/* * High-level sync()-related operations */#include <linux/kernel.h>#include <linux/file.h>#include <linux/fs.h>#include <linux/module.h>#include <linux/sched.h>#include <linux/writeback.h>#include <linux/syscalls.h>#include <linux/linkage.h>#include <linux/pagemap.h>#include <linux/quotaops.h>#include <linux/buffer_head.h>#define VALID_FLAGS (SYNC_FILE_RANGE_WAIT_BEFORE|SYNC_FILE_RANGE_WRITE| \ SYNC_FILE_RANGE_WAIT_AFTER)/* * sync everything. Start out by waking pdflush, because that writes back * all queues in parallel. */static void do_sync(unsigned long wait){ wakeup_pdflush(0); sync_inodes(0); /* All mappings, inodes and their blockdevs */ DQUOT_SYNC(NULL); sync_supers(); /* Write the superblocks */ sync_filesystems(0); /* Start syncing the filesystems */ sync_filesystems(wait); /* Waitingly sync the filesystems */ sync_inodes(wait); /* Mappings, inodes and blockdevs, again. */ if (!wait) printk("Emergency Sync complete\n"); if (unlikely(laptop_mode)) laptop_sync_completion();}asmlinkage long sys_sync(void){ do_sync(1); return 0;}void emergency_sync(void){ pdflush_operation(do_sync, 0);}/* * Generic function to fsync a file. * * filp may be NULL if called via the msync of a vma. */int file_fsync(struct file *filp, struct dentry *dentry, int datasync){ struct inode * inode = dentry->d_inode; struct super_block * sb; int ret, err; /* sync the inode to buffers */ ret = write_inode_now(inode, 0); /* sync the superblock to buffers */ sb = inode->i_sb; lock_super(sb); if (sb->s_op->write_super) sb->s_op->write_super(sb); unlock_super(sb); /* .. finally sync the buffers to disk */ err = sync_blockdev(sb->s_bdev); if (!ret) ret = err; return ret;}long do_fsync(struct file *file, int datasync){ int ret; int err; struct address_space *mapping = file->f_mapping; if (!file->f_op || !file->f_op->fsync) { /* Why? We can still call filemap_fdatawrite */ ret = -EINVAL; goto out; } ret = filemap_fdatawrite(mapping); /* * We need to protect against concurrent writers, which could cause * livelocks in fsync_buffers_list(). */ mutex_lock(&mapping->host->i_mutex); err = file->f_op->fsync(file, file->f_path.dentry, datasync); if (!ret) ret = err; mutex_unlock(&mapping->host->i_mutex); err = filemap_fdatawait(mapping); if (!ret) ret = err;out: return ret;}static long __do_fsync(unsigned int fd, int datasync){ struct file *file; int ret = -EBADF; file = fget(fd); if (file) { ret = do_fsync(file, datasync); fput(file); } return ret;}asmlinkage long sys_fsync(unsigned int fd){ return __do_fsync(fd, 0);}asmlinkage long sys_fdatasync(unsigned int fd){ return __do_fsync(fd, 1);}/* * sys_sync_file_range() permits finely controlled syncing over a segment of * a file in the range offset .. (offset+nbytes-1) inclusive. If nbytes is * zero then sys_sync_file_range() will operate from offset out to EOF. * * The flag bits are: * * SYNC_FILE_RANGE_WAIT_BEFORE: wait upon writeout of all pages in the range * before performing the write. * * SYNC_FILE_RANGE_WRITE: initiate writeout of all those dirty pages in the * range which are not presently under writeback. * * SYNC_FILE_RANGE_WAIT_AFTER: wait upon writeout of all pages in the range * after performing the write. * * Useful combinations of the flag bits are: * * SYNC_FILE_RANGE_WAIT_BEFORE|SYNC_FILE_RANGE_WRITE: ensures that all pages * in the range which were dirty on entry to sys_sync_file_range() are placed * under writeout. This is a start-write-for-data-integrity operation. * * SYNC_FILE_RANGE_WRITE: start writeout of all dirty pages in the range