summaryrefslogtreecommitdiffstats
path: root/fs/gfs2/ops_file.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/gfs2/ops_file.c')
-rw-r--r--fs/gfs2/ops_file.c661
1 files changed, 661 insertions, 0 deletions
diff --git a/fs/gfs2/ops_file.c b/fs/gfs2/ops_file.c
new file mode 100644
index 000000000000..3064f133bf3c
--- /dev/null
+++ b/fs/gfs2/ops_file.c
@@ -0,0 +1,661 @@
+/*
+ * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
+ * Copyright (C) 2004-2006 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 version 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/fs.h>
+#include <linux/gfs2_ondisk.h>
+#include <linux/ext2_fs.h>
+#include <linux/crc32.h>
+#include <linux/lm_interface.h>
+#include <asm/uaccess.h>
+
+#include "gfs2.h"
+#include "incore.h"
+#include "bmap.h"
+#include "dir.h"
+#include "glock.h"
+#include "glops.h"
+#include "inode.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"
+#include "util.h"
+#include "eaops.h"
+
+/* For regular, non-NFS */
+struct filldir_reg {
+ struct gfs2_sbd *fdr_sbd;
+ int fdr_prefetch;
+
+ filldir_t fdr_filldir;
+ void *fdr_opaque;
+};
+
+/*
+ * Most fields left uninitialised to catch anybody who tries to
+ * use them. f_flags set to prevent file_accessed() from touching
+ * any other part of this. Its use is purely as a flag so that we
+ * know (in readpage()) whether or not do to locking.
+ */
+struct file gfs2_internal_file_sentinel = {
+ .f_flags = O_NOATIME|O_RDONLY,
+};
+
+static int gfs2_read_actor(read_descriptor_t *desc, struct page *page,
+ unsigned long offset, unsigned long size)
+{
+ char *kaddr;
+ unsigned long count = desc->count;
+
+ if (size > count)
+ size = count;
+
+ kaddr = kmap(page);
+ memcpy(desc->arg.buf, kaddr + offset, size);
+ kunmap(page);
+
+ desc->count = count - size;
+ desc->written += size;
+ desc->arg.buf += size;
+ return size;
+}
+
+int gfs2_internal_read(struct gfs2_inode *ip, struct file_ra_state *ra_state,
+ char *buf, loff_t *pos, unsigned size)
+{
+ struct inode *inode = &ip->i_inode;
+ read_descriptor_t desc;
+ desc.written = 0;
+ desc.arg.buf = buf;
+ desc.count = size;
+ desc.error = 0;
+ do_generic_mapping_read(inode->i_mapping, ra_state,
+ &gfs2_internal_file_sentinel, pos, &desc,
+ gfs2_read_actor);
+ return desc.written ? desc.written : desc.error;
+}
+
+/**
+ * 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 = GFS2_I(file->f_mapping->host);
+ struct gfs2_holder i_gh;
+ loff_t error;
+
+ 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;
+}
+
+/**
+ * filldir_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_func(void *opaque, const char *name, unsigned int length,
+ u64 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_addr, 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;
+}
+
+/**
+ * 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)
+{
+ struct inode *dir = file->f_mapping->host;
+ struct gfs2_inode *dip = GFS2_I(dir);
+ struct filldir_reg fdr;
+ struct gfs2_holder d_gh;
+ u64 offset = file->f_pos;
+ int error;
+
+ fdr.fdr_sbd = GFS2_SB(dir);
+ 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(dir, &offset, &fdr, filldir_func);
+
+ gfs2_glock_dq_uninit(&d_gh);
+
+ file->f_pos = offset;
+
+ return error;
+}
+
+/**
+ * fsflags_cvt
+ * @table: A table of 32 u32 flags
+ * @val: a 32 bit value to convert
+ *
+ * This function can be used to convert between fsflags values and
+ * GFS2's own flags values.
