AFS: write support fixes

AFS write support fixes:

 (1) Support large files using the 64-bit file access operations if available
     on the server.

 (2) Use kmap_atomic() rather than kmap() in afs_prepare_page().

 (3) Don't do stuff in afs_writepage() that's done by the caller.

[akpm@linux-foundation.org: fix right shift count >= width of type]
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/fs/afs/afs_fs.h b/fs/afs/afs_fs.h
index 2198006..d963ef4 100644 (file)
--- a/fs/afs/afs_fs.h
+++ b/fs/afs/afs_fs.h
@@ -31,6 +31,8 @@ enum AFS_FS_Operations {
        FSGETVOLUMEINFO         = 148,  /* AFS Get root volume information */
        FSGETROOTVOLUME         = 151,  /* AFS Get root volume name */
        FSLOOKUP                = 161,  /* AFS lookup file in directory */
+       FSFETCHDATA64           = 65537, /* AFS Fetch file data */
+       FSSTOREDATA64           = 65538, /* AFS Store file data */
 };
 
 enum AFS_FS_Errors {

diff --git a/fs/afs/fsclient.c b/fs/afs/fsclient.c
index 025b190..56cc0ef 100644 (file)
--- a/fs/afs/fsclient.c
+++ b/fs/afs/fsclient.c
@@ -293,9 +293,33 @@ static int afs_deliver_fs_fetch_data(struct afs_call *call,
        case 0:
                call->offset = 0;
                call->unmarshall++;
+               if (call->operation_ID != FSFETCHDATA64) {
+                       call->unmarshall++;
+                       goto no_msw;
+               }
 
-               /* extract the returned data length */
+               /* extract the upper part of the returned data length of an
+                * FSFETCHDATA64 op (which should always be 0 using this
+                * client) */
        case 1:
+               _debug("extract data length (MSW)");
+               ret = afs_extract_data(call, skb, last, &call->tmp, 4);
+               switch (ret) {
+               case 0:         break;
+               case -EAGAIN:   return 0;
+               default:        return ret;
+               }
+
+               call->count = ntohl(call->tmp);
+               _debug("DATA length MSW: %u", call->count);
+               if (call->count > 0)
+                       return -EBADMSG;
+               call->offset = 0;
+               call->unmarshall++;
+
+       no_msw:
+               /* extract the returned data length */
+       case 2:
                _debug("extract data length");
                ret = afs_extract_data(call, skb, last, &call->tmp, 4);
                switch (ret) {
@@ -312,7 +336,7 @@ static int afs_deliver_fs_fetch_data(struct afs_call *call,
                call->unmarshall++;
 
                /* extract the returned data */
-       case 2:
+       case 3:
                _debug("extract data");
                if (call->count > 0) {
                        page = call->reply3;
@@ -331,7 +355,7 @@ static int afs_deliver_fs_fetch_data(struct afs_call *call,
                call->unmarshall++;
 
                /* extract the metadata */
-       case 3:
+       case 4:
                ret = afs_extract_data(call, skb, last, call->buffer,
                                       (21 + 3 + 6) * 4);
                switch (ret) {
@@ -349,7 +373,7 @@ static int afs_deliver_fs_fetch_data(struct afs_call *call,
                call->offset = 0;
                call->unmarshall++;
 
-       case 4:
+       case 5:
                _debug("trailer");
                if (skb->len != 0)
                        return -EBADMSG;
@@ -381,6 +405,56 @@ static const struct afs_call_type afs_RXFSFetchData = {
        .destructor     = afs_flat_call_destructor,
 };
 
+static const struct afs_call_type afs_RXFSFetchData64 = {
+       .name           = "FS.FetchData64",
+       .deliver        = afs_deliver_fs_fetch_data,
+       .abort_to_error = afs_abort_to_error,
+       .destructor     = afs_flat_call_destructor,
+};
+
+/*
+ * fetch data from a very large file
+ */
+static int afs_fs_fetch_data64(struct afs_server *server,
+                              struct key *key,
+                              struct afs_vnode *vnode,
+                              off_t offset, size_t length,
+                              struct page *buffer,
+                              const struct afs_wait_mode *wait_mode)
+{
+       struct afs_call *call;
+       __be32 *bp;
+
+       _enter("");
+
+       ASSERTCMP(length, <, ULONG_MAX);
+
+       call = afs_alloc_flat_call(&afs_RXFSFetchData64, 32, (21 + 3 + 6) * 4);
+       if (!call)
+               return -ENOMEM;
+
+       call->key = key;
+       call->reply = vnode;
+       call->reply2 = NULL; /* volsync */
+       call->reply3 = buffer;
+       call->service_id = FS_SERVICE;
+       call->port = htons(AFS_FS_PORT);
+       call->operation_ID = FSFETCHDATA64;
+
+       /* marshall the parameters */
+       bp = call->request;
+       bp[0] = htonl(FSFETCHDATA64);
+       bp[1] = htonl(vnode->fid.vid);
+       bp[2] = htonl(vnode->fid.vnode);
+       bp[3] = htonl(vnode->fid.unique);
+       bp[4] = htonl(upper_32_bits(offset));
+       bp[5] = htonl((u32) offset);
+       bp[6] = 0;
+       bp[7] = htonl((u32) length);
+
+       return afs_make_call(&server->addr, call, GFP_NOFS, wait_mode);
+}
+
 /*
  * fetch data from a file
  */
@@ -394,6 +468,10 @@ int afs_fs_fetch_data(struct afs_server *server,
        struct afs_call *call;
        __be32 *bp;
 