which * are not presently under writeout. This is an asynchronous flush-to-disk * operation. Not suitable for data integrity operations. * * SYNC_FILE_RANGE_WAIT_BEFORE (or SYNC_FILE_RANGE_WAIT_AFTER): wait for * completion of writeout of all pages in the range. This will be used after an * earlier SYNC_FILE_RANGE_WAIT_BEFORE|SYNC_FILE_RANGE_WRITE operation to wait * for that operation to complete and to return the result. * * SYNC_FILE_RANGE_WAIT_BEFORE|SYNC_FILE_RANGE_WRITE|SYNC_FILE_RANGE_WAIT_AFTER: * a traditional sync() operation. This is a write-for-data-integrity operation * which will ensure that all pages in the range which were dirty on entry to * sys_sync_file_range() are committed to disk. * * * SYNC_FILE_RANGE_WAIT_BEFORE and SYNC_FILE_RANGE_WAIT_AFTER will detect any * I/O errors or ENOSPC conditions and will return those to the caller, after * clearing the EIO and ENOSPC flags in the address_space. * * It should be noted that none of these operations write out the file's * metadata. So unless the application is strictly performing overwrites of * already-instantiated disk blocks, there are no guarantees here that the data * will be available after a crash. */asmlinkage long sys_sync_file_range(int fd, loff_t offset, loff_t nbytes, unsigned int flags){ int ret; struct file *file; loff_t endbyte; /* inclusive */ int fput_needed; umode_t i_mode; ret = -EINVAL; if (flags & ~VALID_FLAGS) goto out; endbyte = offset + nbytes; if ((s64)offset < 0) goto out; if ((s64)endbyte < 0) goto out; if (endbyte < offset) goto out; if (sizeof(pgoff_t) == 4) { if (offset >= (0x100000000ULL << PAGE_CACHE_SHIFT)) { /* * The range starts outside a 32 bit machine's * pagecache addressing capabilities. Let it "succeed" */ ret = 0; goto out; } if (endbyte >= (0x100000000ULL << PAGE_CACHE_SHIFT)) { /* * Out to EOF */ nbytes = 0; } } if (nbytes == 0) endbyte = LLONG_MAX; else endbyte--; /* inclusive */ ret = -EBADF; file = fget_light(fd, &fput_needed); if (!file) goto out; i_mode = file->f_path.dentry->d_inode->i_mode; ret = -ESPIPE; if (!S_ISREG(i_mode) && !S_ISBLK(i_mode) && !S_ISDIR(i_mode) && !S_ISLNK(i_mode)) goto out_put; ret = do_sync_file_range(file, offset, endbyte, flags);out_put: fput_light(file, fput_needed);out: return ret;}/* * `endbyte' is inclusive */int do_sync_file_range(struct file *file, loff_t offset, loff_t endbyte, unsigned int flags){ int ret; struct address_space *mapping; mapping = file->f_mapping; if (!mapping) { ret = -EINVAL; goto out; } ret = 0; if (flags & SYNC_FILE_RANGE_WAIT_BEFORE) { ret = wait_on_page_writeback_range(mapping, offset >> PAGE_CACHE_SHIFT, endbyte >> PAGE_CACHE_SHIFT); if (ret < 0) goto out; } if (flags & SYNC_FILE_RANGE_WRITE) { ret = __filemap_fdatawrite_range(mapping, offset, endbyte, WB_SYNC_NONE); if (ret < 0) goto out; } if (flags & SYNC_FILE_RANGE_WAIT_AFTER) { ret = wait_on_page_writeback_range(mapping, offset >> PAGE_CACHE_SHIFT, endbyte >> PAGE_CACHE_SHIFT); }out: return ret;}EXPORT_SYMBOL_GPL(do_sync_file_range);
/*
* High-level sync()-related operations
*/
#include <linux/kernel.h>
#include <linux/file.h>
#include <linux/fs.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/writeback.h>
#include <linux/syscalls.h>
#include <linux/linkage.h>
#include <linux/pagemap.h>
#include <linux/quotaops.h>
#include <linux/buffer_head.h>
#define VALID_FLAGS (SYNC_FILE_RANGE_WAIT_BEFORE|SYNC_FILE_RANGE_WRITE| \
SYNC_FILE_RANGE_WAIT_AFTER)
/*
* sync everything. Start out by waking pdflush, because that writes back
* all queues in parallel.
