
}
/**
* gfs2_readdir - Read directory entries from a directory
* @file: The directory to read from
* @dirent: Buffer for dirents
* @filldir: Function used to do the copying
*
* Returns: errno
*/
static int gfs2_readdir(struct file *file, void *dirent, filldir_t filldir)
{
int error;
atomic_inc(&get_v2sdp(file->f_mapping->host->i_sb)->sd_ops_file);
if (strcmp(current->comm, "nfsd") != 0)
error = readdir_reg(file, dirent, filldir);
else
error = readdir_bad(file, dirent, filldir);
return error;
}
static int gfs2_ioctl_flags(struct gfs2_inode *ip, unsigned int cmd, unsigned long arg)
{
unsigned int lmode = (cmd == GFS2_IOCTL_SETFLAGS) ? LM_ST_EXCLUSIVE : LM_ST_SHARED;
struct buffer_head *dibh;
struct gfs2_holder i_gh;
int error;
__u32 flags = 0, change;
if (cmd == GFS2_IOCTL_SETFLAGS) {
error = get_user(flags, (__u32 __user *)arg);
if (error)
return -EFAULT;
}
error = gfs2_glock_nq_init(ip->i_gl, lmode, 0, &i_gh);
if (error)
return error;
if (cmd == GFS2_IOCTL_SETFLAGS) {
change = flags ^ ip->i_di.di_flags;
error = -EPERM;
if (change & (GFS2_DIF_IMMUTABLE|GFS2_DIF_APPENDONLY)) {
if (!capable(CAP_LINUX_IMMUTABLE))
goto out;
}
error = -EINVAL;
if (flags & (GFS2_DIF_JDATA|GFS2_DIF_DIRECTIO)) {
if (!S_ISREG(ip->i_di.di_mode))
goto out;
/* FIXME: Would be nice not to require the following test */
if ((flags & GFS2_DIF_JDATA) && ip->i_di.di_size)
goto out;
}
if (flags & (GFS2_DIF_INHERIT_JDATA|GFS2_DIF_INHERIT_DIRECTIO)) {
if (!S_ISDIR(ip->i_di.di_mode))
goto out;
}
error = gfs2_trans_begin(ip->i_sbd, RES_DINODE, 0);
if (error)
goto out;
error = gfs2_meta_inode_buffer(ip, &dibh);
if (error)
goto out_trans_end;
ip->i_di.di_flags = flags;
gfs2_trans_add_bh(ip->i_gl, dibh, 1);
gfs2_dinode_out(&ip->i_di, dibh->b_data);
brelse(dibh);
out_trans_end:
gfs2_trans_end(ip->i_sbd);
} else {
flags = ip->i_di.di_flags;
}
out:
gfs2_glock_dq_uninit(&i_gh);
if (cmd == GFS2_IOCTL_GETFLAGS) {
if (put_user(flags, (__u32 __user *)arg))
return -EFAULT;
}
return error;
}
/**
* gfs2_ioctl - do an ioctl on a file
* @inode: the inode
* @file: the file pointer
* @cmd: the ioctl command
* @arg: the argument
*
* Returns: errno
*/
static int gfs2_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
unsigned long arg)
{
struct gfs2_inode *ip = get_v2ip(inode);
atomic_inc(&ip->i_sbd->sd_ops_file);
switch (cmd) {
case GFS2_IOCTL_SETFLAGS:
case GFS2_IOCTL_GETFLAGS:
return gfs2_ioctl_flags(ip, cmd, arg);
default:
return -ENOTTY;
}
}
/**
* gfs2_mmap -
* @file: The file to map
* @vma: The VMA which described the mapping
*
* Returns: 0 or error code
*/
static int gfs2_mmap(struct file *file, struct vm_area_struct *vma)
{
struct gfs2_inode *ip = get_v2ip(file->f_mapping->host);
struct gfs2_holder i_gh;
int error;
atomic_inc(&ip->i_sbd->sd_ops_file);
gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &i_gh);
error = gfs2_glock_nq_atime(&i_gh);
if (error) {
gfs2_holder_uninit(&i_gh);
return error;
}
if (gfs2_is_jdata(ip)) {
if (vma->vm_flags & VM_MAYSHARE)
error = -EOPNOTSUPP;
else
vma->vm_ops = &gfs2_vm_ops_private;
} else {
/* This is VM_MAYWRITE instead of VM_WRITE because a call
to mprotect() can turn on VM_WRITE later. */
if ((vma->vm_flags & (VM_MAYSHARE | VM_MAYWRITE)) ==
(VM_MAYSHARE | VM_MAYWRITE))
vma->vm_ops = &gfs2_vm_ops_sharewrite;
else
vma->vm_ops = &gfs2_vm_ops_private;
