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Diffstat (limited to 'fs/cifs/file.c')
-rw-r--r--fs/cifs/file.c102
1 files changed, 69 insertions, 33 deletions
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index b691b893a848..b1e1fc6a6e6a 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -644,10 +644,10 @@ int cifs_lock(struct file *file, int cmd, struct file_lock *pfLock)
__u64 length;
bool wait_flag = false;
struct cifs_sb_info *cifs_sb;
- struct cifsTconInfo *pTcon;
+ struct cifsTconInfo *tcon;
__u16 netfid;
__u8 lockType = LOCKING_ANDX_LARGE_FILES;
- bool posix_locking;
+ bool posix_locking = 0;
length = 1 + pfLock->fl_end - pfLock->fl_start;
rc = -EACCES;
@@ -698,7 +698,7 @@ int cifs_lock(struct file *file, int cmd, struct file_lock *pfLock)
cFYI(1, ("Unknown type of lock"));
cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
- pTcon = cifs_sb->tcon;
+ tcon = cifs_sb->tcon;
if (file->private_data == NULL) {
FreeXid(xid);
@@ -706,9 +706,10 @@ int cifs_lock(struct file *file, int cmd, struct file_lock *pfLock)
}
netfid = ((struct cifsFileInfo *)file->private_data)->netfid;
- posix_locking = (cifs_sb->tcon->ses->capabilities & CAP_UNIX) &&
- (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(cifs_sb->tcon->fsUnixInfo.Capability));
-
+ if ((tcon->ses->capabilities & CAP_UNIX) &&
+ (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) &&
+ ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0))
+ posix_locking = 1;
/* BB add code here to normalize offset and length to
account for negative length which we can not accept over the
wire */
@@ -719,7 +720,7 @@ int cifs_lock(struct file *file, int cmd, struct file_lock *pfLock)
posix_lock_type = CIFS_RDLCK;
else
posix_lock_type = CIFS_WRLCK;
- rc = CIFSSMBPosixLock(xid, pTcon, netfid, 1 /* get */,
+ rc = CIFSSMBPosixLock(xid, tcon, netfid, 1 /* get */,
length, pfLock,
posix_lock_type, wait_flag);
FreeXid(xid);
@@ -727,10 +728,10 @@ int cifs_lock(struct file *file, int cmd, struct file_lock *pfLock)
}
/* BB we could chain these into one lock request BB */
- rc = CIFSSMBLock(xid, pTcon, netfid, length, pfLock->fl_start,
+ rc = CIFSSMBLock(xid, tcon, netfid, length, pfLock->fl_start,
0, 1, lockType, 0 /* wait flag */ );
if (rc == 0) {
- rc = CIFSSMBLock(xid, pTcon, netfid, length,
+ rc = CIFSSMBLock(xid, tcon, netfid, length,
pfLock->fl_start, 1 /* numUnlock */ ,
0 /* numLock */ , lockType,
0 /* wait flag */ );
@@ -767,7 +768,7 @@ int cifs_lock(struct file *file, int cmd, struct file_lock *pfLock)
if (numUnlock == 1)
posix_lock_type = CIFS_UNLCK;
- rc = CIFSSMBPosixLock(xid, pTcon, netfid, 0 /* set */,
+ rc = CIFSSMBPosixLock(xid, tcon, netfid, 0 /* set */,
length, pfLock,
posix_lock_type, wait_flag);
} else {
@@ -775,7 +776,7 @@ int cifs_lock(struct file *file, int cmd, struct file_lock *pfLock)
(struct cifsFileInfo *)file->private_data;
if (numLock) {
- rc = CIFSSMBLock(xid, pTcon, netfid, length,
+ rc = CIFSSMBLock(xid, tcon, netfid, length,
pfLock->fl_start,
0, numLock, lockType, wait_flag);
@@ -796,7 +797,7 @@ int cifs_lock(struct file *file, int cmd, struct file_lock *pfLock)
if (pfLock->fl_start <= li->offset &&
(pfLock->fl_start + length) >=
(li->offset + li->length)) {