*/
static void do_sync(unsigned long wait)
{
wakeup_pdflush(0);
sync_inodes(0); /* All mappings, inodes and their blockdevs */
DQUOT_SYNC(NULL);
sync_supers(); /* Write the superblocks */
sync_filesystems(0); /* Start syncing the filesystems */
sync_filesystems(wait); /* Waitingly sync the filesystems */
sync_inodes(wait); /* Mappings, inodes and blockdevs, again. */
if (!wait)
printk("Emergency Sync complete\n");
if (unlikely(laptop_mode))
laptop_sync_completion();
}
asmlinkage long sys_sync(void)
{
do_sync(1);
return 0;
}
void emergency_sync(void)
{
pdflush_operation(do_sync, 0);
}
/*
* Generic function to fsync a file.
*
* filp may be NULL if called via the msync of a vma.
*/
int file_fsync(struct file *filp, struct dentry *dentry, int datasync)
{
struct inode * inode = dentry->d_inode;
struct super_block * sb;
int ret, err;
/* sync the inode to buffers */
ret = write_inode_now(inode, 0);
/* sync the superblock to buffers */
sb = inode->i_sb;
lock_super(sb);
if (sb->s_op->write_super)
sb->s_op->write_super(sb);
unlock_super(sb);
/* .. finally sync the buffers to disk */
err = sync_blockdev(sb->s_bdev);
if (!ret)
ret = err;
return ret;
}
long do_fsync(struct file *file, int datasync)
{
int ret;
int err;
struct address_space *mapping = file->f_mapping;
if (!file->f_op || !file->f_op->fsync) {
/* Why? We can still call filemap_fdatawrite */
ret = -EINVAL;
goto out;
}
ret = filemap_fdatawrite(mapping);
/*
* We need to protect against concurrent writers, which could cause
* livelocks in fsync_buffers_list().
*/
mutex_lock(&mapping->host->i_mutex);
err = file->f_op->fsync(file, file->f_path.dentry, datasync);
if (!ret)
ret = err;
mutex_unlock(&mapping->host->i_mutex);
err = filemap_fdatawait(mapping);
if (!ret)
ret = err;
out:
return ret;
}
static long __do_fsync(unsigned int fd, int datasync)
{
struct file *file;
int ret = -EBADF;
file = fget(fd);
if (file) {
ret = do_fsync(file, datasync);
fput(file);
}
return ret;
}
asmlinkage long sys_fsync(unsigned int fd)
{
return __do_fsync(fd, 0);
}
asmlinkage long sys_fdatasync(unsigned int fd)
{
return __do_fsync(fd, 1);
}
/*
* sys_sync_file_range() permits finely controlled syncing over a segment of
* a file in the range offset .. (offset+nbytes-1) inclusive. If nbytes is
* zero then sys_sync_file_range() will operate from offset out to EOF.
*
* The flag bits are:
*
* SYNC_FILE_RANGE_WAIT_BEFORE: wait upon writeout of all pages in the range
* before performing the write.
*
* SYNC_FILE_RANGE_WRITE: initiate writeout of all those dirty pages in the
* range which are not presently under writeback.
*
* SYNC_FILE_RANGE_WAIT_AFTER: wait upon writeout of all pages in the range
* after performing the write.
*
* Useful combinations of the flag bits are:
*
* SYNC_FILE_RANGE_WAIT_BEFORE|SYNC_FILE_RANGE_WRITE: ensures that all pages
* in the range which were dirty on entry to sys_sync_file_range() are placed
* under writeout. This is a start-write-for-data-integrity operation.