}
gfs2_glock_dq_uninit(&i_gh);
return error;
}
/**
* gfs2_open - open a file
* @inode: the inode to open
* @file: the struct file for this opening
*
* Returns: errno
*/
static int gfs2_open(struct inode *inode, struct file *file)
{
struct gfs2_inode *ip = get_v2ip(inode);
struct gfs2_holder i_gh;
struct gfs2_file *fp;
int error;
atomic_inc(&ip->i_sbd->sd_ops_file);
fp = kzalloc(sizeof(struct gfs2_file), GFP_KERNEL);
if (!fp)
return -ENOMEM;
init_MUTEX(&fp->f_fl_mutex);
fp->f_inode = ip;
fp->f_vfile = file;
gfs2_assert_warn(ip->i_sbd, !get_v2fp(file));
set_v2fp(file, fp);
if (S_ISREG(ip->i_di.di_mode)) {
error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
&i_gh);
if (error)
goto fail;
if (!(file->f_flags & O_LARGEFILE) &&
ip->i_di.di_size > MAX_NON_LFS) {
error = -EFBIG;
goto fail_gunlock;
}
/* Listen to the Direct I/O flag */
if (ip->i_di.di_flags & GFS2_DIF_DIRECTIO)
file->f_flags |= O_DIRECT;
/* Don't let the user open O_DIRECT on a jdata file */
if ((file->f_flags & O_DIRECT) && gfs2_is_jdata(ip)) {
error = -EINVAL;
goto fail_gunlock;
}
gfs2_glock_dq_uninit(&i_gh);
}
return 0;
fail_gunlock:
gfs2_glock_dq_uninit(&i_gh);
fail:
set_v2fp(file, NULL);
kfree(fp);
return error;
}
/**
* gfs2_close - called to close a struct file
* @inode: the inode the struct file belongs to
* @file: the struct file being closed
*
* Returns: errno
*/
static int gfs2_close(struct inode *inode, struct file *file)
{
struct gfs2_sbd *sdp = get_v2sdp(inode->i_sb);
struct gfs2_file *fp;
atomic_inc(&sdp->sd_ops_file);
fp = get_v2fp(file);
set_v2fp(file, NULL);
if (gfs2_assert_warn(sdp, fp))
return -EIO;
kfree(fp);
return 0;
}
/**
* gfs2_fsync - sync the dirty data for a file (across the cluster)
* @file: the file that points to the dentry (we ignore this)
* @dentry: the dentry that points to the inode to sync
*
* Returns: errno
*/
static int gfs2_fsync(struct file *file, struct dentry *dentry, int datasync)
{
struct gfs2_inode *ip = get_v2ip(dentry->d_inode);
atomic_inc(&ip->i_sbd->sd_ops_file);
gfs2_log_flush_glock(ip->i_gl);
return 0;
}
/**
* gfs2_lock - acquire/release a posix lock on a file
* @file: the file pointer
* @cmd: either modify or retrieve lock state, possibly wait
* @fl: type and range of lock
*
* Returns: errno
*/
static int gfs2_lock(struct file *file, int cmd, struct file_lock *fl)
{
struct gfs2_inode *ip = get_v2ip(file->f_mapping->host);
struct gfs2_sbd *sdp = ip->i_sbd;
struct lm_lockname name =
{ .ln_number = ip->i_num.no_addr,
.ln_type = LM_TYPE_PLOCK };
atomic_inc(&sdp->sd_ops_file);
if (!(fl->fl_flags & FL_POSIX))
return -ENOLCK;
if ((ip->i_di.di_mode & (S_ISGID | S_IXGRP)) == S_ISGID)
return -ENOLCK;
if (sdp->sd_args.ar_localflocks) {
if (IS_GETLK(cmd)) {
struct file_lock *tmp;
lock_kernel();
tmp = posix_test_lock(file, fl);
fl->fl_type = F_UNLCK;
if (tmp)
memcpy(fl, tmp, sizeof(struct file_lock));
unlock_kernel();
return 0;
} else {
int error;
lock_kernel();
error = posix_lock_file_wait(file, fl);
unlock_kernel();
return error;
}
}
if (IS_GETLK(cmd))
return gfs2_lm_plock_get(sdp, &name, file, fl);
else if (fl->fl_type == F_UNLCK)
return gfs2_lm_punlock(sdp, &name, file, fl);
else
return gfs2_lm_plock(sdp, &name, file, cmd, fl);
}
/**
* gfs2_sendfile - Send bytes to a file or socket
* @in_file: The file to read from
