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path: root/drivers/infiniband/core/umem.c
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2008-06-06IB/umem: Avoid sign problems when demoting npages to integerRoland Dreier
On a 64-bit architecture, if ib_umem_get() is called with a size value that is so big that npages is negative when cast to int, then the length of the page list passed to get_user_pages(), namely min_t(int, npages, PAGE_SIZE / sizeof (struct page *)) will be negative, and get_user_pages() will immediately return 0 (at least since 900cf086, "Be more robust about bad arguments in get_user_pages()"). This leads to an infinite loop in ib_umem_get(), since the code boils down to: while (npages) { ret = get_user_pages(...); npages -= ret; } Fix this by taking the minimum as unsigned longs, so that the value of npages is never truncated. The impact of this bug isn't too severe, since the value of npages is checked against RLIMIT_MEMLOCK, so a process would need to have an astronomical limit or have CAP_IPC_LOCK to be able to trigger this, and such a process could already cause lots of mischief. But it does let buggy userspace code cause a kernel lock-up; for example I hit this with code that passes a negative value into a memory registartion function where it is promoted to a huge u64 value. Cc: <stable@kernel.org> Signed-off-by: Roland Dreier <rolandd@cisco.com>
2008-04-29IB: expand ib_umem_get() prototypeArthur Kepner
Add a new parameter, dmasync, to the ib_umem_get() prototype. Use dmasync = 1 when mapping user-allocated CQs with ib_umem_get(). Signed-off-by: Arthur Kepner <akepner@sgi.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Jesse Barnes <jbarnes@virtuousgeek.org> Cc: Jes Sorensen <jes@sgi.com> Cc: Randy Dunlap <randy.dunlap@oracle.com> Cc: Roland Dreier <rdreier@cisco.com> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Cc: David Miller <davem@davemloft.net> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Grant Grundler <grundler@parisc-linux.org> Cc: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-24SG: Change sg_set_page() to take length and offset argumentJens Axboe
Most drivers need to set length and offset as well, so may as well fold those three lines into one. Add sg_assign_page() for those two locations that only needed to set the page, where the offset/length is set outside of the function context. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-10-22[SG] Update drivers to use sg helpersJens Axboe
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-10-09IB/umem: Add hugetlb flag to struct ib_umemJoachim Fenkes
During ib_umem_get(), determine whether all pages from the memory region are hugetlb pages and report this in the "hugetlb" member. Low-level drivers can use this information if they need it. Signed-off-by: Joachim Fenkes <fenkes@de.ibm.com> Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-08-03IB: Move the macro IB_UMEM_MAX_PAGE_CHUNK() to umem.cDotan Barak
After moving the definition of struct ib_umem_chunk from ib_verbs.h to ib_umem.h there isn't any reason for the macro IB_UMEM_MAX_PAGE_CHUNK to stay in ib_verbs.h. Move the macro to umem.c, the only place where it is used. Signed-off-by: Dotan Barak <dotanb@dev.mellanox.co.il> Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-07-09IB: Fix ib_umem_get() when npages == 0Andrew Morton
gcc correctly warned: drivers/infiniband/core/umem.c: In function 'ib_umem_get': drivers/infiniband/core/umem.c:78: warning: 'ret' may be used uninitialized in this function Set ret to 0 in case npages == 0 and the loop isn't entered at all. Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-06-21IB/umem: Fix possible hang on process exitRoland Dreier
If ib_umem_release() is called after ib_uverbs_close() sets context->closing, then a process can get stuck in a D state, because the code boils down to if (down_write_trylock(&mm->mmap_sem)) down_write(&mm->mmap_sem); which is obviously a stupid instant deadlock. Fix the code so that we only try to take the lock once. This bug was introduced in commit f7c6a7b5 ("IB/uverbs: Export ib_umem_get()/ib_umem_release() to modules") which fortunately never made it into a release, and was reported by Pete Wyckoff <pw@osc.edu>. Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-05-21Merge branch 'for-linus' of ↵Linus Torvalds