*
* SYNC_FILE_RANGE_WRITE: start writeout of all dirty pages in the range which
* are not presently under writeout. This is an asynchronous flush-to-disk
* operation. Not suitable for data integrity operations.
*
* SYNC_FILE_RANGE_WAIT_BEFORE (or SYNC_FILE_RANGE_WAIT_AFTER): wait for
* completion of writeout of all pages in the range. This will be used after an
* earlier SYNC_FILE_RANGE_WAIT_BEFORE|SYNC_FILE_RANGE_WRITE operation to wait
* for that operation to complete and to return the result.
*
* SYNC_FILE_RANGE_WAIT_BEFORE|SYNC_FILE_RANGE_WRITE|SYNC_FILE_RANGE_WAIT_AFTER:
* a traditional sync() operation. This is a write-for-data-integrity operation
* which will ensure that all pages in the range which were dirty on entry to
* sys_sync_file_range() are committed to disk.
*
*
* SYNC_FILE_RANGE_WAIT_BEFORE and SYNC_FILE_RANGE_WAIT_AFTER will detect any
* I/O errors or ENOSPC conditions and will return those to the caller, after
* clearing the EIO and ENOSPC flags in the address_space.
*
* It should be noted that none of these operations write out the file's
* metadata. So unless the application is strictly performing overwrites of
* already-instantiated disk blocks, there are no guarantees here that the data
* will be available after a crash.
*/
asmlinkage long sys_sync_file_range(int fd, loff_t offset, loff_t nbytes,
unsigned int flags)
{
int ret;
struct file *file;
loff_t endbyte; /* inclusive */
int fput_needed;
umode_t i_mode;
ret = -EINVAL;
if (flags & ~VALID_FLAGS)
goto out;
endbyte = offset + nbytes;
if ((s64)offset < 0)
goto out;
if ((s64)endbyte < 0)
goto out;
if (endbyte < offset)
goto out;
if (sizeof(pgoff_t) == 4) {
if (offset >= (0x100000000ULL << PAGE_CACHE_SHIFT)) {
/*
* The range starts outside a 32 bit machine's
* pagecache addressing capabilities. Let it "succeed"
*/
ret = 0;
goto out;
}
if (endbyte >= (0x100000000ULL << PAGE_CACHE_SHIFT)) {
/*
* Out to EOF
*/
nbytes = 0;
}
}
if (nbytes == 0)
endbyte = LLONG_MAX;
else
endbyte--; /* inclusive */
ret = -EBADF;
file = fget_light(fd, &fput_needed);
if (!file)
goto out;
i_mode = file->f_path.dentry->d_inode->i_mode;
ret = -ESPIPE;
if (!S_ISREG(i_mode) && !S_ISBLK(i_mode) && !S_ISDIR(i_mode) &&
!S_ISLNK(i_mode))
goto out_put;
ret = do_sync_file_range(file, offset, endbyte, flags);
out_put:
fput_light(file, fput_needed);
out:
return ret;
}
/*
* `endbyte' is inclusive
*/
int do_sync_file_range(struct file *file, loff_t offset, loff_t endbyte,
unsigned int flags)
{
int ret;
struct address_space *mapping;
mapping = file->f_mapping;
if (!mapping) {
ret = -EINVAL;
goto out;
}
ret = 0;
if (flags & SYNC_FILE_RANGE_WAIT_BEFORE) {
ret = wait_on_page_writeback_range(mapping,
offset >> PAGE_CACHE_SHIFT,
endbyte >> PAGE_CACHE_SHIFT);
if (ret < 0)
goto out;
}
if (flags & SYNC_FILE_RANGE_WRITE) {
ret = __filemap_fdatawrite_range(mapping, offset, endbyte,
WB_SYNC_NONE);
if (ret < 0)
goto out;
}
if (flags & SYNC_FILE_RANGE_WAIT_AFTER) {
ret = wait_on_page_writeback_range(mapping,
offset >> PAGE_CACHE_SHIFT,
endbyte >> PAGE_CACHE_SHIFT);
}
out:
return ret;
}
EXPORT_SYMBOL_GPL(do_sync_file_range);