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-rw-r--r--fs/gfs2/ops_file.c1597
1 files changed, 1597 insertions, 0 deletions
diff --git a/fs/gfs2/ops_file.c b/fs/gfs2/ops_file.c
new file mode 100644
index 00000000000..1e6f51b74f4
--- /dev/null
+++ b/fs/gfs2/ops_file.c
@@ -0,0 +1,1597 @@
+/*
+ * 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);
+ 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);
+ 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);
+ 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);
+ 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);
+ 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_IDENTIFY: {
+ unsigned int x = GFS2_MAGIC;
+ if (copy_to_user((unsigned int __user *)arg, &x, sizeof(unsigned int)))
+ return -EFAULT;
+ return 0;
+
+ 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,
+};
+