diff options
Diffstat (limited to 'fs/cifs/cifssmb.c')
| -rw-r--r-- | fs/cifs/cifssmb.c | 42 |
1 files changed, 35 insertions, 7 deletions
diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c index da2f5446fa7a..3a75ee5a6b33 100644 --- a/fs/cifs/cifssmb.c +++ b/fs/cifs/cifssmb.c @@ -89,6 +89,32 @@ static struct { /* Forward declarations */ static void cifs_readv_complete(struct work_struct *work); +#ifdef CONFIG_HIGHMEM +/* + * On arches that have high memory, kmap address space is limited. By + * serializing the kmap operations on those arches, we ensure that we don't + * end up with a bunch of threads in writeback with partially mapped page + * arrays, stuck waiting for kmap to come back. That situation prevents + * progress and can deadlock. + */ +static DEFINE_MUTEX(cifs_kmap_mutex); + +static inline void +cifs_kmap_lock(void) +{ + mutex_lock(&cifs_kmap_mutex); +} + +static inline void +cifs_kmap_unlock(void) +{ + mutex_unlock(&cifs_kmap_mutex); +} +#else /* !CONFIG_HIGHMEM */ +#define cifs_kmap_lock() do { ; } while(0) +#define cifs_kmap_unlock() do { ; } while(0) +#endif /* CONFIG_HIGHMEM */ + /* Mark as invalid, all open files on tree connections since they were closed when session to server was lost */ static void mark_open_files_invalid(struct cifs_tcon *pTcon) @@ -1557,6 +1583,7 @@ cifs_readv_receive(struct TCP_Server_Info *server, struct mid_q_entry *mid) eof_index = eof ? (eof - 1) >> PAGE_CACHE_SHIFT : 0; cFYI(1, "eof=%llu eof_index=%lu", eof, eof_index); + cifs_kmap_lock(); list_for_each_entry_safe(page, tpage, &rdata->pages, lru) { if (remaining >= PAGE_CACHE_SIZE) { /* enough data to fill the page */ @@ -1606,6 +1633,7 @@ cifs_readv_receive(struct TCP_Server_Info *server, struct mid_q_entry *mid) page_cache_release(page); } } + cifs_kmap_unlock(); /* issue the read if we have any iovecs left to fill */ if (rdata->nr_iov > 1) { @@ -2194,7 +2222,9 @@ cifs_async_writev(struct cifs_writedata *wdata) * and set the iov_len properly for each one. It may also set * wdata->bytes too. */ + cifs_kmap_lock(); wdata->marshal_iov(iov, wdata); + cifs_kmap_unlock(); cFYI(1, "async write at %llu %u bytes", wdata->offset, wdata->bytes); @@ -4344,7 +4374,7 @@ int CIFSFindFirst(const int xid, struct cifs_tcon *tcon, const char *searchName, const struct nls_table *nls_codepage, - __u16 *pnetfid, + __u16 *pnetfid, __u16 search_flags, struct cifs_search_info *psrch_inf, int remap, const char dirsep) { /* level 257 SMB_ */ @@ -4416,8 +4446,7 @@ findFirstRetry: cpu_to_le16(ATTR_READONLY | ATTR_HIDDEN | ATTR_SYSTEM | ATTR_DIRECTORY); pSMB->SearchCount = cpu_to_le16(CIFSMaxBufSize/sizeof(FILE_UNIX_INFO)); - pSMB->SearchFlags = cpu_to_le16(CIFS_SEARCH_CLOSE_AT_END | - CIFS_SEARCH_RETURN_RESUME); + pSMB->SearchFlags = cpu_to_le16(search_flags); pSMB->InformationLevel = cpu_to_le16(psrch_inf->info_level); /* BB what should we set StorageType to? Does it matter? BB */ @@ -4487,8 +4516,8 @@ findFirstRetry: return rc; } -int CIFSFindNext(const int xid, struct cifs_tcon *tcon, - __u16 searchHandle, struct cifs_search_info *psrch_inf) +int CIFSFindNext(const int xid, struct cifs_tcon *tcon, __u16 searchHandle, + __u16 search_flags, struct cifs_search_info *psrch_inf) { TRANSACTION2_FNEXT_REQ *pSMB = NULL; TRANSACTION2_FNEXT_RSP *pSMBr = NULL; @@ -4531,8 +4560,7 @@ int CIFSFindNext(const int xid, struct cifs_tcon *tcon, cpu_to_le16(CIFSMaxBufSize / sizeof(FILE_UNIX_INFO)); pSMB->InformationLevel = cpu_to_le16(psrch_inf->info_level); pSMB->ResumeKey = psrch_inf->resume_key; - pSMB->SearchFlags = - cpu_to_le16(CIFS_SEARCH_CLOSE_AT_END | CIFS_SEARCH_RETURN_RESUME); + pSMB->SearchFlags = cpu_to_le16(search_flags); name_len = psrch_inf->resume_name_len; params += name_len; |