+       if (upper_32_bits(offset) || upper_32_bits(offset + length))
+               return afs_fs_fetch_data64(server, key, vnode, offset, length,
+                                          buffer, wait_mode);
+
        _enter("");
 
        call = afs_alloc_flat_call(&afs_RXFSFetchData, 24, (21 + 3 + 6) * 4);
@@ -406,6 +484,7 @@ int afs_fs_fetch_data(struct afs_server *server,
        call->reply3 = buffer;
        call->service_id = FS_SERVICE;
        call->port = htons(AFS_FS_PORT);
+       call->operation_ID = FSFETCHDATA;
 
        /* marshall the parameters */
        bp = call->request;
@@ -1032,6 +1111,73 @@ static const struct afs_call_type afs_RXFSStoreData = {
        .destructor     = afs_flat_call_destructor,
 };
 
+static const struct afs_call_type afs_RXFSStoreData64 = {
+       .name           = "FS.StoreData64",
+       .deliver        = afs_deliver_fs_store_data,
+       .abort_to_error = afs_abort_to_error,
+       .destructor     = afs_flat_call_destructor,
+};
+
+/*
+ * store a set of pages to a very large file
+ */
+static int afs_fs_store_data64(struct afs_server *server,
+                              struct afs_writeback *wb,
+                              pgoff_t first, pgoff_t last,
+                              unsigned offset, unsigned to,
+                              loff_t size, loff_t pos, loff_t i_size,
+                              const struct afs_wait_mode *wait_mode)
+{
+       struct afs_vnode *vnode = wb->vnode;
+       struct afs_call *call;
+       __be32 *bp;
+
+       _enter(",%x,{%x:%u},,",
+              key_serial(wb->key), vnode->fid.vid, vnode->fid.vnode);
+
+       call = afs_alloc_flat_call(&afs_RXFSStoreData64,
+                                  (4 + 6 + 3 * 2) * 4,
+                                  (21 + 6) * 4);
+       if (!call)
+               return -ENOMEM;
+
+       call->wb = wb;
+       call->key = wb->key;
+       call->reply = vnode;
+       call->service_id = FS_SERVICE;
+       call->port = htons(AFS_FS_PORT);
+       call->mapping = vnode->vfs_inode.i_mapping;
+       call->first = first;
+       call->last = last;
+       call->first_offset = offset;
+       call->last_to = to;
+       call->send_pages = true;
+       call->store_version = vnode->status.data_version + 1;
+
+       /* marshall the parameters */
+       bp = call->request;
+       *bp++ = htonl(FSSTOREDATA64);
+       *bp++ = htonl(vnode->fid.vid);
+       *bp++ = htonl(vnode->fid.vnode);
+       *bp++ = htonl(vnode->fid.unique);
+
+       *bp++ = 0; /* mask */
+       *bp++ = 0; /* mtime */
+       *bp++ = 0; /* owner */
+       *bp++ = 0; /* group */
+       *bp++ = 0; /* unix mode */
+       *bp++ = 0; /* segment size */
+
+       *bp++ = htonl(pos >> 32);
+       *bp++ = htonl((u32) pos);
+       *bp++ = htonl(size >> 32);
+       *bp++ = htonl((u32) size);
+       *bp++ = htonl(i_size >> 32);
+       *bp++ = htonl((u32) i_size);
+
+       return afs_make_call(&server->addr, call, GFP_NOFS, wait_mode);
+}
+
 /*
  * store a set of pages
  */
@@ -1062,7 +1208,9 @@ int afs_fs_store_data(struct afs_server *server, struct afs_writeback *wb,
               (unsigned long long) size, (unsigned long long) pos,
               (unsigned long long) i_size);
 
-       BUG_ON(i_size > 0xffffffff); // TODO: use 64-bit store
+       if (pos >> 32 || i_size >> 32 || size >> 32 || (pos + size) >> 32)
+               return afs_fs_store_data64(server, wb, first, last, offset, to,
+                                          size, pos, i_size, wait_mode);
 
        call = afs_alloc_flat_call(&afs_RXFSStoreData,
                                   (4 + 6 + 3) * 4,
@@ -1158,6 +1306,61 @@ static const struct afs_call_type afs_RXFSStoreData_as_Status = {
        .destructor     = afs_flat_call_destructor,
 };
 