+ *
+ * Returns: the converted flags
+ */
+static u32 fsflags_cvt(const u32 *table, u32 val)
+{
+ u32 res = 0;
+ while(val) {
+ if (val & 1)
+ res |= *table;
+ table++;
+ val >>= 1;
+ }
+ return res;
+}
+
+static const u32 fsflags_to_gfs2[32] = {
+ [3] = GFS2_DIF_SYNC,
+ [4] = GFS2_DIF_IMMUTABLE,
+ [5] = GFS2_DIF_APPENDONLY,
+ [7] = GFS2_DIF_NOATIME,
+ [12] = GFS2_DIF_EXHASH,
+ [14] = GFS2_DIF_JDATA,
+ [20] = GFS2_DIF_DIRECTIO,
+};
+
+static const u32 gfs2_to_fsflags[32] = {
+ [gfs2fl_Sync] = FS_SYNC_FL,
+ [gfs2fl_Immutable] = FS_IMMUTABLE_FL,
+ [gfs2fl_AppendOnly] = FS_APPEND_FL,
+ [gfs2fl_NoAtime] = FS_NOATIME_FL,
+ [gfs2fl_ExHash] = FS_INDEX_FL,
+ [gfs2fl_Jdata] = FS_JOURNAL_DATA_FL,
+ [gfs2fl_Directio] = FS_DIRECTIO_FL,
+ [gfs2fl_InheritDirectio] = FS_DIRECTIO_FL,
+ [gfs2fl_InheritJdata] = FS_JOURNAL_DATA_FL,
+};
+
+static int gfs2_get_flags(struct file *filp, u32 __user *ptr)
+{
+ struct inode *inode = filp->f_dentry->d_inode;
+ struct gfs2_inode *ip = GFS2_I(inode);
+ struct gfs2_holder gh;
+ int error;
+ u32 fsflags;
+
+ gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &gh);
+ error = gfs2_glock_nq_m_atime(1, &gh);
+ if (error)
+ return error;
+
+ fsflags = fsflags_cvt(gfs2_to_fsflags, ip->i_di.di_flags);
+ if (put_user(fsflags, ptr))
+ error = -EFAULT;
+
+ gfs2_glock_dq_m(1, &gh);
+ gfs2_holder_uninit(&gh);
+ return error;
+}
+
+/* Flags that can be set by user space */
+#define GFS2_FLAGS_USER_SET (GFS2_DIF_JDATA| \
+ GFS2_DIF_DIRECTIO| \
+ GFS2_DIF_IMMUTABLE| \
+ GFS2_DIF_APPENDONLY| \
+ GFS2_DIF_NOATIME| \
+ GFS2_DIF_SYNC| \
+ GFS2_DIF_SYSTEM| \
+ GFS2_DIF_INHERIT_DIRECTIO| \
+ GFS2_DIF_INHERIT_JDATA)
+
+/**
+ * gfs2_set_flags - set flags on an inode
+ * @inode: The inode
+ * @flags: The flags to set
+ * @mask: Indicates which flags are valid
+ *
+ */
+static int do_gfs2_set_flags(struct file *filp, u32 reqflags, u32 mask)
+{
+ struct inode *inode = filp->f_dentry->d_inode;
+ struct gfs2_inode *ip = GFS2_I(inode);
+ struct gfs2_sbd *sdp = GFS2_SB(inode);
+ struct buffer_head *bh;
+ struct gfs2_holder gh;
+ int error;
+ u32 new_flags, flags;
+
+ error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
+ if (error)
+ return error;
+
+ flags = ip->i_di.di_flags;
+ new_flags = (flags & ~mask) | (reqflags & mask);
+ if ((new_flags ^ flags) == 0)
+ goto out;
+
+ if (S_ISDIR(inode->i_mode)) {
+ if ((new_flags ^ flags) & GFS2_DIF_JDATA)
+ new_flags ^= (GFS2_DIF_JDATA|GFS2_DIF_INHERIT_JDATA);
+ if ((new_flags ^ flags) & GFS2_DIF_DIRECTIO)
+ new_flags ^= (GFS2_DIF_DIRECTIO|GFS2_DIF_INHERIT_DIRECTIO);
+ }
+
+ error = -EINVAL;
+ if ((new_flags ^ flags) & ~GFS2_FLAGS_USER_SET)
+ goto out;
+
+ error = -EPERM;
+ if (IS_IMMUTABLE(inode) && (new_flags & GFS2_DIF_IMMUTABLE))
+ goto out;
+ if (IS_APPEND(inode) && (new_flags & GFS2_DIF_APPENDONLY))
+ goto out;
+ if (((new_flags ^ flags) & GFS2_DIF_IMMUTABLE) &&
+ !capable(CAP_LINUX_IMMUTABLE))
+ goto out;
+ if (!IS_IMMUTABLE(inode)) {
+ error = permission(inode, MAY_WRITE, NULL);
+ if (error)
+ goto out;
+ }
+
+ error = gfs2_trans_begin(sdp, RES_DINODE, 0);
+ if (error)
+ goto out;
+ error = gfs2_meta_inode_buffer(ip, &bh);
+ if (error)
+ goto out_trans_end;
+ gfs2_trans_add_bh(ip->i_gl, bh, 1);
+ ip->i_di.di_flags = new_flags;
+ gfs2_dinode_out(&ip->i_di, bh->b_data);
+ brelse(bh);
+out_trans_end:
+ gfs2_trans_end(sdp);
+out:
+ gfs2_glock_dq_uninit(&gh);
+ return error;
+}
+
+static int gfs2_set_flags(struct file *filp, u32 __user *ptr)
+{
+ u32 fsflags, gfsflags;
+ if (get_user(fsflags, ptr))
+ return -EFAULT;
+ gfsflags = fsflags_cvt(fsflags_to_gfs2, fsflags);
+ return do_gfs2_set_flags(filp, gfsflags, ~0);