- stored_rc = CIFSSMBLock(xid, pTcon,
+ stored_rc = CIFSSMBLock(xid, tcon,
netfid,
li->length, li->offset,
1, 0, li->type, false);
@@ -1475,7 +1476,11 @@ static int cifs_write_end(struct file *file, struct address_space *mapping,
cFYI(1, ("write_end for page %p from pos %lld with %d bytes",
page, pos, copied));
- if (!PageUptodate(page) && copied == PAGE_CACHE_SIZE)
+ if (PageChecked(page)) {
+ if (copied == len)
+ SetPageUptodate(page);
+ ClearPageChecked(page);
+ } else if (!PageUptodate(page) && copied == PAGE_CACHE_SIZE)
SetPageUptodate(page);
if (!PageUptodate(page)) {
@@ -2062,39 +2067,70 @@ static int cifs_write_begin(struct file *file, struct address_space *mapping,
{
pgoff_t index = pos >> PAGE_CACHE_SHIFT;
loff_t offset = pos & (PAGE_CACHE_SIZE - 1);
+ loff_t page_start = pos & PAGE_MASK;
+ loff_t i_size;
+ struct page *page;
+ int rc = 0;
cFYI(1, ("write_begin from %lld len %d", (long long)pos, len));
- *pagep = __grab_cache_page(mapping, index);
- if (!*pagep)
- return -ENOMEM;
-
- if (PageUptodate(*pagep))
- return 0;
+ page = __grab_cache_page(mapping, index);
+ if (!page) {
+ rc = -ENOMEM;
+ goto out;
+ }
- /* If we are writing a full page it will be up to date,
- no need to read from the server */
- if (len == PAGE_CACHE_SIZE && flags & AOP_FLAG_UNINTERRUPTIBLE)
- return 0;
+ if (PageUptodate(page))
+ goto out;
- if ((file->f_flags & O_ACCMODE) != O_WRONLY) {
- int rc;
+ /*
+ * If we write a full page it will be up to date, no need to read from
+ * the server. If the write is short, we'll end up doing a sync write
+ * instead.
+ */
+ if (len == PAGE_CACHE_SIZE)
+ goto out;
- /* might as well read a page, it is fast enough */
- rc = cifs_readpage_worker(file, *pagep, &offset);
+ /*
+ * optimize away the read when we have an oplock, and we're not
+ * expecting to use any of the data we'd be reading in. That
+ * is, when the page lies beyond the EOF, or straddles the EOF
+ * and the write will cover all of the existing data.
+ */
+ if (CIFS_I(mapping->host)->clientCanCacheRead) {
+ i_size = i_size_read(mapping->host);
+ if (page_start >= i_size ||
+ (offset == 0 && (pos + len) >= i_size)) {
+ zero_user_segments(page, 0, offset,
+ offset + len,
+ PAGE_CACHE_SIZE);
+ /*
+ * PageChecked means that the parts of the page
+ * to which we're not writing are considered up
+ * to date. Once the data is copied to the
+ * page, it can be set uptodate.
+ */
+ SetPageChecked(page);
+ goto out;
+ }
+ }
- /* we do not need to pass errors back
- e.g. if we do not have read access to the file
- because cifs_write_end will attempt synchronous writes
- -- shaggy */
+ if ((file->f_flags & O_ACCMODE) != O_WRONLY) {
+ /*
+ * might as well read a page, it is fast enough. If we get
+ * an error, we don't need to return it. cifs_write_end will
+ * do a sync write instead since PG_uptodate isn't set.
+ */
+ cifs_readpage_worker(file, page, &page_start);
} else {
/* we could try using another file handle if there is one -
but how would we lock it to prevent close of that handle
racing with this read? In any case
this will be written out by write_end so is fine */
}
-
- return 0;
+out:
+ *pagep = page;
+ return rc;
}
const struct address_space_operations cifs_addr_ops = {