+static const struct afs_call_type afs_RXFSStoreData64_as_Status = {
+       .name           = "FS.StoreData64",
+       .deliver        = afs_deliver_fs_store_status,
+       .abort_to_error = afs_abort_to_error,
+       .destructor     = afs_flat_call_destructor,
+};
+
+/*
+ * set the attributes on a very large file, using FS.StoreData rather than
+ * FS.StoreStatus so as to alter the file size also
+ */
+static int afs_fs_setattr_size64(struct afs_server *server, struct key *key,
+                                struct afs_vnode *vnode, struct iattr *attr,
+                                const struct afs_wait_mode *wait_mode)
+{
+       struct afs_call *call;
+       __be32 *bp;
+
+       _enter(",%x,{%x:%u},,",
+              key_serial(key), vnode->fid.vid, vnode->fid.vnode);
+
+       ASSERT(attr->ia_valid & ATTR_SIZE);
+
+       call = afs_alloc_flat_call(&afs_RXFSStoreData64_as_Status,
+                                  (4 + 6 + 3 * 2) * 4,
+                                  (21 + 6) * 4);
+       if (!call)
+               return -ENOMEM;
+
+       call->key = key;
+       call->reply = vnode;
+       call->service_id = FS_SERVICE;
+       call->port = htons(AFS_FS_PORT);
+       call->store_version = vnode->status.data_version + 1;
+       call->operation_ID = FSSTOREDATA;
+
+       /* marshall the parameters */
+       bp = call->request;
+       *bp++ = htonl(FSSTOREDATA64);
+       *bp++ = htonl(vnode->fid.vid);
+       *bp++ = htonl(vnode->fid.vnode);
+       *bp++ = htonl(vnode->fid.unique);
+
+       xdr_encode_AFS_StoreStatus(&bp, attr);
+
+       *bp++ = 0;                              /* position of start of write */
+       *bp++ = 0;
+       *bp++ = 0;                              /* size of write */
+       *bp++ = 0;
+       *bp++ = htonl(attr->ia_size >> 32);     /* new file length */
+       *bp++ = htonl((u32) attr->ia_size);
+
+       return afs_make_call(&server->addr, call, GFP_NOFS, wait_mode);
+}
+
 /*
  * set the attributes on a file, using FS.StoreData rather than FS.StoreStatus
  * so as to alter the file size also
@@ -1173,7 +1376,9 @@ static int afs_fs_setattr_size(struct afs_server *server, struct key *key,
               key_serial(key), vnode->fid.vid, vnode->fid.vnode);
 
        ASSERT(attr->ia_valid & ATTR_SIZE);
-       ASSERTCMP(attr->ia_size, <=, 0xffffffff); // TODO: use 64-bit store
+       if (attr->ia_size >> 32)
+               return afs_fs_setattr_size64(server, key, vnode, attr,
+                                            wait_mode);
 
        call = afs_alloc_flat_call(&afs_RXFSStoreData_as_Status,
                                   (4 + 6 + 3) * 4,

diff --git a/fs/afs/write.c b/fs/afs/write.c
index 83ff292..aa03d43 100644 (file)
--- a/fs/afs/write.c
+++ b/fs/afs/write.c
@@ -122,7 +122,7 @@ static int afs_prepare_page(struct afs_vnode *vnode, struct page *page,
        if (offset == 0 && to == PAGE_SIZE)
                return 0;
 
-       p = kmap(page);
+       p = kmap_atomic(page, KM_USER0);
 
        i_size = i_size_read(&vnode->vfs_inode);
        pos = (loff_t) page->index << PAGE_SHIFT;
@@ -133,7 +133,7 @@ static int afs_prepare_page(struct afs_vnode *vnode, struct page *page,
                        memset(p, 0, offset);
                if (to < PAGE_SIZE)
                        memset(p + to, 0, PAGE_SIZE - to);
-               kunmap(page);
+               kunmap_atomic(p, KM_USER0);
                return 0;
        }
 
@@ -152,7 +152,7 @@ static int afs_prepare_page(struct afs_vnode *vnode, struct page *page,
                        memset(p + eof, 0, PAGE_SIZE - eof);
        }
 
-       kunmap(p);
+       kunmap_atomic(p, KM_USER0);
 
        ret = 0;
        if (offset > 0 || eof > to) {
@@ -489,14 +489,6 @@ int afs_writepage(struct page *page, struct writeback_control *wbc)
 
        _enter("{%lx},", page->index);
 
-       if (wbc->sync_mode != WB_SYNC_NONE)
-               wait_on_page_writeback(page);
-
-       if (PageWriteback(page) || !PageDirty(page)) {
-               unlock_page(page);
-               return 0;
-       }
-
        wb = (struct afs_writeback *) page_private(page);
        ASSERT(wb != NULL);