+}
+
+static long gfs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+{
+ switch(cmd) {
+ case FS_IOC_GETFLAGS:
+ return gfs2_get_flags(filp, (u32 __user *)arg);
+ case FS_IOC_SETFLAGS:
+ return gfs2_set_flags(filp, (u32 __user *)arg);
+ }
+ 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 = GFS2_I(file->f_mapping->host);
+ struct gfs2_holder i_gh;
+ int error;
+
+ 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;
+ }
+
+ /* 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 = GFS2_I(inode);
+ struct gfs2_holder i_gh;
+ struct gfs2_file *fp;
+ int error;
+
+ fp = kzalloc(sizeof(struct gfs2_file), GFP_KERNEL);
+ if (!fp)
+ return -ENOMEM;
+
+ mutex_init(&fp->f_fl_mutex);
+
+ gfs2_assert_warn(GFS2_SB(inode), !file->private_data);
+ file->private_data = 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;
+
+ gfs2_glock_dq_uninit(&i_gh);
+ }
+
+ return 0;
+
+fail_gunlock:
+ gfs2_glock_dq_uninit(&i_gh);
+fail:
+ file->private_data = 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 = inode->i_sb->s_fs_info;
+ struct gfs2_file *fp;
+
+ fp = file->private_data;
+ file->private_data = 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 = GFS2_I(dentry->d_inode);
+
+ gfs2_log_flush(ip->i_gl->gl_sbd, 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 = GFS2_I(file->f_mapping->host);
+ struct gfs2_sbd *sdp = GFS2_SB(file->f_mapping->host);
+ struct lm_lockname name =
+ { .ln_number = ip->i_num.no_addr,
+ .ln_type = LM_TYPE_PLOCK };
+
+ 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;
+ int ret;
+ ret = posix_test_lock(file, fl, &tmp);
+ fl->fl_type = F_UNLCK;
+ if (ret)
+ memcpy(fl, &tmp, sizeof(struct file_lock));
+ return 0;
+ } else {
+ return posix_lock_file_wait(file, fl);
+ }
+ }
+
+ 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);
+}
+
+static int do_flock(struct file *file, int cmd, struct file_lock *fl)
+{
+ struct gfs2_file *fp = file->private_data;
+ struct gfs2_holder *fl_gh = &fp->f_fl_gh;
+ struct gfs2_inode *ip = GFS2_I(file->f_dentry->d_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;
+
+ mutex_lock(&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(GFS2_SB(&ip->i_inode),
+ 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(GFS2_SB(&ip->i_inode), !error);
+ }
+
+out:
+ mutex_unlock(&fp->f_fl_mutex);
+ return error;
+}
+
+static void do_unflock(struct file *file, struct file_lock *fl)
+{
+ struct gfs2_file *fp = file->private_data;
+ struct gfs2_holder *fl_gh = &fp->f_fl_gh;
+
+ mutex_lock(&fp->f_fl_mutex);
+ flock_lock_file_wait(file, fl);
+ if (fl_gh->gh_gl)
+ gfs2_glock_dq_uninit(fl_gh);
+ mutex_unlock(&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 = GFS2_I(file->f_mapping->host);
+ struct gfs2_sbd *sdp = GFS2_SB(file->f_mapping->host);
+
+ 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);
+ }
+}
+
+const struct file_operations gfs2_file_fops = {
+ .llseek = gfs2_llseek,
+ .read = do_sync_read,
+ .aio_read = generic_file_aio_read,
+ .write = do_sync_write,
+ .aio_write = generic_file_aio_write,
+ .unlocked_ioctl = gfs2_ioctl,
+ .mmap = gfs2_mmap,
+ .open = gfs2_open,
+ .release = gfs2_close,
+ .fsync = gfs2_fsync,
+ .lock = gfs2_lock,
+ .sendfile = generic_file_sendfile,
+ .flock = gfs2_flock,
+ .splice_read = generic_file_splice_read,
+ .splice_write = generic_file_splice_write,
+};
+
+const struct file_operations gfs2_dir_fops = {
+ .readdir = gfs2_readdir,
+ .unlocked_ioctl = gfs2_ioctl,
+ .open = gfs2_open,
+ .release = gfs2_close,
+ .fsync = gfs2_fsync,
+ .lock = gfs2_lock,
+ .flock = gfs2_flock,
+};
+
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-21 14:48:34 +0000