* @out_file: The file to write to
* @count: The amount of data
* @offset: The beginning file offset
*
* Outputs: offset - updated according to number of bytes read
*
* Returns: The number of bytes sent, errno on failure
*/
static ssize_t gfs2_sendfile(struct file *in_file, loff_t *offset, size_t count,
read_actor_t actor, void *target)
{
struct gfs2_inode *ip = get_v2ip(in_file->f_mapping->host);
struct gfs2_holder gh;
ssize_t retval;
atomic_inc(&ip->i_sbd->sd_ops_file);
gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &gh);
retval = gfs2_glock_nq_atime(&gh);
if (retval)
goto out;
if (gfs2_is_jdata(ip))
retval = -EOPNOTSUPP;
else
retval = generic_file_sendfile(in_file, offset, count, actor,
target);
gfs2_glock_dq(&gh);
out:
gfs2_holder_uninit(&gh);
return retval;
}
static int do_flock(struct file *file, int cmd, struct file_lock *fl)
{
struct gfs2_file *fp = get_v2fp(file);
struct gfs2_holder *fl_gh = &fp->f_fl_gh;
struct gfs2_inode *ip = fp->f_inode;
struct gfs2_glock *gl;
unsigned int state;
int flags;
int error = 0;
state = (fl->fl_type == F_WRLCK) ? LM_ST_EXCLUSIVE : LM_ST_SHARED;
flags = ((IS_SETLKW(cmd)) ? 0 : LM_FLAG_TRY) | GL_EXACT | GL_NOCACHE;
down(&fp->f_fl_mutex);
gl = fl_gh->gh_gl;
if (gl) {
if (fl_gh->gh_state == state)
goto out;
gfs2_glock_hold(gl);
flock_lock_file_wait(file,
&(struct file_lock){.fl_type = F_UNLCK});
gfs2_glock_dq_uninit(fl_gh);
} else {
error = gfs2_glock_get(ip->i_sbd,
ip->i_num.no_addr, &gfs2_flock_glops,
CREATE, &gl);
if (error)
goto out;
}
gfs2_holder_init(gl, state, flags, fl_gh);
gfs2_glock_put(gl);
error = gfs2_glock_nq(fl_gh);
if (error) {
gfs2_holder_uninit(fl_gh);
if (error == GLR_TRYFAILED)
error = -EAGAIN;
} else {
error = flock_lock_file_wait(file, fl);
gfs2_assert_warn(ip->i_sbd, !error);
}
out:
up(&fp->f_fl_mutex);
return error;
}
static void do_unflock(struct file *file, struct file_lock *fl)
{
struct gfs2_file *fp = get_v2fp(file);
struct gfs2_holder *fl_gh = &fp->f_fl_gh;
down(&fp->f_fl_mutex);
flock_lock_file_wait(file, fl);
if (fl_gh->gh_gl)
gfs2_glock_dq_uninit(fl_gh);
up(&fp->f_fl_mutex);
}
/**
* gfs2_flock - acquire/release a flock lock on a file
* @file: the file pointer
* @cmd: either modify or retrieve lock state, possibly wait
* @fl: type and range of lock
*
* Returns: errno
*/
static int gfs2_flock(struct file *file, int cmd, struct file_lock *fl)
{
struct gfs2_inode *ip = get_v2ip(file->f_mapping->host);
struct gfs2_sbd *sdp = ip->i_sbd;
atomic_inc(&ip->i_sbd->sd_ops_file);
if (!(fl->fl_flags & FL_FLOCK))
return -ENOLCK;
if ((ip->i_di.di_mode & (S_ISGID | S_IXGRP)) == S_ISGID)
return -ENOLCK;
if (sdp->sd_args.ar_localflocks)
return flock_lock_file_wait(file, fl);
if (fl->fl_type == F_UNLCK) {
do_unflock(file, fl);
return 0;
} else
return do_flock(file, cmd, fl);
}
struct file_operations gfs2_file_fops = {
.llseek = gfs2_llseek,
.read = gfs2_read,
.write = gfs2_write,
.ioctl = gfs2_ioctl,
.mmap = gfs2_mmap,
.open = gfs2_open,
.release = gfs2_close,
.fsync = gfs2_fsync,
.lock = gfs2_lock,
.sendfile = gfs2_sendfile,
.flock = gfs2_flock,
};
struct file_operations gfs2_dir_fops = {
.readdir = gfs2_readdir,
.ioctl = gfs2_ioctl,
.open = gfs2_open,
.release = gfs2_close,
.fsync = gfs2_fsync,
.lock = gfs2_lock,
.flock = gfs2_flock,
};
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