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| author | Damien Le Moal <dlemoal@kernel.org> | 2024-10-12 20:32:42 +0900 |
|---|---|---|
| committer | Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> | 2024-10-12 17:25:54 +0530 |
| commit | 2314c6ffe8113ac3c22c8112fa9623e30eec6c4a (patch) | |
| tree | aa7d7d7f26dd4b31407d58e34810c458427273bf | |
| parent | ca3c342fb3c76eee739a1cfc4ff59841722ebee7 (diff) | |
| download | lwn-2314c6ffe8113ac3c22c8112fa9623e30eec6c4a.tar.gz lwn-2314c6ffe8113ac3c22c8112fa9623e30eec6c4a.zip | |
PCI: endpoint: Improve pci_epc_mem_alloc_addr()
There is no point in attempting to allocate memory from an endpoint
controller memory window if the requested size is larger than the memory
window size. Add a check to skip bitmap_find_free_region() calls for
such case. This check can be done without the mem->lock mutex held as
memory window sizes are constant and never modified at runtime.
Also change the final return to return NULL to simplify the code.
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Niklas Cassel <cassel@kernel.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20241012113246.95634-3-dlemoal@kernel.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
| -rw-r--r-- | drivers/pci/endpoint/pci-epc-mem.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/drivers/pci/endpoint/pci-epc-mem.c b/drivers/pci/endpoint/pci-epc-mem.c index a9c028f58da1..218a60e945db 100644 --- a/drivers/pci/endpoint/pci-epc-mem.c +++ b/drivers/pci/endpoint/pci-epc-mem.c @@ -178,7 +178,7 @@ EXPORT_SYMBOL_GPL(pci_epc_mem_exit); void __iomem *pci_epc_mem_alloc_addr(struct pci_epc *epc, phys_addr_t *phys_addr, size_t size) { - void __iomem *virt_addr = NULL; + void __iomem *virt_addr; struct pci_epc_mem *mem; unsigned int page_shift; size_t align_size; @@ -188,10 +188,13 @@ void __iomem *pci_epc_mem_alloc_addr(struct pci_epc *epc, for (i = 0; i < epc->num_windows; i++) { mem = epc->windows[i]; - mutex_lock(&mem->lock); + if (size > mem->window.size) + continue; + align_size = ALIGN(size, mem->window.page_size); order = pci_epc_mem_get_order(mem, align_size); + mutex_lock(&mem->lock); pageno = bitmap_find_free_region(mem->bitmap, mem->pages, order); if (pageno >= 0) { @@ -211,7 +214,7 @@ void __iomem *pci_epc_mem_alloc_addr(struct pci_epc *epc, mutex_unlock(&mem->lock); } - return virt_addr; + return NULL; } EXPORT_SYMBOL_GPL(pci_epc_mem_alloc_addr); |