master.kernel.org:/pub/scm/linux/kernel/git/roland/infiniband * 'for-linus' of master.kernel.org:/pub/scm/linux/kernel/git/roland/infiniband: IB/cm: Improve local id allocation IPoIB/cm: Fix SRQ WR leak IB/ipoib: Fix typos in error messages IB/mlx4: Check if SRQ is full when posting receive IB/mlx4: Pass send queue sizes from userspace to kernel IB/mlx4: Fix check of opcode in mlx4_ib_post_send() mlx4_core: Fix array overrun in dump_dev_cap_flags() IB/mlx4: Fix RESET to RESET and RESET to ERROR transitions IB/mthca: Fix RESET to ERROR transition IB/mlx4: Set GRH:HopLimit when sending globally routed MADs IB/mthca: Set GRH:HopLimit when building MLX headers IB/mlx4: Fix check of max_qp_dest_rdma in modify QP IB/mthca: Fix use-after-free on device restart IB/ehca: Return proper error code if register_mr fails IPoIB: Handle P_Key table reordering IB/core: Use start_port() and end_port() IB/core: Add helpers for uncached GID and P_Key searches IB/ipath: Fix potential deadlock with multicast spinlocks IB/core: Free umem when mm is already gone
2007-05-21Detach sched.h from mm.hAlexey Dobriyan
First thing mm.h does is including sched.h solely for can_do_mlock() inline function which has "current" dereference inside. By dealing with can_do_mlock() mm.h can be detached from sched.h which is good. See below, why. This patch a) removes unconditional inclusion of sched.h from mm.h b) makes can_do_mlock() normal function in mm/mlock.c c) exports can_do_mlock() to not break compilation d) adds sched.h inclusions back to files that were getting it indirectly. e) adds less bloated headers to some files (asm/signal.h, jiffies.h) that were getting them indirectly Net result is: a) mm.h users would get less code to open, read, preprocess, parse, ... if they don't need sched.h b) sched.h stops being dependency for significant number of files: on x86_64 allmodconfig touching sched.h results in recompile of 4083 files, after patch it's only 3744 (-8.3%). Cross-compile tested on all arm defconfigs, all mips defconfigs, all powerpc defconfigs, alpha alpha-up arm i386 i386-up i386-defconfig i386-allnoconfig ia64 ia64-up m68k mips parisc parisc-up powerpc powerpc-up s390 s390-up sparc sparc-up sparc64 sparc64-up um-x86_64 x86_64 x86_64-up x86_64-defconfig x86_64-allnoconfig as well as my two usual configs. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-19IB/core: Free umem when mm is already goneEli Cohen
Free umem when task's mm is already destroyed by the time ib_umem_release gets called. Found by Dotan Barak at Mellanox. Signed-off-by: Eli Cohen <eli@mellanox.co.il> Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-05-08IB: Put rlimit accounting struct in struct ib_umemRoland Dreier
When memory pinned with ib_umem_get() is released, ib_umem_release() needs to subtract the amount of memory being unpinned from mm->locked_vm. However, ib_umem_release() may be called with mm->mmap_sem already held for writing if the memory is being released as part of an munmap() call, so it is sometimes necessary to defer this accounting into a workqueue. However, the work struct used to defer this accounting is dynamically allocated before it is queued, so there is the possibility of failing that allocation. If the allocation fails, then ib_umem_release has no choice except to bail out and leave the process with a permanently elevated locked_vm. Fix this by allocating the structure to defer accounting as part of the original struct ib_umem, so there's no possibility of failing a later allocation if creating the struct ib_umem and pinning memory succeeds. Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-05-08IB/uverbs: Export ib_umem_get()/ib_umem_release() to modulesRoland Dreier
Export ib_umem_get()/ib_umem_release() and put low-level drivers in control of when to call ib_umem_get() to pin and DMA map userspace, rather than always calling it in ib_uverbs_reg_mr() before calling the low-level driver's reg_user_mr method. Also move these functions to be in the ib_core module instead of ib_uverbs, so that driver modules using them do not depend on ib_uverbs. This has a number of advantages: - It is better design from the standpoint of making generic code a library that can be used or overridden by device-specific code as the details of specific devices dictate. - Drivers that do not need to pin userspace memory regions do not need to take the performance hit of calling ib_mem_get(). For example, although I have not tried to implement it in this patch, the ipath driver should be able to avoid pinning memory and just use copy_{to,from}_user() to access userspace memory regions. - Buffers that need special mapping treatment can be identified by the low-level driver. For example, it may be possible to solve some Altix-specific memory ordering issues with mthca CQs in userspace by mapping CQ buffers with extra flags. - Drivers that need to pin and DMA map userspace memory for things other than memory regions can use ib_umem_get() directly, instead of hacks using extra parameters to their reg_phys_mr method. For example, the mlx4 driver that is pending being merged needs to pin and DMA map QP and CQ buffers, but it does not need to create a memory key for these buffers. So the cleanest solution is for mlx4 to call ib_umem_get() in the create_qp and create_cq methods. Signed-off-by: Roland Dreier <rolandd@cisco.com>