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-rw-r--r--fs/gfs2/ops_file.c982
1 files changed, 982 insertions, 0 deletions
diff --git a/fs/gfs2/ops_file.c b/fs/gfs2/ops_file.c
new file mode 100644
index 00000000000..26f1d3249b0
--- /dev/null
+++ b/fs/gfs2/ops_file.c
@@ -0,0 +1,982 @@
+/*
+ * 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 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/fs.h>
+#include <linux/gfs2_ondisk.h>
+#include <linux/ext2_fs.h>
+#include <linux/crc32.h>
+#include <linux/iflags.h>
+#include <asm/uaccess.h>
+
+#include "gfs2.h"
+#include "lm_interface.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"
+
+/* "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;
+};
+
+/*
+ * 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_sentinal = {
+ .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_sentinal, 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;
+}
+
+
+static ssize_t gfs2_direct_IO_read(struct kiocb *iocb, const struct iovec *iov,
+ loff_t offset, unsigned long nr_segs)
+{
+ struct file *file = iocb->ki_filp;
+ struct address_space *mapping = file->f_mapping;
+ ssize_t retval;
+
+ retval = filemap_write_and_wait(mapping);
+ if (retval == 0) {
+ retval = mapping->a_ops->direct_IO(READ, iocb, iov, offset,
+ nr_segs);
+ }
+ return retval;
+}
+
+/**
+ * __gfs2_file_aio_read - The main GFS2 read function
+ *
+ * N.B. This is almost, but not quite the same as __generic_file_aio_read()
+ * the important subtle different being that inode->i_size isn't valid
+ * unless we are holding a lock, and we do this _only_ on the O_DIRECT
+ * path since otherwise locking is done entirely at the page cache
+ * layer.
+ */
+static ssize_t __gfs2_file_aio_read(struct kiocb *iocb,
+ const struct iovec *iov,
+ unsigned long nr_segs, loff_t *ppos)
+{
+ struct file *filp = iocb->ki_filp;
+ struct gfs2_inode *ip = GFS2_I(filp->f_mapping->host);
+ struct gfs2_holder gh;
+ ssize_t retval;
+ unsigned long seg;
+ size_t count;
+
+ count = 0;
+ for (seg = 0; seg < nr_segs; seg++) {
+ const struct iovec *iv = &iov[seg];
+
+ /*
+ * If any segment has a negative length, or the cumulative
+ * length ever wraps negative then return -EINVAL.
+ */
+ count += iv->iov_len;
+ if (unlikely((ssize_t)(count|iv->iov_len) < 0))
+ return -EINVAL;
+ if (access_ok(VERIFY_WRITE, iv->iov_base, iv->iov_len))
+ continue;
+ if (seg == 0)
+ return -EFAULT;
+ nr_segs = seg;
+ count -= iv->iov_len; /* This segment is no good */
+ break;
+ }
+
+ /* coalesce the iovecs and go direct-to-BIO for O_DIRECT */
+ if (filp->f_flags & O_DIRECT) {
+ loff_t pos = *ppos, size;
+ struct address_space *mapping;
+ struct inode *inode;
+
+ mapping = filp->f_mapping;
+ inode = mapping->host;
+ retval = 0;
+ if (!count)
+ goto out; /* skip atime */
+
+ gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &gh);
+ retval = gfs2_glock_nq_m_atime(1, &gh);
+ if (retval)
+ goto out;
+ if (gfs2_is_stuffed(ip)) {
+ gfs2_glock_dq_m(1, &gh);
+ gfs2_holder_uninit(&gh);
+ goto fallback_to_normal;
+ }
+ size = i_size_read(inode);
+ if (pos < size) {
+ retval = gfs2_direct_IO_read(iocb, iov, pos, nr_segs);
+ if (retval > 0 && !is_sync_kiocb(iocb))
+ retval = -EIOCBQUEUED;
+ if (retval > 0)
+ *ppos = pos + retval;
+ }
+ file_accessed(filp);
+ gfs2_glock_dq_m(1, &gh);
+ gfs2_holder_uninit(&gh);
+ goto out;
+ }
+
+fallback_to_normal:
+ retval = 0;
+ if (count) {
+ for (seg = 0; seg < nr_segs; seg++) {
+ read_descriptor_t desc;
+
+ desc.written = 0;
+ desc.arg.buf = iov[seg].iov_base;
+ desc.count = iov[seg].iov_len;
+ if (desc.count == 0)
+ continue;
+ desc.error = 0;
+ do_generic_file_read(filp,ppos,&desc,file_read_actor);
+ retval += desc.written;
+ if (desc.error) {
+ retval = retval ?: desc.error;
+ break;
+ }
+ }
+ }
+out:
+ return retval;
+}
+
+/**
+ * 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 *filp, char __user *buf, size_t size,
+ loff_t *offset)
+{
+ struct iovec local_iov = { .iov_base = buf, .iov_len = size };
+ struct kiocb kiocb;
+ ssize_t ret;
+
+ init_sync_kiocb(&kiocb, filp);
+ ret = __gfs2_file_aio_read(&kiocb, &local_iov, 1, offset);
+ if (-EIOCBQUEUED == ret)
+ ret = wait_on_sync_kiocb(&kiocb);
+ return ret;
+}
+
+static ssize_t gfs2_file_readv(struct file *filp, const struct iovec *iov,
+ unsigned long nr_segs, loff_t *ppos)
+{
+ struct kiocb kiocb;
+ ssize_t ret;
+
+ init_sync_kiocb(&kiocb, filp);
+ ret = __gfs2_file_aio_read(&kiocb, iov, nr_segs, ppos);
+ if (-EIOCBQUEUED == ret)
+ ret = wait_on_sync_kiocb(&kiocb);
+ return ret;
+}
+
+static ssize_t gfs2_file_aio_read(struct kiocb *iocb, char __user *buf,
+ size_t count, loff_t pos)
+{
+ struct iovec local_iov = { .iov_base = buf, .iov_len = count };
+
+ BUG_ON(iocb->ki_pos != pos);
+ return __gfs2_file_aio_read(iocb, &local_iov, 1, &iocb->ki_pos);
+}
+
+
+/**
+ * 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_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;
+}
+
+/**
+ * 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 inode *dir = file->f_mapping->host;
+ struct gfs2_inode *dip = GFS2_I(dir);
+ struct filldir_reg fdr;
+ struct gfs2_holder d_gh;
+ uint64_t 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_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 inode *dir = file->f_mapping->host;
+ struct gfs2_inode *dip = GFS2_I(dir);
+ struct gfs2_sbd *sdp = GFS2_SB(dir);
+ 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(dir, &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;
+
+ if (strcmp(current->comm, "nfsd") != 0)
+ error = readdir_reg(file, dirent, filldir);
+ else
+ error = readdir_bad(file, dirent, filldir);
+
+ return error;
+}
+
+static const u32 iflags_to_gfs2[32] = {
+ [iflag_Sync] = GFS2_DIF_SYNC,
+ [iflag_Immutable] = GFS2_DIF_IMMUTABLE,
+ [iflag_Append] = GFS2_DIF_APPENDONLY,
+ [iflag_NoAtime] = GFS2_DIF_NOATIME,
+ [iflag_Index] = GFS2_DIF_EXHASH,
+ [iflag_JournalData] = GFS2_DIF_JDATA,
+ [iflag_DirectIO] = GFS2_DIF_DIRECTIO,
+};
+
+static const u32 gfs2_to_iflags[32] = {
+ [gfs2fl_Sync] = IFLAG_SYNC,
+ [gfs2fl_Immutable] = IFLAG_IMMUTABLE,
+ [gfs2fl_AppendOnly] = IFLAG_APPEND,
+ [gfs2fl_NoAtime] = IFLAG_NOATIME,
+ [gfs2fl_ExHash] = IFLAG_INDEX,
+ [gfs2fl_Jdata] = IFLAG_JOURNAL_DATA,
+ [gfs2fl_Directio] = IFLAG_DIRECTIO,
+ [gfs2fl_InheritDirectio] = IFLAG_DIRECTIO,
+ [gfs2fl_InheritJdata] = IFLAG_JOURNAL_DATA,
+};
+
+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 iflags;
+
+ gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &gh);
+ error = gfs2_glock_nq_m_atime(1, &gh);
+ if (error)
+ return error;
+
+ iflags = iflags_cvt(gfs2_to_iflags, ip->i_di.di_flags);
+ if (put_user(iflags, 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;
+
+ gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
+ error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
+ if (error) {
+ gfs2_holder_uninit(&gh);
+ 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 iflags, gfsflags;
+ if (get_user(iflags, ptr))
+ return -EFAULT;
+ gfsflags = iflags_cvt(iflags_to_gfs2, iflags);
+ return do_gfs2_set_flags(filp, gfsflags, ~0);
+}
+
+static long gfs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+{
+ switch(cmd) {
+ case IFLAGS_GET_IOC:
+ return gfs2_get_flags(filp, (u32 __user *)arg);
+ case IFLAGS_SET_IOC:
+ 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 = gfs2_read,
+ .readv = gfs2_file_readv,
+ .aio_read = gfs2_file_aio_read,
+ .write = generic_file_write,
+ .writev = generic_file_writev,
+ .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 2.25.1) at 2024-05-20 22:31:18 +0000