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charset="UTF-8" X-Stat-Signature: xptsw5sm3amzmueoixgtxuz16gcecbc4 X-Rspamd-Queue-Id: 8A0801C0003 X-Rspamd-Server: rspam01 X-Rspam-User: X-HE-Tag: 1783554541-588025 X-HE-Meta: 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 6MwR1D0L cp28sKrYWNJhsszqSfNaHWq0g9qunWE7p1f62N5vvO2CAfom2haaNX2jn9U7xQcDce0Y5wzoveEfnORrYz2IPEwVQ7o1COMsSxakIki97WHmOXpAoGkDIAuUTuTebvP51vdxrKpMI2jU0eZlw5XmvDNLbvobT36uo2JTTA/t2MIBMYtRe8JF8TvRHGBWh+hoIAU5bXLbLEwkpIA9WS9YeTSURz2O+3Mjta/z1y2sfZDCYtwHbqYayujVHlebfbsRAM56dLo0ySDkf0cW0BuJoyB7HWLZTvWNIxyLApFM0D1Y0BXhEuY84afJT6GuoBk5N1+CGGpkLMCUvZGJQSex8J0ajYpbxFkS8OYAJoo79CIylxftqV5eZL7c+PyWDFWo/Ipz8sxgBX2gbcuaVYakkc0fOyvJYwgWdHu6sPmNoR7+X8k6pgpGA/FZOaNtdJkfNoh6VuN5aD/vlPR0EygqGmsDmvw324VjD81veCecfPErTXmqH+/9LUeFJ57wYN0nymbPahh2ReRzOxh4B0ugBrXWxIZ57VgUeo9ksZBptq43hj+4qD3TbWlqIiSvQS+OrQV2z7/iO4RWrxtm1oZfaqhaUHPvSP0XFu4OV Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Add new DMA APIs that allow preserving/restoring DMA allocations across live update. Signed-off-by: Samiullah Khawaja --- include/linux/dma-mapping.h | 50 +++++++++++++++++++++++++++++++++++++ kernel/dma/mapping.c | 49 ++++++++++++++++++++++++++++++++++++ 2 files changed, 99 insertions(+) diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h index db8ab24a54f4..3756fc15467b 100644 --- a/include/linux/dma-mapping.h +++ b/include/linux/dma-mapping.h @@ -210,6 +210,15 @@ void *dma_vmap_noncontiguous(struct device *dev, size_t size, void dma_vunmap_noncontiguous(struct device *dev, void *vaddr); int dma_mmap_noncontiguous(struct device *dev, struct vm_area_struct *vma, size_t size, struct sg_table *sgt); +#ifdef CONFIG_DMA_LIVEUPDATE +int dma_preserve_allocation_attrs(struct device *dev, void *cpu_addr, + size_t size, dma_addr_t dma_handle, + unsigned long attrs, u64 *state); +void dma_unpreserve_allocation(struct device *dev, u64 state); +void *dma_restore_allocation_attrs(struct device *dev, size_t size, + dma_addr_t *dma_handle, gfp_t gfp, + unsigned long attrs, u64 state); +#endif #else /* CONFIG_HAS_DMA */ static inline dma_addr_t dma_map_page_attrs(struct device *dev, struct page *page, size_t offset, size_t size, @@ -496,6 +505,26 @@ static inline bool dma_need_unmap(struct device *dev) } #endif /* !CONFIG_HAS_DMA || !CONFIG_DMA_NEED_SYNC */ +#if !defined(CONFIG_DMA_LIVEUPDATE) || !defined(CONFIG_HAS_DMA) +static inline int dma_preserve_allocation_attrs(struct device *dev, void *cpu_addr, + size_t size, dma_addr_t dma_handle, + unsigned long attrs, u64 *state) +{ + return -EOPNOTSUPP; +} + +static inline void dma_unpreserve_allocation(struct device *dev, u64 state) +{ +} + +static inline void *dma_restore_allocation_attrs(struct device *dev, size_t size, + dma_addr_t *dma_handle, gfp_t gfp, + unsigned long attrs, u64 state) +{ + return NULL; +} +#endif + struct page *dma_alloc_pages(struct device *dev, size_t size, dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp); void dma_free_pages(struct device *dev, size_t size, struct page *page, @@ -618,6 +647,27 @@ static inline void *dma_alloc_coherent(struct device *dev, size_t size, (gfp & __GFP_NOWARN) ? DMA_ATTR_NO_WARN : 0); } +static inline int dma_preserve_coherent_allocation(struct device *dev, void *cpu_addr, + size_t size, dma_addr_t dma_handle, u64 *state) +{ + return dma_preserve_allocation_attrs(dev, cpu_addr, size, + dma_handle, 0, state); +} + +static inline void dma_unpreserve_coherent_allocation(struct device *dev, u64 state) +{ + dma_unpreserve_allocation(dev, state); +} + +static inline void *dma_restore_coherent_allocation(struct device *dev, size_t size, + dma_addr_t *dma_handle, + gfp_t gfp, u64 state) +{ + return dma_restore_allocation_attrs(dev, size, dma_handle, gfp, + (gfp & __GFP_NOWARN) ? DMA_ATTR_NO_WARN : 0, + state); +} + static inline void dma_free_coherent(struct device *dev, size_t size, void *cpu_addr, dma_addr_t dma_handle) { diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c index 23ed8eb9233e..3b07bf30722c 100644 --- a/kernel/dma/mapping.c +++ b/kernel/dma/mapping.c @@ -12,6 +12,8 @@ #include #include #include +#include +#include #include #include #include @@ -628,6 +630,53 @@ u64 dma_get_required_mask(struct device *dev) } EXPORT_SYMBOL_GPL(dma_get_required_mask); +#ifdef CONFIG_DMA_LIVEUPDATE +int dma_preserve_allocation_attrs(struct device *dev, void *cpu_addr, + size_t size, dma_addr_t dma_handle, + unsigned long attrs, u64 *state) +{ + const struct dma_map_ops *ops = get_dma_ops(dev); + + if (dma_is_from_dev_coherent(dev, cpu_addr)) + return -EOPNOTSUPP; + + if (dma_alloc_direct(dev, ops)) + return dma_direct_preserve_allocation(dev, cpu_addr, size, + dma_handle, attrs, + state); + + return -EOPNOTSUPP; +} +EXPORT_SYMBOL(dma_preserve_allocation_attrs); + +void dma_unpreserve_allocation(struct device *dev, u64 state) +{ + const struct dma_map_ops *ops = get_dma_ops(dev); + + if (dma_alloc_direct(dev, ops)) + dma_direct_unpreserve_allocation(dev, state); +} +EXPORT_SYMBOL(dma_unpreserve_allocation); + +void *dma_restore_allocation_attrs(struct device *dev, size_t size, + dma_addr_t *dma_handle, gfp_t gfp, + unsigned long attrs, u64 state) +{ + const struct dma_map_ops *ops = get_dma_ops(dev); + void *cpu_addr = NULL; + + WARN_ON_ONCE(!dev->coherent_dma_mask); + + if (dma_alloc_direct(dev, ops)) + cpu_addr = dma_direct_restore_allocation(dev, size, dma_handle, + gfp, attrs, state); + + debug_dma_alloc_coherent(dev, size, *dma_handle, cpu_addr, attrs); + return cpu_addr; +} +EXPORT_SYMBOL(dma_restore_allocation_attrs); +#endif + void *dma_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle, gfp_t flag, unsigned long attrs) { -- 2.55.0.795.g602f6c329a-goog